AviationFacilities Heating

CORAYVAC® Warms U.S.A.F Thunderbirds, Niagara Falls Air Reserve Base CORAYVAC® Warms Desert Storm Troops, Niagara Falls Air Reserve Base CORAYVAC® Warms Refueling Tanker back from Desert Storm, Pittsburgh ANG CORAYVAC® Warms Air Frame/Jet Engine Modification & Repair Hangar, TravisAFB CORAYVAC® Warms U.S.A.F. Corrosion Control Hangar, Mather AFB CORAYVAC® Warms Delta Air Lines Hangar, Salt Lake City, Utah CORAYVAC® Warms Northwest Airlines Hangar, Memphis/Shelby County Airport CORAYVAC® Warms Baggage Train Facility, Memphis/Shelby County Airport CORAYVAC® Warms Weyerhauser Corporate Hangar, Seattle, WA. CORAYVAC® Warms MBW Helicopter Facility, Ft. Erie, Ontario, and Philadelphia, PA. CORAYVAC® Warms Airport Ticketing Area Terminal “A”, Philadelphia, PA. ECONOVAC® Warms American Airlines Hangar, LaGuardia Airport CORAYVAC® Warms Federal Express Package Handlers, Salt Lake City, Utah ECONOVAC® Assists in Snow Melting on Parking Ramp, Denver, CO. CORAYVAC® Warms Airport Runway Maintenance Vehicle Garage, Chicago O’Hare CORAYVAC® Warms Ground Support Vehicle Service Building, Pittsburgh Airport CORAYVAC® Warms Airport Crash/Sire/Rescue Station, Seattle, WA. VANTAGE® II Warms Vestibules above Decorative Grille III. Basics of Infrared Heating What is Infrared? Utility of Infrared Methodology of Radiant Heating Appliances IV. Types of Radiant Heating Equipment ASHRAE Defined Types Market Defined Types AviationFacilities Heating V. Concept of CORAYVAC ® Concept The CORAYVAC ® System Safety Zero Regulators Fuel Savings with CORAYVAC ® Selecting the Burner Flow Loading Radiant Branch Flow Tailpipe Flow Pump Capacity Heating Exchange Surface Radiant Pipe Tailpipe Air Supply System VI. Heat Loss and Annual Fuel Use Calculations Building Heat Loss and Sizing Systems Radiant Adjustment to Heat Loss Radiant Height Adjustment Factor Building Survey(F8149111) Heat Loss Calculation Worksheet (F814912) Fuel Usage Comparison Worksheet (F814913) Fuel Utilization Formula Deviation U Factors Calculation Illustrative Example VII. CORAYVAC ® B Series Classic Specifications CORAYVAC ® B Classic 15 Year Warranty Federal Court Ruling on Proprietary Specifications VIII. Appendix Size and Weights of Various Aircraft BOCA National Code, Ventilation ASHRAE Standard 62-1989 Ventilation for Acceptable Indoor Air Quality Uniform Mechanical Code, Condensate Disposal Table, Building Volume Vs % Air Change Per Hour Air National Guard Outside Air Ventilation Standards Excerpts from U.S.A.F. Manual 88-15 Chapter 1 Policy for Criteria & Design if Air Force Facilities Hazardous Areas AviationFacilities Heating Gas Supply and Distribution U.S.A.F. Message 148 Dual Spectrum Fire Detection Systems, Memo 9/5/86 Degree Day and Design Temperature for U.S. Cities IX. Users List U.S. Facility Installation List, by State X. Users List U.S. Military Installation List, by State AviationFacilities Heating All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating General Advantages of CORAYVAC ® Safety • No exposed flame • 100% safety shut-off • Zero pressure regulator • Fully vented • Outside combustion air option • Low clearances to combustibles Comfort • Reduced heat stratification; more even heating throughout the building, including floors and equipment • No blowing hot air spreading dirt, grit and dust throughout the hangar • Small pumps result in low level operating noise • Rapid heat recovery from opening of doors, etc. • Warm floors means warm feet • Warm tools means warm hands Operation • Fully prewired control panel box standard with each system • Panel box compatible with all energy management systems • Zone control by standard thermostat, sensor, night setback, 7 day timer, etc.; virtually all types of controls are compatible • Direct spark to burner ignition • Minimal maintenance; filter change on each burner every one to three years Miscellaneous Hangar Advantages • Approved with dual spectrum fire detection systems • A.G.A. certified for use in aircraft hangars • Deluge proof; in case of deluge discharge, change filters and system will operate normally • Meets codes for aircraft hangar use including: military, B.O.C.A., A.G.A., and N.F.P.A. • No valuable floor space required; system is out of the way in the roof structure • Most easily serviced with man lift or cherry picker; no catwalks required • Substantial fuel savings • Aid in de-icing of planes and rapid drying of water from hangar floor CORAYVAC ® vs, Other Heating Systems Underfloor Radiant • CORAYVAC ® generally has lower initial cost • CORAYVAC ® generally has lower operating cost • CORAYVAC ® is easier to service; underground service can be difficult • CORAYVAC ® has night set-back ability, underground does not due to extensive heat recovery time Boiler Hot Water or Steam • CORAYVAC® generally has lower initial cost • CORAYVAC® generally has lower operating cost • CORAYVAC® does not create problems with air stratification • CORAYVAC® has rapid recovery time unlike the extensive recovery time of boiler systems • CORAYVAC® requires no floor space - boiler system very often require a room of their own Warm Air, Gas Fired Heaters • CORAYVAC ® generally has lower operational cost • CORAYVAC ® does not create air stratification • CORAYVAC ® has tremendous ability to heat floors as well as objects • CORAYVAC ® takes up no floor space - large warm air floor mounted units can take up a considerate amount of space • CORAYVAC ® has quicker hear recovery High Intensity Infrared • CORAYVAC ® is a completely unexposed system, unlike high intensity which has exposed flames reaching temperatures of 1800°F • CORAYVAC ® flame is completely vented, high intensity is unvented and therefore cannot compensate for products of combustion which may cause corrosive con densation problems • CORAYVAC ® has lower clearances to combustibles compared to high intensity • CORAYVAC® , due to lower temperature, does not interfere with fire temperature systems • CORAYVAC ® has more even heat, high intensity has drastic hot and cold spots • CORAYVAC ® generally has lower maintenance costs CORAYVAC ® vs. Other Low Intensity Systems • CORAYVAC ® is more efficient than other low intensity systems • CORAYVAC ® has optimal reflector design to properly direct heat • CORAYVAC® burner in series design in unmatched in the industry for even radiant patterns • CORAYVAC ® is able to handle condensate • CORAYVAC® has lower exhaust temperature relative to other low intensity systems • Burner in series design allows system to perform if one burner fails; end burner only systems shut down completely if end burner fails • CORAYVAC ® has a full 15 year warranty • CORAYVAC ® has heavy duty long lasting construction compared to other low intensity systems • CORAYVAC® has proven successful in hangar heating and other airport applications for over 30 years All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. CORAYVAC® Helps Reduce Energy Bills and Improve Comfort CORAYVAC® gas-fired, low-intensity, infrared heating systems help provide custom comfort, while facilitating reduced energy consumption up to 50% and more! CORAYVAC® is a continuous burners-in-series vacuum-operated system that can be designed to condense. This efficient operating mode, combined with the principles of infrared energy, can result in considerable energy savings and comfort, while helping to lower your building’s carbon footprint and environmental impact. With the innovation of CORAYVAC®, Roberts-Gordon pioneered energy efficient low-intensity, infrared heating. Today, CORAYVAC® continues to innovate green products by offering a fully modulating infrared heating system. LESS HEAT STRATIFICATION CORAYVAC® does not blow high temperature heated air that ends up rising to the ceiling. In fact, CORAYVAC® does not heat air. CORAYVAC® reflects and directs infrared energy toward the floor. The infrared energy is in the form of electromagnetic waves that can be directed and reflected like light. These waves travel through the air (not heating it) toward the floor until they strike solid objects. The objects are heated when they absorb the infrared energy. Floors, people and equipment below CORAYVAC® absorb and store heat, then re-radiate heat and warm the air by convection as air passes across the warm objects. Compared to other tra- ditional heating systems, CORAYVAC® uses less energy to heat the area at occupant level. In addition, since there is no need for ceiling fans to push heat to the floor, electrical usage can be reduced. REDUCED BUILDING HEAT LOSS Because CORAYVAC® does not introduce high temperature air into the heated space, it generates less heat stratification. Air temperatures at the ceiling are lower than with other heating systems. Lower ceiling temperatures result in reduced heat loss through the roof and lowered building heat loss. Lowered building heat loss means less heat is needed to heat the same space. FLOORS BECOME HEAT RESERVOIRS The sun does not heat the earth’s atmosphere directly; rather its infrared rays heat the earth, people and objects. CORAYVAC® uses less fuel than other heating systems because it heats a building and its occupants similar to how the sun heats the earth. With CORAYVAC®, floors and objects become massive secondary heat exchangers. These objects act as heat reservoirs, storing heat, then releasing it into the space by re-radiation and convection to raise space temperature at occupant level. FREE ENERGY RECOVERY In commercial and industrial buildings, rapid air changes and heat loss commonly occur when large doors are opened. As a result, valuable heated air escapes outdoors, wasting money. With air heating, more time and money is required for heat recovery because all the energy burned is used only to heat air, when the heated air is lost, no energy remains in the space. With CORAYVAC®, energy stored in floors and objects is re-used for faster energy recovery in the space, without burning more fuel. GREATER COMFORT AT LOWER TEMPERATURES To obtain fuel savings of up to 50% over conventional heating systems, it is essential to design an infrared system for maximum distribution and comfort. When designing systems for comfort, or reaching the operative temperature (T0), designers need to maximize the mean radiant temperature (MRT) and depress the air temperature (Tair). For example, to reach a perceived comfort of 65° F (18° C), with infrared, the air temperature can be lowered to 55° F (12° C). This helps reduce energy costs! Due to elevated mean radiant space temperature, building occupants feel the same amount of warmth when thermostats are set 5° to 10° F (-15° to -12° C) lower with CORAYVAC® than with other heating systems. Lower thermostat setpoint translates into additional energy savings. CLEAN, QUIET, DRAFT-FREE HEAT Since CORAYVAC® quietly warms objects without drafts or blowing air, heated areas are cleaner and quieter. HIGH EFFICIENCY CONDENSING SYSTEM CORAYVAC® is unique from other infrared heaters because it can be designed as a condensing system. Lowering exhaust temperatures puts more heat in the space and less wasted through the exhaust. This results in additional efficiency and fuel savings. ENHANCED FUEL SAVINGS WITH MODULATION CORAYVAC® modulating and building management controls package, called ULTRAVAC™, allow building owners to graduate to higher levels of comfort and energy efficiency. PC based centralized building management control and connectivity is provided in an easy-to-use Windows-based software package. These controls, coupled with proper burner modulation (continuous adjustment of fuel and combustion air), compound the energy saving benefits of CORAYVAC®. An economical CORAYVAC® modulating controls package is also available. CORAYVAC® helps provide a field-proven solution for today’s green industrial and a variety of commercial buildings. UNIFORM COMFORT Continuous burners-in-series design with custom layout provides even heating and uniform comfort. CORAYVAC® systems are custom-engineered and designed to match the specific building plan and space requirements. CORAYVAC® spreads a gentle blanket of low-intensity, infrared energy that directly warms people, floors and objects in a building. By more effectively delivering heat to the occupied area (floor level), CORAYVAC® offers many benefits that can result in improved conditions and greater fuel savings. Proper design, installation, use and maintenance is necessary for optimum performance. This document is intended to assist licensed professionals in the exercise of their professional judgment. TUBING The CORAYVAC® system utilizes 4” O.D. (100 mm), 16-gauge tubing. The heat created by the burners is drawn through the tubes, which radiate the warm, gentle, infrared energy. Hot-rolled steel, aluminized steel or double porcelain coated steel tubing are available. Double porcelain coated steel is a cured por- celain coating on the inside and outside surface of the tube, which helps to maximize longevity and minimize corrosion of condensing systems. VACUUM PUMPS A vacuum pump draws the heat throughout the entire system. It exhausts products of combustion to the outdoors at temperatures typically below 150° F (66° C). 1/3-hp, 3/4-hp or 2-hp are available for various system sizes and layouts. Up to twelve heaters can be common vented with one vacuum pump. Design flexibility allows side wall venting, even in large buildings. BURNERS-IN-SERIES DESIGN Located from 10 ft. - 70 ft. (3 m to 21.3 m) apart, CORAYVAC® burners constantly regulate the air-to-gas mixture to achieve the optimum ratio for clean, efficient combustion. Models are available with inputs of 20,000 through 120,000 Btu/h. Features include three-try direct spark ignition, pre-purge, filtered combustion air and cast-iron burner head. REFLECTORS ROBERTS GORDON® deep-dish, continuous aluminum reflectors are shaped to help maximize reflection of the energy emitted by the infrared tube and beamed toward the floor where needed. End caps and continuous reflectors help keep tube convective heat loss to a minimum and help ensure heat exchangers maintain heat. CORAYVAC® High Efficiency, Condensing Infrared System Features Uniform Heat with CORAYVAC® In-Series Burners COMBUSTION CHAMBERS Four types of combustion chambers are available for the CORAYVAC® system: cast-iron, hot rolled steel, aluminized steel and double porcelain coated steel. The heavy-duty, cast-iron combustion chamber can be fitted with schedule 40 pipe throughout the system. Double porcelain coated steel is a cured porcelain coating on the inside and outside surface of the chamber, helping to maximize longevity and minimize corrosion of condensing systems. COUPLINGS Heat exchanger tubing is connected together with couplings. Roberts-Gordon offers stainless steel couplings, lined couplings and damper couplings. MODULATING BURNER CONTROLS Designed for the energy conscious, ULTRAVAC™ Modulating Controls are Roberts-Gordon’s energy saving control package. See the ULTRAVAC® pages of this brochure for details. Economical CORAYVAC® modulating controls package and basic controls are also available. See the accessories page of this brochure for details. Condensing System - Designed to Condense for Optimum Fuel Saving Efficiency. Machine Shops Distribution Centers Auto Dealerships Vehicle Service Shops Bus Garages Fire Stations Farm Buildings Stores Package/Parcel Hubs Swimming Pools Zoo Sports Facilities Vehicle Repair Shops Warehouses / Distribution Centers CORAYVAC® can heat an as well as provide sepa control for th Metal Buildings Loading Docks Auto Body Shops Truck Terminals Parking Ramps Sports Facilities Workshops Showrooms Restaurants Hockey Rinks Animal Confinement Buildings Manufacturing Plants Equipment and Vehicle Storage Garages Aircraft Hangars entire building evenly, rate zone temperature he building. BURNER MODULATION FOR REDUCED FUEL AND ELECTRICAL USAGE CORAYVAC® burners are equipped with a zero pressure regulator, which alters the amount of vacuum applied to the burner, thereby varying burner input. Altering vacuum also varies combustion air supplied to the burner. Since the fuel and air are changed proportionately, proper, efficient combustion can be achieved throughout the modulation range. ULTRAVAC™ Controls utilize an energy saving programmable variable frequency drive (VFD) at the vacuum pump resulting in drastic electrical savings compared to a mechanical damper at the pump. The inefficient mechanical damper method of varying system vacuum, increases electrical consumption as the pressure drop across the damper increases. Featuring fuel to air linkage technology, ULTRAVAC™ is a micro-processor based controls package designed to modulate CORAYVAC® systems. The controls provide proper modulation by varying system vacuum and adjusting gas and combustion air according to the indoor/outdoor temperatures and building heat loss. Matching system input to the building heat loss helps reduce heater cycling and temperature set point overshoot. ULTRAVAC™ helps increase the system efficiency and helps maximize fuel savings. The controls fully modulate burners between 60% and 100% of the burner’s maximum rated input. With the combined strengths of CORAYVAC® and ULTRAVAC™, buildings can be designed for comfort without the worry of high heating bills. Obtain Even Greater Energy Savings with ULTRAVAC™ Controls! ELECTRICAL SAVINGS* (CORAYVAC® with ULTRAVAC™ Controls vs. others) Seasonal Electricity Consumption *Estimated savings, results may vary. 86% Savings Over Direct-Fired Make-Up Air 93% Savings Over Air Turnover 73% Savings Over Unit Heaters URV URV URV FUEL SAVINGS* (CORAYVAC® with ULTRAVAC™ Controls vs. others) 45% Savings Over Direct-Fired Make-Up Air 30% Savings Over Air Turnover 41% Savings Over Unit Heaters URV URV URV Seasonal Fuel Consumption *Estimated savings, results may vary. ELECTRICAL SAVINGS* (CORAYVAC® with ULTRAVAC™ Controls vs. others) Seasonal Electricity Consumption *Estimated savings, results may vary. 86% Savings Over Direct-Fired Make-Up Air 93% Savings Over Air Turnover 73% Savings Over Unit Heaters URV URV URV FUEL SAVINGS* (CORAYVAC® with ULTRAVAC™ Controls vs. others) 45% Savings Over Direct-Fired Make-Up Air 30% Savings Over Air Turnover 41% Savings Over Unit Heaters URV URV URV Seasonal Fuel Consumption *Estimated savings, results may vary. UltraVac™ SECURITY AND TAMPER PROOF CONTROL By networking controllers together, ULTRAVAC™ provides centralized control, helping to ensure security and tamper-proof management, as well as efficient operation of the CORAYVAC® heating system. BACnet® is a registered trademark of ASHRAE. Roberts-Gordon LLC is not sponsored by or affiliated with ASHRAE. CONNECTIVITY AND INTERFACE CONTROLS Buildings today demand all sorts of control options based on the user’s preference. ULTRAVAC™ controls offer a host of communication options for seamless integration with your controls network to best serve your individual needs: ® BACnet®: Interface ULTRAVAC™ with other building management control platforms with our BACnet® option. TCP/IP (LAN): Connect to ULTRAVAC™ via your local area network of computers. Load ULTRAVAC™ software onto any computer on the network and control and view your heating system from your computer. MODEM: Dial into ULTRAVAC™ from anywhere in the world via modem. Supplied as standard on all central controllers! RS-485: Hard wire ULTRAVAC™ directly to your computer. CENTRALIZED BUILDING MANAGEMENT ULTRAVAC™ provides networked and centralized building management from the convenience of your PC! In addition to significant energy savings, ULTRAVAC™ controls are easy to use. Windows-based software provides simple point and click control and programming that is intuitive and easy to understand. The software provides a graphical representation feature to show the entire building status at a glance. The controls continuously monitor system status and settings, allowing you to view indoor and outdoor temperatures or alter system settings or programming at any time. SIDE REFLECTOR Optional side reflector extensions direct heat towards the floor and center of the building when CORAYVAC® is mounted near a wall. DECO GRILLE Optional decorative two-foot grille for use with drop ceilings. CORAYVAC® High-Efficiency, Condensing Infrared Heating System Accessories UNIVERSAL SHIELD Universal shields are aluminum reflectors whose angle and height can be adjusted to direct heat to or away from a desired area. Universal shields are available with or without holes. CONTROL OPTIONS In addition to ULTRAVAC™, CORAYVAC® systems can also be controlled by CORAYVAC® modulating controls, a System Control or a relay. The System Control is an electronic control panel capable of controlling up to four zones of burners and two pumps. PROTECTIVE GRILLE Protective grilles conveniently attach to reflectors to cover the radiant tubing. This helps prevent items from coming in contact with the radiant tubes. Printed in U.S.A. CRVBNA 5M 0110 Orig. © 2010 Roberts-Gordon LLC All rights reserved. No part of this work covered by the copyrights herein may be reproduced or copied in any form or by any means – graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems – without written permission of Roberts-Gordon LLC. Roberts-Gordon LLC 1250 William Street P.O. Box 44 Buffalo, NY 14240-0044 USA Telephone: +1.716.852.4400 Fax: +1.716.852.0854 Toll Free: 800.828.7450 www.rg-inc.com www.corayvac.com www.radiantheaters.com www.greenhouse-heater.com Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. n Variety of design options from custom engineered system n Fuel savings and enhanced user comfort provided by burners-in-series design n Excellent efficiency and ideal combustion from zero regulator incorporated in state of the art burner design n Maximizes usable space with low clearances to combustibles n Extra safety feature with zero regulator design n Reduced building penetrations as a result of multiple burners per pump n Environmentally friendly - meets stringent emission standards CoRayVac® Quality in Any LanguageTM Low-Intensity Continuous Infrared Heating System ���������� �������������� ������������������� � �������������� Installation Code and Annual Inspections: All installations and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon recommends that a qualified contractor annually inspect your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. This product is not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgement. © 2007 Roberts-Gordon All rights reserved. No part of this work covered by the copyrights herein may be reproduced or copied in any form or by any means – graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems – without written permission of Roberts-Gordon. Printed in U.S.A. CRVSNA 5M 0607 Rev E CORAYVAC® Model B-2 B-4 B-6 B-8 B-9 B-10 B-12A B-12 Burners in a Branch* max. 6 4 4 4 2 4 4 4 Radiant Tube Length Between Burners [ft] min. 10 12.5 20 20 25 30 35 35 Recommended 15 20 25 30 30 40 50 50 max. 20 25 35 45 50 60 70 70 Input (Btu/h) x (1000) 20 40 60 80 90 100 110 120 Inlet Pressure [in wc] NG min. 4.5 LPG Propane min. 10.5 NG & LPG Propane max. 14 Gas Connection NPT ½" Fuel NG or LPG Propane; B2 and B12A - NG Only; B12 - LPG Only Electrical Supply** 120 V, 60 Hz, 0.3 A (Connection Cord with Three-Prong Molded Plug) Burner Head Cast Iron Combustion Chamber 16 Gauge Hot Rolled, Heat-Treated Aluminized, or Cast Iron Heat Exchanger Tubing Radiant Tailpipe 4" dia, 16 Gauge Hot Rolled, Aluminized, Heat-Treated Aluminized, or 4" Schedule 40 Pipe 4" or 6" dia, 16 Gauge Aluminized, Heat-Treated Aluminized Exhaust Flue dia 4" or 6" Reflector and End Caps .024 Aluminum [Optional - .024 Stainless Steel Type 304] Control System Fully Automatic, Three-Try, 100% Shut-Off, Direct Spark Electronic Ignition Control Approved As Indoor (Vented) Certification ANSI Z83.20/CSA 2.34, 2.17 Burner Weight [lb] 19 Warranty Three-Year Limited (Refer to Installation, Operation and Service Manual for Details) ***Clearances B, C and D can be reduced by 50% for locations 25 ft (7 m) or more downstream of the burner. For other mounting options and associated clearances, complete instal- lation, operation and service criteria, please see the current issue of the Installation, Operation and Service Manual. Clearances to Combustibles ***[in] Model B-2 B-4 B-6 B-8 B-9 B-10 B-12A B-12 Horizontal A 4 4 4 4 4 4 4 4 B 20 20 20 20 36 36 36 36 C 48 48 48 48 60 60 60 60 D 20 20 20 20 36 36 36 36 Roberts-Gordon, LLC 1250 William Street P.O. Box 44 Buffalo, NY 14240-0044 USA Telephone: 716.852.4400 Fax: 716.852.0854 Toll Free: 800.828.7450 www.rg-inc.com European Office: Roberts-Gordon Europe Limited Telephone: +44(0)121 506 7700 Fax: +44(0)121 506 7701 *Pump type, system layout and environmental conditions may reduce maximum allowable burners in a branch. Refer to the CORAYVAC® Design Manual for complete design requirements or contact your ROBERTS GORDON® North American independent distributor for further assistance. **Refer to Pump Spec Sheet for complete system electrical requirements. � � � � ��� ������� ��� ��������� ������ ������� ������� ������� �� ������� ������ ������� ������ ������ ������ ������� ������� ������� ������ ������� ����� ������� All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating Case Histories Radiant Heating System Mounted at 65 Feet Proves Itself During Record Cold Spell Georgia isn’t noted for winter snowfalls and extremely cold temperatures, but the week of March 7, 1993 was an exception. Hurricane force winds coupled with record cold temperatures and blowing snow made weather conditions treacherous up and down the state. However, at Robins Air Force Base near Macon, Georgia, the innovative hangar heating system kept workers warm and comfortable even under these adverse weather conditions. Three new 74 foot high hangars were built at “Robins” during the last year. A contingent con- sisting of a base civil engineer, several consulting engineers and i visited the hangars a few days after the storm. It was miserable outside. A cold wet rain soaked us as we ran from our van to the hangars. But when we stepped inside, it was like walking into Hawaiian sunshine. The hangars were 372 feet wide. One was 200 feet long and the other, 400 feet long. A CoRayVac ® gas-fired, low intensity infrared heating system was mounted at 65 feet above the finished floor. As we walked in the hangar, we could feel the radiant heat. There was no noise or drafty blowing air from the heating system, just silent, infrared heat warming all the object in the building. CORAYVAC ® heating systems are becoming more popular for economically heating high build- ings. The infrared rays from their emitter tubes are directly downward. When they strike and object, the object gets warm and releases it’s heat to the air. Air temperatures in infrared heated buildings are usually lower than when other types of heat are used. The phenomena is similar to standing outside on a spring day. The air might be 60 degrees, but you feel the warmth of the sun so you feel comfortable. CORAYVAC ® has another uniquely distinct feature. Because it is composed of smaller burn- ers firing in series, as compared to systems with one big burner at one end of a long tube, CORAYVAC ® provides uniform heat over the entire floor area of the hangar. The overall results of the heating high buildings with CoRayVac ® are numerous. CORAYVAC ® costs much less to operate than many other heating systems. It produces quiet draft free heat, provides heat recovery when large doors are closed, and in most cases is cheaper to install than boilers with radiators or steam unit heaters. Attached are pictures showing the heating CORAYVAC ® system mounted at 65 feet. It is above the overhead cranes. Pictures tell a lot, but they cannot describe the ideal comfort in these han- gars. Perhaps it was best described by the building supervisor who told us, “I’ve been working at this base for over 13 years and this is the most comfortable building I’ve worked in.” John G. Berkhoudt, V.P. National/International Accounts Roberts Gordon, Inc. CORAYVAC ® Mounted at 65 feet Robins Air Force Base “I’ve worked on this base for 13 years and this is the most comfortable building I have worked in.” - Hangar Superintendent, after a record cold spell Chosen for safety and economy of operation, a CORYAVAC ® system with eighteen cast iron “Classic” burners heats the NASA shuttle hangar at Edwards Air Force Base. Even in high bay buildings the fast warm up provides chill chasing warmth during cold nights and early mornings. “It’s so quiet you don’t know it’s there.” That’s what visitors to the Canadian Warmplane Heri- tage Museum, near the Hamilton, Ontario, Canada are saying about the gas fired, low intensity infrared system. Mounted high above the girders, enhanced with aluminium decorative grille, the system pro- vides safe, quiet, draft free comfort in this beautiful new aviation museum. CORAYVAC® Warms Desert Storm Troops Home to Niagara Falls “It’s great to be home.” was heard over and over again as our men and women of the 914th Tactical Aircraft Group, Niagara Falls, NY embrace relatives, friends and souses, or lifted sons and daughters to their shoulders. Grown men cried, a lot of them. And a high above, in silent witness hung our CORAYVAC ® system, providing warmth to this memorable occasion. This Air Force Reserve Hangar was originally heated with a combination system consisting of a “Hydronic Radiant Floor System” and hanging steam unit heaters. Users report that every year they had to purge the in floor heating system to start it up. The biggest problem was eliminating the air pockets in the tubes which were caused by oxygen diffusion. This can eventually lead to oxi- dation of boiler and tube components, resulting in premature systems failure. No matter how good the operating engineers were, they could never get rid of the oxygen diffusion problem. This fact, coupled with leaky tube problems, led to a decision to replace the floor heating system with CORAYVAC ® . Their steam unit heaters are still hanging, but since the CORAYVAC ® heating system was installed they have nor been turned on. The CORAYVAC ® provides all the heat needed. One of the most impressive changes was the fast heat recovery. Now, with CORAYVAC ® , the hangar and planes warm up fast when brought in from the cold outdoors. The Air Force Reservists tell the story about one night when it was 25°F outside, they brought in a cold KC130 aircraft covered with 3” of snow. In less than one hour the plane was de-iced, de- snowed and dry under the CORAYVAC ® . With in floor radiant heat the mechanics and technicians working on the floor complained that their backs were too warm while the front of their bodies were too cold. With the CORAYVAC ® heating system they wear less clothing and are always comfortable. CORAYVAC® Heats U.S. Thunderbirds During the Air Show several years ago the US Air Force Precision Thunderbird flying team housed their aircraft in the Niagara Falls Air Force Reserve Hangar. Notice the fresh air systems supplying each CORAYVAC ® burner with fresh outside air for combustion. In this case, 4” diameter Schedule 20 ABS plastic tube was used for the air supply line. The fresh air system is pressurized with a special CORAYVAC ® supplied blower. This way, if a leak does occur in the supply line, fresh air will be blown into the building instead of inside contaminated air being drawn into the burners. Outside air for combustion is commonly used in areas where the inside air might be contaminated with chemical or airborne particles. It may be well to remind the readers that CORAYVAC ® is not classified as explosion proof. If explosion proof equipment is required, CORAYVAC ® cannot be used. In this case you can see the lights are not explosion proof, which is a good indication that CORAYVAC ® can be used. CORYAVAC® Heats Refueling Tanker Back From Desert Storm The symbols painted on the side show how many successful missions the refuelling tanker made during the Desert Storm offensive. Men of the Pennsylvania Air national Guard are ex- tremely proud of their contribution to this war effort. They are also proud of their CORAYVAC® gas-fired, low intensity infrared heating system. Since this system was installed in 1985 there have been zero maintenance problems. Consistent with US Air Force regulations for hazardous areas the CORAYVAC ® system is equipped with an outside air supply system. The safe, quiet, draft free CORAYVAC ® heating system keeps planes, mechanics and techni- cians warm and comfortable even during cold Pittsburgh winters. Air Frame and Jet Modification and Maintenance Center, Travis AFB, CA As with many hangars of this type, overhead cranes are in constant use. Because a CORAYVAC® heating system consists of many burners firing in a series it creates an even pattern of radiant heat. This allowed the system to be installed around the perimeter of the building keeping the entire inside area warm. According to U.S. weather data, last winter was the coldest on record for Travis Air Force Base, getting down to 19° F. Even at those low temperatures the Base Engineer, Mechanics and Technicians reported short shirt sleeve comfort anywhere in the CORAYVAC® heated buildings. USAF Corrosion Control Hangar, Mather AFB, Sacramento, CA Old reliable B-52’s are still doing a bang up job for the U.S. Air Force. The CORAYVAC® installed in this corrosion control paint hangar is electronically controlled so that it is turned off when the painting and exhaust systems are turned on. By pre-warming the aircraft, the paint flows onto the surface more evenly and has better adhesion. Delta Airlines - Salt Lake City The above drawings and following photographs show Delta Airlines’ CORAYVAC ® heated hangar facility in Salt Lake City, Utah. This building consists of a hangar, machine shop and a “cabin service area” where they store soft drinks and snacks for passengers. The hangar portion is 287 ft. wide x 175 ft. deep with a roof that slopes from 104 ft. down to 83 ft. This area is heated with 52 model CORAYVAC® B12 burners each firing at 120,000 BTU/hr. for a total input of 6,240,000 BTU/hr. To satisfy local code requirements, three 1,134,000 BTU warm air heaters were mounted near the ceiling. Their thermostats are set lower than the CORAYVAC ® thermostat so they are only used if severe cold weather conditions occur and the large door is open for a long time. The CORAYVAC ® systems slope towards their vacuum pumps and are mounted 75 to 78 ft. above floor level. Even at t his mounting height the workers can feel the warm gentle heating rays at floor level. Because CORAYVAC ® systems heat objects, the floor, planes and tools there is less wasted heat stratification near the ceiling. The low intensity infrared heat rays also melt snow and ice off planes in a hurry. Another extra benefit has been mentioned, and that is the fact that CORAYVAC ® is quiet. Some hangar workers say that the large warm air heaters with large fans are very noisy and fatiguing. They appreciate the silent, draft-free warmth of the CORAYVAC ® system.                  Northwest Airlines, Memphis, TN This is another example of one of over 800 hangars heated with CORAYVAC® in North America. Pilots, mechanics, airplane owners and airport managers familiar with CORAYVAC ® consis- tently recommend it to others. CORAYVAC ® has earned a fine reputation for providing low cost comfort while operating for many years with no maintenance problems. Baggage Train Facility, Memphis/Shelby County Airport, TN “Some baggage handlers have it made,” is what some visitors say when they tour Northwest Airlines baggage train unloading round table at the new Memphis/Shelby County Airport in Mem- phis, Tennessee. On cold winter nights its nice come in under “synthetic sunshine” report the tractor drivers. “We are not sure how many more miles our passengers can get out of their luggage, but we know it helps to use CORAYVAC ® warmed and dries carts.” As you can see, the CORAYVAC® system was nestled up between the beams. Besides warm- ing the baggage trains and drivers, it also helps to keep the ice and slush melted off the floor. Because many burners can be connected to one CORAYVAC ® vacuum pump, very few exhaust openings needed to be made in the walls. Weyerhauser Corporate Hangar, Seattle, WA One glance and you know the Weyerhauser Corporation cares about their operation costs. Smooth, shiny oil proof floors, sky lights in the roof plus translucent panels high in the side walls provide free daytime lighting. A high efficiency CORAYVAC ® heating system mounted in the ceil- ing provides low cost heat. Due to CORAYVAC’S continuous deep reflector design, it is A.G.A. design certified, for mount- ing as close as 4” below combustible materials such as wood structural beams. Heating system designers appreciate the fact that CORAYVAC ® systems consist of several small input burners firing in a series resulting in more uniform heat distribution. This also reduces the “clearances to combustibles” below the system allowing high aircraft vertical and horizontal stabilizers to be “paint safe” under lower, properly designed heating systems. MBB Helicopter Assembly Plant Walk through this MBB Helicopter Assembly Plant and you will be impressed with its clean, efficient operation. Top grade technicians assemble these beautiful “Chopper” using the most precise tools and sensitive gauges. Stringent quality controls insure fail-safe operation. MBB Helicopters use CORAYVAC ® because they cannot afford to have dust interfere with assembly and testing. Traditional heating systems with air blowers spread dust and grit, and are much noisier than CORAYVAC® . CORAYVAC® allows MBB Helicopters to maintain “hospital clean” conditions throughout their facilities in both the U.S. and Canada. CORAYVAC ® Heats Philadelphia Airport Terminal “A” Ticketing Area ECONOVAC® Heats American Airlines Hangar at LaGuardia Airport, NYC Federal Express, Salt Lake City, UT Besides heating Federal Express major Hub Facilities CORAYVAC ® also heats many “City Stations” like this one. In most cases engineers first calculate the heat loss of the building and then specify the quan- tity of heat needed to adequately match the heat loss. However, in this case the CORAYVAC ® system was designed to heat only the area around the sorting belt. This kept installation and operating costs to a minimum. Besides the sorting are CORAYVAC ® is used in the truck service are of Federal Express “City Stations” where the system is designed to match the heat loss. Here again mechanics who previ- ously worked elsewhere under other types of heat report they are more comfortable under CORAYVAC ® . Snow Melting, Parking Ramp, Denver, CO With new larger terminals handling 20 to 30 million passengers per year, the cost of land esca- lating up beyond reason , and airports being located further beyond city limits, it becomes in- creasingly important to consider building multistory parking ramps. In cold areas, ice on parking ramp inclines can be problem. This photograph shows how a parking ramp in downtown Denver solved their problem with Roberts-Gordon radiant heat. Airport Runway Maintenance Vehicle Garage, O’Hare Airport Chicago’s O’Hare Airport is one of the busiest airports in the world, handling over 1,000 flights a day. If and when it shuts down, it affects the entire national and international air transportation system. O’Hare Airport is also located in a cold climate zone where winters are known to be severe. Runway maintenance equipment must be “able to roll” at a moments notice anytime, day or night, weekdays and weekends. That is why the CORAYVAC® heating system was selected. Mounted at ceiling height, where no floor space is required, CORAYVAC beams its gentle heat down to warm the floor, snow removal equipment and mechanics. When a plow is out of service, it must be repaired immediately. The CORAYVAC® melts ice and snow off the truck in short order. Shirt Sleeve comfortable mechanics are then able to quickly determine the cause of the problem and fix the vehicle. One other consideration in this facility was the fact that cold ice packed sand in roadway sand- ing trucks does not always flow smoothly through the sand dispersal mechanism. This results in uneven coverage of the roadways. Under CORAYVAC®, the sand stored in the trucks is warm and fluid. In the garage shown above, CORAYVAC® input is calculated at 80% of the building heatloss and is the primary heating system. The make up air system is on a time clock which operates when people are in the building. Make up air input is calculated to meet code requirements of 2 CFM per square foot. The result of the CORAYVAC® system are clear: • Snow melts off vehicles fast. • Floors are warm. • Fast heat recovery after trucks come in and doors are closed. • No maintenance. Ground Support Vehicle Service Building, Pittsburgh, PA CORAYVAC ® maintains quiet warmth in garages housing expensive de-icing and freight han- dling equipment. The even radiant heat keeps floors and vehicles warm and dry. Mechanics report the quiet, draft free comfort produced by CORAYVAC ® is far superior to any other type of heating systems they have worked under. Airport Fire/Rescue Station, Seattle WA Airport Emergency vehicles must be able to respond immediately when needed. Saving min- utes means saving lives. That’s one reason why hundreds of emergency vehicle stations are heated with CORAYVAC ® . The radiant heat keeps diesel and gasoline engines warm and allows them to start quickly. Water and foaming agents in the tanks stay at consistent ready-to-use warm temperatures. When ice covered vehicles return to the station, the CORAYVAC ® heat melts ice and snow quickly making the vehicles “emergency ready” in a very short time. Entrances to stores, passengers terminals and customer pick-up area’s can be ideally heated with our gas fired, low intensity infrared heating system mounted over decorative alu- minium grille in drop ceillings. Besides providing incoming people with a feeling of warmth, the radiant heat beams down to warm and dry the floors during inclement weather. AviationFacilities Heating Basics of Infrared Heating All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating Basics of infrared Heating What is infrared? Infrared is the transmission of energy by means of electro magnetic waves (rays). When rays strike an object, they stimulate the molecules within the object, causing them to move rapidly and to gener- ate heat. Infrared rays are invisible and travel at the speed of light in straight lines from the heat source to all surfaces and objects without heating the space (air), through which they pass. energy in the rays is safely absorbed by cool surfaces (floors, equipment, people), and conduction carries some of the heat deeper into surfaces, creating a reservoir of heat. The balance of the radiant energy is reflected from the heated surfaces to be absorbed by other cooler surfaces. The tempera- ture of the air is raised by convection from heated surfaces. Infrared heating equipment is mostly available today in two forms: 1. High Intensity Equipment 2. Low Intensity Equipment High intensity equipment, identified by an open flame and high temperature (1800 °F) ceramic surface, is what many engineers associate with the term “infrared heat.” This type of equipment is mor suitable to a localized heating or “spot” heating application and represents only a small portion of the infrared heating equipment available to the heating system designer. Low intensity equipment, identified by a flame contained within a tube or network of tubes at a reduced temperature (maximum 900°F - 1000°F), is now recognized as being an efficient means of heating an entire space. Heating a continuous span rather than a series of intermittent spots pro- vides a level of comfort surpassed only by the sun. Electromagnetic Spectrum The Electromagnetic spectrum differentiates all known types of electromagnetic wave energy vis their wavelength as measured in microns. The shortest wavelength energy (1 x 10-8 microns) known as the cosmic ray, while the longest wavelength energy (5 x 108 microns) known is the broadcast radio wave. Visible light falls between these two extremes, having wavelengths between 0.4 and 0.7 microns. Infrared energy waves are slightly longer than visible light, having wavelengths from 0.7 to 400 mi- crons. However, the majority of heat producing radiant energy falls within a much narrower wave- length range of 2 to 12 microns. It is important to consider the heat energy wavelength for the follow- ing reasons: a.) The wavelength is directly related to the emitter source temperature, with higher temperature sources generally producing a majority of the energy at shorter wavelengths. b.) The energy transfer to the solid body receiver can be affected by wavelength. Many materials more completely utilize energy provided at longer wavelengths (for example: concrete, water.) The Electromagnetic Spectrum picture illustrates the electro magnetic spectrum as it is known today. The Infrared Spectrum picture illustrates the infrared spectrum relative to common types of infra- red heating equipment available today. Unity of Infrared Nearly all manufacturers, designers, and users of radiant heating equipment agree that radiant heating can accomplish the same space heating job with less energy input than a convective heating system. To better understand these results, it is necessary to review the manner in which radiant heating and convective heating appliances warm a space. Convective Heating Convective heating systems such as unit heaters or central furnaces deliver heat by first heating air to higher than comfortable temperatures. This hot air is then delivered to the space, either directly or through ducts, where it is then mixed with colder air. The warmer space air is supposed to heat occupants and objects by direct contact. While appropriate for small spaces such as offices and residential units, convective heating has many disadvantages in large-space applications: • Hot air tends to rise in a space. When ceiling heights are higher than normal, much of the warm air rises to the ceiling where it is not needed. This is called stratification. • Some of the hot air is lost immediately through exfiltration before it has a chance to mix with colder air. • Open doors, windows, etc., can drain a space of warm air within a matter of seconds. Heat recovery time can be very slow because the air must be heated over again. • Convective air requires large amounts of air movement to work properly. This excess circulation is not only noisy, it helps spread dirt, grit, dust, pollen, and airborne bacteria and fungi. Radiant Heating Infrared energy from a radiant appliance heats objects, people and surfaces, not the air. The warm objects and floor convert this energy to heat which: • Is absorbed into the objects and the floor, creating a heat reservoir. • Warms the air near the objects and floor via convection. • Is reradiated to occupants and other surfaces of the spaces. The radiant energy received by the occupants, directly from the heater or indirectly from the heater via reradia- tion by the floor and objects, serves to increase the mean radiant temperature (MRT) of the occupant. In a manner similar to direct sunlight, the increased MRT allow the occupant to perceive a comfort condition at a much reduced air temperature (sometimes as much as 7° - 10°F lower.) The resulting reduced air temperature within the space provides the following advantages: • Reduced stratification of air within the space. • Reduced actual transmission heat loss due to lower temperature inside than assumed design condition, as well as substantially lower ceiling and upper sidewall temperature due to reduced stratification. (25° - 30°F lower is not unusual.) • Reduced air change heat loss, to the extent that exfiltration through cracks or openings, near the roof, will be decreased due to decreased stack effect. • Decrease the actual degree days experienced. Each of the above advantages impacts favorably on fuel usage. Methodology of Radiant Heating Appliances All radiant heating appliances are not the same. Various material properties and performance criteria can be used to evaluate a radiant heating appliance relative to its major function, namely: • Provide usable radiant energy to the space in sufficient quantity to provide comfort for the occupants. Figure 1 is a visual representation of the factors that effect the performance of a radiant appliance. These few factors are reviewed briefly below. Natural gas or L.P. fuel contains an inherent chemical heating value (approximately 100 BTU/cubic foot for natural gas and 2500 BTU/cubic foot for L.P. gas.) Of this total heating value available, only a percentage is available to the radiant heating appliance, the remainder being stack loss. This percentage is known as thermal efficiency and is described as follows: Thermal Efficiency = Total Input Energy - Stack Loss The tube is heated by the available energy from the fuel gas. A tube material property, called emissivity, helps determine the amount of energy that leaves the tube as radiant energy. The heat energy of the tube is dissipated by one of the following mechanisms: 1.) A portion of the energy is released as radiant energy directly to the space. 2.) A portion of the energy is released as radiant energy and is reflected by the fixture to the space. 3.) A portion of the energy from the tube is convected to the space. 4.) A portion of the energy is released tot he fixture and “bound back” into the tube. The fixture efficiency is a measurement of the ability of the heating appliance to release radiant energy to the space. Note that the relationship of items 1 through 4 above can greatly influence the fixture efficiency. Equally influential to the fixture efficiency is the reflector material and the reflector shape. The property of the reflector material, known as reflectivity, and overall configuration of the reflector determine the amount of usable radiant energy delivered to the space. The pattern efficiency of a radiant heating appliance is a measurement of the ability of a radiant heating fixture to deliver energy into a usable, specific distribution pattern in the space. it is this distribution pattern, together with a material property of people or objects in the space known as absorptivity, that determines how much of the radiant energy released by the heating appliance is utilized by the space to provide comfort to the occupants. For comparison purposes, Figure 2 provides a visual representation of the methodology for a conventional air heating appliance.                !" ! #$" $ %" $ &" #% #' ( ) *+ , -  + .  + ( )     !# -  / 0 (   + 1      #  2(   + 1     #% #' %    #% #' % $# 3 4 +3 2.  0   !! "# $%&''( )%&''( *!+ ,,!' -*'. /'/-                    AviationFacilities Heating Types of Radiant Heating Equipment All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating Types of Radiant Heating Equipment ASHRAE Defined Types All radiant heating appliance are not the same. A recognized method of classifying radiant heating systems is according to the operating temperature of the emitting surface. For example: 1. High and Medium Intensity 1500°F and above 2. Low Intensity 500°F - 1500°F 3. Low Temperature 120°F - 350°F High and medium-intensity heaters usually take the form of open flame, unvented appliances with incandescent faces. Low intensity units redesigned to operate below incandescent temperatures and frequently use steel tube or pipe as an emitter. Low temperature radiant heating systems utilize large heated surfaces such as floors, walls, panels, or ceilings. The surface temperature is elevated by hot water piping or electrical resistance wire embedded in the surface. ASHRAE recognizes three specific types of infrared heaters that are gas-fired: Type 1: Indirect Fired Units Type 1 is characterized by burning a gas-air mixture inside a tube or enclosure, which radiates its energy to the space. The products of combustion are generally vented to the outside. Typi- cal operating surface temperatures do not exceed 1200°F. Type 1a units utilize an atmospheric burner venting product of combustion upward. (for ex- ample, a patio heater) Type 1b units utilize multiple vacuum assisted burners operating in a horizontal tube. Type 1c unit utilize a power assisted (force draft) burner operating in a horizontal tube. Type 3: Catalytic Units Type 3 is characterized by mixing gas and air in the presence of a catalyst. The mixture oxi- dized without flame, and heat radiates into the space. The products of combustion are vented into the space. Temperatures of these catalytic units range from 650°F - 700°F. Type 2: Direct Fired Units Type 2 is characterized by burning the gas-air mixture in a porous matrix of refractory material, which radiates its energy into the space. The products of combustion are vented into the space. Temperatures of operating Type 2 units range from 1600°F - 1800°F. Description Engineered, custom designed, multiple burner, condensing appliances. Engineered, custom designed, multiple burner, non-condens- ing appliances. Factory assembled, single burner, non-condensing appliances. Site-assembles, single burner, non-condensing appliances. Factory assembled, open flame. Factory assembled, catalytic combustion. Appliance Type Type 1b Quasi-Type 1b/1c Type 1c Quasi-Type 1b/1c or Type 1C Type 2 Type 3 Market Defined Types The ASHRAE defined radiant heating appliances do not adequately reflect the recent evolution of new products as available in the marketplace. The result is that the industry has moved beyond these definitions by introducing new appliances that fall into more than one of these categories. In addition, ASHRAE has not yet developed a way for the engineering community to distinguish between appliance performers within a category or be- tween a category. The most visible demonstration of this definition inadequacy exists within the increasingly popular ASHRAE Type 1b an Type 1c appliance market. Recently introduced radiant heating appliance have many characteristics of a Type 1b system, but not all of them. Specifically, lower efficiency of these systems do not provide for condensation of the combustion gases before exhaust. Additionally, many manufacturers combine multiple, individual, non-condensing burner appliances on a common exhauster and represent the resulting system as a Type 1b condensing appliance. The lower efficiency of these systems more accurately reflects the performance characteristics in- herent in a ASHRAE Type 1c appliance. In order to differentiate these appliances, the market has defined a radiant heating appliance category between an ASRAE 1b and 1c. Burners in this category are referred to as Quasi-Type 1b/ 1c appliances. Variation in market approach can be recognized as follows: AviationFacilities Heating Concepts of CORAYVAC ® All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating Concepts of CORAYVAC® Concept The concept of CORAYVAC® is easy to understand. However, ti often means discarding old ideas because CORAYVAC® is a different kind of heating system. The things that make it different, make it better. CORAYVAC® is a gas-fired, vacuum operated, low intensity radiant heating system incorporating a pateneted incremental burner system. Gas-fired means it is fired with clean burning Natural or LPG gas. Vacuum operated means that the vacuum pump draws all the products of combustion through the system ans completely expels it safely outdoors. Low-intensity means the radiant surfaces of the heat exchanger tubes do not glow red, instead they operate a a lower temperature (less than 900°F) and radiate heat at lower intensity per square foot of radiating surface. Area coverage is provided by radiant heat from long runs of 4” O.D. steel tubing which are suspended from the ceiling on roof suppports. Reflectors are provided to direct the radiant heat downward to occupied areas. Radiant refers to the heat radiated by the CORAYVAC® system. Because this heat is in the form of infrared rays, it does not directly heat the air. Instead, the rays heat objects such as the floor, cars, ma- chines and people. The objects in turn heat the air. Incremental burner system means that several burners can be located in a series in a radiant branch and fired in the same run of tubular steel heat exchanger that carries the combustion gases from up- stream burners. Each of these burners in a radiant branch can be selected in terms of firing rate; also, the space between the burners can be adjusted. This permits a matching of heat gain to the heat loss for each area of the building. Firing burners in a series provides higher thermal and radiant efficiency and this is one of the patented features of CORAYVAC® . A major characteristic of a properly designed low intensity radiant system is that the occupants are barely conscious of the radiant heating when the system is firing. They will feel little or no change when the thermostat is satisfied and the system is not firing. This combines the warm floors and draft free operation to improve the mean radiant temperature of the space which are the keys to the high comfort level and fuel utilization efficiency provided by CORAYVAC® heating. The CORAYVAC® System Each CORAYVAC® installation consists of one or more vacuum pump systems. Each of these consist of one vacuum pump, a pre-wired control panel, thermostat controls and a number of burner modules. It also includes the extended heat exchanger surface in a form of 4” O.D. steel or porcelain lined tubing or Schedule 40 black iron pipe with high efficiency aluminum reflectors over this heat exhcanger to reflect the radiant heat downward to the floor. The heat exchanger section nearest the the burners radiantes with the most intensisty and is called radiant pipe. This should be located over areas with the grates heat loss. The balance of tubular or Schedule 40 pipe heat exchanger surface radiates with less intensity and is called tailpipe. This can be located in areas with lower heat loss. There are minimum lengths of tailpipe prescribed in the design requirements. It is essential that these minimums be provided if the pump capacity is to be maintained and the best thermal effi- ciency is to be acheived. While it is important to locate radiant tubes and tailpipe over areas with high heat loss, such as the perimeter of the building, it is not always essential to cover all areas directlty with radiant heat. Center areas and other areas of low heat loss can be adequately heated without direct coverage if the input system is adequate for the total building. However, in order to acheive the highest degree of comfort and fuel savings, it is recommended that the CORAYVAC® system be located to provide as complete and even a distribution as is practical. Diagram 1 illustrates componants od a typical CORAYVAC® system. Safety Safety has been a prime consideration in the design of the CORAYVAC® system as can be deter- mined from a review of system features. This includes a pre-purge of the complete tube network with air prior to flame ignition. In each burner, there are two valves in a series that must be energized as well as the zero regulator. These devices, together with a vacuum pressure switch, ensure that there will be no gas flow unless the vacuum pump is operating. Additionally, slow opening gas valves provide smooth ignition and enhance reliability. With CORAYVAC® , all equipment controls are A.G.A. gas design certified, both as individual parts and also as a complete heating system. Also, individual electrical componant parts are UL listed as applicable. Zero Regulator CORAYVAC ® uses a 100% pre-mix burner with the input dependent on system vacuum. It is the only ture vacuum operated system available today in that both air and gas are pulled into the burner head by system negative pressure. With no vacuum, the zero regulator prevents gas flow. When vacuum is present, the burner fires and input increases ans vacuum increases. As the input in- creases, the amount of air also increases. Over the normal range of operating vacuum, the gas/air ratio is essentially linear. This unique and patented feature provides optimum combustion conditionas at all times and is unaffected by fluctuations in fuel pressure, dirty air filters, changes in atmospheric pressure, wind velocity or other climatic conditions.                                        !"  #" $ % & '(                    $  #    %      %  " 0  "           % '   Figure 5: Illistrative View of CORAYVAC ® System with One Vacuum Pump NOTES: 1.) Damper coupling is required where the layout is asymmetrical (i.e. unequal flow unit from each burner branch. 2.) Reflectors and support system not shown. 3.) The radiant pipe is joined with unlined couplings. The tailpipe is porcelain lined and joined with lined couplings. Safety Most manufacturers, designers, and users of radiant heating equipment agree that the same space heating job can be accomplished with les input capacity with a radiant heating system than with convective heating systems such as unit heaters or central furnaces where heat is delivered by movement of heated air. To better understand these results, it is neceassary to review the manner in which a radiant heating appliances warms a space. Infrared energy from a radiant appliance heats objects, people and surfaces, not the air. The warm objects and floor convert this energy to heat which: • Is absorbed into the objects and floor creating a heat reservoir. • Warms the air near the objects and floor via convection. • Is reradianted to occupants and other surfaces of the space. The radiated energy received by the occupants, directly from the heater or indirectly from the heater via reradiantionf from the floor and objects, serves to increase the mean radiant temperature (MRT) of the occupant. in a manner similar to direct sunlight, the increased MRT allows the occupant to perceive a comfort condition at a much reduced air temperature (sometimes as much as 7° - 10°F lower.) The resulting reduced air temperature within the space provides the following advantages. • Reduced stratification of air within space; • Reduced actual transmission heat loss due to lower temperature inside than assumed design condition, as well as substantially lower ceiling adn upper sidewall temperature due to reduced stratification (25° - 30°F lower is not usual); • Reduced air change heat loss, to the extent that exfiltration through cracks or openings, near the roof, will be decreased due to decreased stack effect. • Decreases the actual degree days expreienced. Each of the above advantages impacts favorably on fuel usage. Selecting the Burners The number of burners and firing rate for each must be specified for each design layout. In addi- tion, an end vent plate must be provided for each end burner and this to match the firing rate of the end burner. The selection of a burner rate should be made foe each burner position according to factors such as: • Heat gain required and didtribution of same. • Mounting height available. • Flow loading restrictions. • Length of radiant branches. • Distance required between burners. • Desired radiation intensity. In general, lower burner rates can be used for lower mounting heights or where lower heat gains are required. Higher burner rates are uased primarily with higher mounting heights or where high heat gain is required. The quantity of burners required can be calculated by dividing the input rating of the selected sizes into the calculated CORAYVAC® system required installed capacity. Flow Loading The patented CORAYVAC® burner system allows a number of burners to be installed in series, in same radiant tube, resulting in a long, continuous radiant emitting surface, to give even heat distribu- tion within the building. To enable the burners to be correctly located within the tube, to maintain system operatingvacuum and obtain design flue gas temperatures at the vacuum pump, the design layout is based on a simplified flow principle using a “flow unit.” The flow unit is defined as the amount of fuel/air mixture for a heat input rate of 10,000 BTU/Hr. This corresponds to a flow rate of 1.83 cfm at 65° - 70°F. For the purpose of design, flow units are considered to ener the CORAYVAC® system in one of two ways: • Through the burner. • Through the end plate. and exit the system as spent products of combustion via the vacuum pump. Table 1 lists the flow unit values associated with each burner firing rate, its associated end vent, and minimum flow unit requirement entering a combustion chamber. Figure 6 summarizes design and flow loading parameters for CORAYVAC ® systems. The purpose of the end vent air is to provide that part of the burner inlet flow required to dilute the hot combustion gases at the burner therby promoting uniform heating of the tube while avoiding excessive heating of the combustion chamber. For the end burner, the burner inlet flow consists of the total of the end vent air plus the combustion gases from all upstream burners. The requirments for minimum burner inlet flow is met if the inlet flow units entering the combustion chamber meets or exceeds the minimum as shown in Table 3. Tadiant Branch Flow The flow ina radiant branch consist od the end vent flow units plus the flow units of combustion air from all burners. The limiting factor for maximum flow in the radiant section has been determined experimentally in terms of the maximum burner inlet flow units that can be tolerated without degradation of combustion characteristics at the last downstream burner. Also, if more thanthe maximum number of burners are installed per radiant branch, the vacuum loss across the additional burners will increase appreciably. This maximum flow in the radiat branch can be expressed for each burner firing rate by either a maximum number of burners per branch or the corresponding maximum number of flow units. Refer to Figure 6. Figure 6: Design Parameters Burner Model No. B-4 B-6 B-8 B-10 B-12 Input BTU/Hr (1000’s) 40 60 80 100 120 Flow Units per Burner 4 6 8 10 12 Flow Units per End Vent 10 15 20 20 20 Maximum No. Burners per Branch 4 4 3 3 2 Maximum Flow Units per Branch 26 39 44 50 44 Radiant Tube Lengths Min. 12.5 ft. 20 ft. 25 ft. 30 ft. 35ft. (Distance between Burners) Max. 25 ft. 35 ft. 45 ft. 60 ft. 70 ft. Tailpipe Length per Flow Units Min. 1.2 ft. 1.2 ft. 1.2 ft. 1.2 ft. 1.2 ft. Max. 3.0 ft. 3.0 ft. 3.0 ft. 3.0 ft 3.0 ft. Minimum Tube length from Burner Downstream to Elbow 5 ft. 10 ft. 10 ft. 15 ft. 15 ft. Upstream to Elbow 2 ft. 2 ft. 2 ft. 2 ft. 2 ft. Suggested Minimum Mounting Height 8 ft. 8 ft. 10 ft. 15 ft. 15 ft. Table 1: Flow Unit Specifications Model Flow Unit Flow Units Minimum Flow Units Entering per Burner per End Vent Combustion Chamber CRVB-4 4 10 10 CRVB-6 6 15 15 CRVB-8 8 20 20 CRVB-10 10 20 20 CRVB-12 12 20 20 Installed Altitude Maximum Installed Altitude Maximum (above Sea level) Capacity (above Sea Level) Capacity 0 - 2000 ft. 110 flow units 5001 - 6000 ft. 90 flow units 2001 - 3000 ft. 105 flow units 6001 - 7000 ft. 85 flow units 3001 - 4000 ft. 100 flow units 7001 - 8000 ft. 80 flow units 4001 - 5000 ft. 95 flow units 8001 - 9000 ft. 75 flow units Tailpipe Flow Excessive flow loading in a single section of tailpipe can cause low vacuum and lower effective pump capacity if care is not taken to observe the necessary design requirements. It is important to check the length of tailpipe for each radiant branch, and verify taht it is within ± 5% of the specified length. If the proper end vent vacuum is to be maintained, the length of the tailpipe must not be excessive for the flow units being carried by that section of tailpipe. Refer to Figure 7 to determine adherence to vacuum line loss requiremets. Vacuum Pump Capacity The flow capacity of the vacuum pump is indicated in Table 2 as a function of installed altitude. When the CRV system is designed in accordance with the last set of instructions and is in proper operating condition, a vacuum from 2 to 3 inched w.c. will be obtainable at each end vent (i.e. at all burners). Table 2: Vacuum Pump Capacity There are a number of critical design requirements which, if not met, will reduce the vacuum ob- tainable and thereby the effective flow capacity of the vacuum pump. These include: • Minimum Length of Tailpipe; if less than the minimum length of tailpipe is provided per radiant branch, there will be insufficient cooling of the combustion gases and improper operation of the vauum pump. • Line Loss Check for Tailpipe is applicable to sections of tailpipe which are common to two or more radiant branches (i.e. shared lengths). See Figure7. • Excessive Back Pressure on a discharge line of a vacuum pump as caused by partial blockage or too much flow for length. • Air Leaks in the system as caused by poor installation, missing view port windows in combustion chambers, leaky burner gaskets, missing or improperly installed end vent plates, poor joints at the couplings, obstruction inside the pipe, or incorrectly set dampers. • More Than Maximum Number of Burners or flow units per raidant branch. • Excessive Number of elbow of tee fittings. If the distance required for the tailpipe to reach the pump position of the system is greater than allowed, then there are some alternatives: a. Use separate branches of reduced flow units for half the distance and then tee together for the balance of the run. b. Use separate branches from the pump each with less flow units. Then each branch could be longer than required. Figure 6: Vacuum Line Loss Requirements for Tailpipe NOTES: - Readings for length and flow when plotted on a graph must fall on the OK side to avoid excessive vacuum losses. - Lengths shown include allowance for 1 elbow every 50 ft.; deduct 15% of lenggth for each additional elbow used per 50 ft. of length. Heat Exchanger Surface The main purpose of the tailpipe and the radiant pipe is to provide sufficient heat exhcanger sur- face to transfer the heat from the flue gases to the tube wall where it can released from the outside surface of the tube as useful heat. Radiant pipe is defined as the tubing between burners firing in a radiant branch, plus the radiant tubing immediately following the last downstream burner. Tailpipe is defined as all the tubing between the radiant pipe and the vacuum pump. Most of the radiant heat supplied by each burner is released from the outside surface of the radiant pipe; the balance is released by the tailpipe. The placement of radiant pipe to correspond to areas of major heat loss is the key to providing uniform comfort levels. The use of adequate tailpipe is the key to high combustion efficiency and proper operation of the vacuum pump. Radiant Pipe The considerations in selecting the length of the radiant pipe include the following: Minimum - This provides for the highest level of average intensity per foot of radiant pipe and good uniformity between burners. This requires more tailpipe to maintain operating efficiency and pump capacity. Maximum - This provides the lowest average value of intensity per foot of radiant pipe and consequently the largest span between burners. The intensity will be reduced slightly for the last 5-10 feet of radiant pipe before the next burner. The length of radiant pipe required for burners varies according to the firing rates. Also, consider- ation has been given to usage of a standard 10 ft. or lengths that can be cut from same without waste. Refer to Figure 6. When positioning radiant pipe to give the required radiant distribution it is important to consider: • Clearance to adjacent combustive materials. • Lighting equipment. Tailpipe The considerations in selecting the amount of tailpipe include the following: Minimum - This is the minimum length of tailpipe to cool the flue gases sufficiently for proper operation of the vacuum pump. Excessive temperatures at the inlet to the pump will reduce the effective flow capacity and the vacuum abtainable system. Maximum - The maximum limit established for the amount of tailpipe that can be used is defined in Figure 8. This permits the use of an extended connecting length of tailpipe is a branch of burners is remotely located which would otherwise require a seperate vacuum pump. It should be noted that if there are traces of corrosive contaminents in the combustion air, much of this longer section of tailpipe will be exposed to corrosive conditions due to low temperature in the end of the tailpipe. In regard to the length of the tailpipe required per flow unit, there is a trade off between length of radiant pipe and length of tailpipe. Consequently, the requirements for tailpipe are stated below. Tailpipe Length (with maximum length of radiant pipe) Minimum 1.2 ft./Flow Unit Maximum 2.5 ft./Flow Unit Tailpipe Length (with minimum length of radiant pipe) Minimum 2.0 ft./Flow Unit Maximum 3.0 ft./Flow Unit Figure 7 establishes a nominal length relationship between radiant pipe and tailpipe for each burner firing rate based on a mid-range thermal efficiency for condensing systems. Figure 9 relates the effect on system thermal efficiency of variations in radiant tailpipe lengths. Note: When accounting for the required tailpipe lengths during the design process, it is important to verify that the tailpipe for each branch is at least equal to the specified minimum. For radiant branches which are served by sharing tailpipe sections, the shared sections can be allocated to either branch with any distribution of length. The objective is to allocate the shared section in a way which permits the minimum length requirement to be met ofr all radiant branches served by that shared section. The prime consideration is that each foot of shared section can be counted only once. Figure 7: Nominal Radiant/Tailpipe Requirements )*+ ,*- .*+ /*- 0*+ +*- #*+ )*- -*+ .*- 1*+ 0*- #*+ ##*- #,*+ #-*- #/*+ #*+ #* #*# #*) #*, #*- #*. #*/ #*1 #*0 )*+ )* #*#- 234 5 '62 6   2 !78& 234 5 6 6   5 9 26 !78& + + - - #+ #+ #- #- )+ #- 6 6  2348 5 2'28623 7' 6 6  2348 5  27% 7' Note: When accounting for the required tailpipe lengths during the design process, it is important to verify that the tailpipe for each branch is at least equal to the specified minimum. Air Supply System An air supply free of dust and corrosive contaminants is essential for proper operation and best life expentancy with any heating system. With Co-Ray-Vac there are two alternatives available to the designer for providing the air supply. These are: - Individual filter for each burner. A single filter door is standard for each burner. - Outside air system to duct air from an uncontaminated source. A single filter for each burner is used plus outside air supply to provide both combustion and end vent air. it must be determined that outside air is not contaminated by exhaust from the same building and/or neighboring buildings. The first alternative above, is usable when the dust load is not excessive and there is not usage of corrosive contaminants such as solvents or vapors inside the building or in close proximity to the building. Vapors in close proximity could include exhaust air from a nearby factory such as chemical plant, a dry cleaner establishment,etc. The second alternative must be used in all applications where corrosive contaminants my be present in the air in trace amounts (few parts per million) for several days or more per year during the heating season. It is important for designers and owners of heating systems to note that the presence of traces of corrosive contaminants in the combustion air supply will greatly accelerate the rate of corro- sion on heat exchanger surfaces and will shorten the useful life of the heating system accord- ingly. This is true regardless of wheather the heating system is Co-Ray-Vac, other infrared systems or conventional gas or oil fired equipment such as unit heaters, central boiler plant, etc. Vith Co-Ray-Vac it is practical to provide an air supply system for filtered combustion air with- out any possibility of upsetting the fuel air mix as the filter loading increases. With the unique vacuum powered burners, the fuel air mix rate remains constant. It can be expected that the use of an outside air system will reduce but not eliminate the corro- sion. In a way similar to the Co-Ray-Vac vacuum pump system also involves considerations os total flow units and acceptable combinations of duct lengths (and diameters) versus flow units car- ried. In certain circumstances it may be desireble to produce a fresh air inlet fan to pressurize the system. The small positive pressure is desirable and necessary to prevent the system from drawing in contaminated air. To size each section of pipe proceed as follows: 1) Calculate the required flow units at each outlet of the supply system. 2) Measure the longest run of pipe from thr blower to the most remote outlet. Use only this distance in figure 8 (or the next longer distance if the exact distance is not shown). This is to provide assur- ance that the preassure drop to the most remote outlet will not exceed 0.25” w. c. when all outlets are supplied. 3) To use figure 8, find the intersection point on the graph for the appropiate duct length and num- ber of flow units. The duct size line above this intersection point indicates what size duct work should be used. Proceed in a similar manner for each outlet and each section of duct. For each section of duct, determine the total flow unit capacity supplied by that section. Figure 8: Air Supply System Capacity by Lenght and Diameter (Based on 2.25” W.C. Maximum Line Loss) *%1'-23        4    !56 ' ' ' ' 1' 17% 89 %','(%:%7 !%%5; 4'+' AviationFacilities Heating Heat Loss and Annual Fuel Use Calculations All claims related to gas-fired, low-intensity heating are predicated on the equipment being designed, installed, maintained and serviced properly by a qualified professional. Installation Code and Annual Inspections: All installation and service of ROBERTS GORDON® equipment must be performed by a contractor qualified in the installation and service of equipment sold and supplied by Roberts-Gordon LLC and conform to all requirements set forth in the ROBERTS GORDON® manuals and all applicable governmental authorities pertaining to the installation, service and operation of the equipment. To help facilitate optimum performance and safety, Roberts-Gordon LLC recommends that a qualified contractor conduct, at a minimum, annual inspections of your ROBERTS GORDON® equipment and perform service where necessary, using only replacement parts sold and supplied by Roberts-Gordon LLC. Further Information: Applications, engineering and detailed guidance on systems design, installation and equipment performance is available through ROBERTS GORDON® representatives. Please contact us for any further information you may require, including the Installation, Operation and Service Manual. These products are not for residential use. This document is intended to assist licensed professionals in the exercise of their professional judgment. AviationFacilities Heating Building Heat Loss and Sizing the System The building heat lost must be calculated in strict accordance with the current ASHRA (American Society of Heating, Refrigeration, and Air Conditioning Engineers) Guide. The Co-Ray-Van system is determined in concert with the required radiant adjustment to heat loss and height adjustment factors. Radiant Adjustments to Heat Loss The practice of applying and adjustment factor to heat loss calculations for radiant heating sys- tems is well known within the radiant heating industry, having been used by manufacturers for over 25 years. Recently, a number of studies have been conducted to identify the values of the adjustment factor in the range of 0.8 to 0.85 depending on efficiency (higher efficiency uses lower factor). This adjustment can be more thoroughly understood when considering the following radiants effect is- sues: Infrared energy heats objects, not the air; Lower ambient air temperatures reduce the amount of air infiltration; Less air stratification with radiant heat; Lower ambient air temperatures reduce the transmission heat loss across walls and roof; Elevated floor temperatures provide a thermal reserve capacity; Increased mean radiant temperature allows occupants to perceive thermal comfort at all the reduced air temperature. Each of these issues impact favorably on the utilization of the installed capacity of the radiant heating system. This fact, together with the realization t