BASE BID:
SECTION 15542 – FUEL-FIRED RADIANT HEATERS
PART 1 - GENERAL
1.1 SUMMARY
A.
Furnish and install a Co-Ray-Vac Low Intensity Vented Infrared Radiant Vacuum Gas Heating System.
System must be certified as a system by the American Gas Association under American National
Standards for vented infrared heaters. System must be vacuum vented to atmosphere and be under
negative pressure at all times during operation to preclude possibility of escape of combustion gases
inside building
1.2 SUBMITTALS
A. Product Data: Include rated capacities, furnished specialties and accessories.
B. Shop Drawings: Detail fabrication including anchorages and attachments to structures and to
supported equipment. Include auxiliary motor slides and rails and base weights.
1. Wiring Diagrams: Power, signal, and control wiring.
C. Field quality control test reports.
D. Operation and Maintenance data
1.3 QUALITY ASSURANCE
A. The heating systems supplied shall be design certified by the American Gas Association and
this per American National Standard Z83.6-1982 “Vented Infrared Radiant Heater”.
B. Each burner shall have a nameplate affixed that bears the seal of the American Gas Association.
C. The manufacturer on request of the purchaser shall supply a copy of the current design
certification to cover the entire system.
D. Clearances to combustible materials shall not exceed those outlined and printed on the burner
nameplate and on manufacturer’s specification sheet as measured from the surface of the radiant
pipe.
E. The combustion system shall be capable of being the combustion condensing type in which the
products of combustion are exhausted below the dew point of the moisture in the flue gases
(140oF - 180oF).
F. Installation of all equipment and materials shall conform to the practices of good workmanship in
accordance with applicable requirements. The combustion chambers, pipe work, gas lines and
electrical conduit shall be attached to or suspended from the building structure in a manner suitable to
meet standards of durability and safety.
G. System manufacturer to supply verification from an independent test laboratory showing that the
entire system is capable of achieving an annual fuel utilization efficiency (AFUE) of 90% or higher.
1.4 WARRANTY
A. Warranty on gas fired radiant systems is to be submitted in writing signed by manufacturer, agreeing
to replace/repair, within warranty period, components of gas fired radiant systems furnished by
manufacturer, which are defective in either material or workmanship, provided manufacturer’s
instructions for handling, installing, protecting and maintaining units have been adhered to during
warranty period. Replacement is limited to component replacement only and does not include labor
for removal and reinstallation. Warranty period - three years from date of substantial completion
for all parts.
2015 Co-Ray-Vac Radiant Heating System – Base Bid Specs
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PART 2 - PRODUCTS
2.1 MANUFACTURERS
A.
Infrared heating system shall be CO-RAY-VAC radiant heating system as manufactured by
Roberts-Gordon, Inc., Buffalo, NY, USA.
B. Other low intensity radiant systems of equal or greater efficiency and with lower capacity, and with the
pattern shown on drawing may be acceptable provided they meet the intent of these specifications and
prior approval in writing is obtained from the Engineer at least ten (10) days before the bid date. If
such systems are approved, the Contractor assumes responsibility for the design, performance and
expense of same. The redesigned system, gas piping, and electric wiring drawings shall be done by a
Registered Mechanical Engineer. Shop drawings of the entire new system shall be provided by the
Contractor. The Contractor shall state the
amount to be credited to the Owner due to this
substitution.
Where substitutes are used, the Contractor assumes all responsibility for physical dimensions
and all other resulting changes. This responsibility extends to cover all extra work as necessitated by
other trades as a result of the substitution.
The Engineer reserves the right to require the Contractor to remove and replace any material or
equipment which does not meet specifications or does not have prior approval as a substitute item.
Work shall be completed immediately without cost or inconvenience to the Owner.
2.2 TUBULAR INFRARED HEATERS
A. Manufacturers:
1. Roberts-Gordon LLC
2. Approved Alternate Manufacturer
B. BURNER UNITS:
1. Each firing unit shall consist of an integral burner control installed in a factory furnished
combustion chamber and shall have a maximum gas input rating as indicated on the
drawing. Burner assembly shall consist of heavy duty cast iron burner head, pre-wired
electronic gas controls with electronic ignition and combustion air filter.
2. Burners shall be designed for firing in tandem without adverse effects from combustion
gases from upstream burners.
3. Design firing rate for the burners shall be 40,000 / 60,000 / 80,000 / 100, 000 / 120,000 BTU/HR.
4. The design of the burners supplied shall provide for maintaining a constant proportion of fuel gas to
filtered combustion air. These conditions are met for burners in which the pressure of both the fuel
gas and the combustion air are both introduced at zero (atmospheric) pressure and the flow of each
is established by a vacuum on the downstream side of the flow metering orifices.
5. Outside Air: When specified, the system shall be capable of supplying air from outside to each
burner and end vent for the support of combustion in contaminated environments.
C. BURNER CONTROL
1. All burners shall be factory wired for 110 volts with transformer for 24 volt DSI operation as supplied
with a grounded 18” three wire pigtail located at rear of burner.
2. To assure a high degree of fail-safe operation, the design shall preclude main flow of gas if any or
all of the following abnormal conditions occur:
(a.) Main valve fails in open position
(b.) Vacuum pump motor fails (vacuum proving switch cuts power to burners.)
(c.) Power fails (gas valves in burners close in safe position.)
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3. All gas vacuum-firing burner units shall be equipped with a Direct Spark Ignition Module (DSI).
The DSI module shall have a 15 second flame response time before lockout occurs. The spark
shall shut off when the burner flame is established.
4. All units to be supplied with outside air for combustion and any excess air required by system
if inside air contains contaminants.
D. RADIANT PIPING - HEAT EXCHANGER
1. Provide Aluminized pipe throughout system. Minimum heat exchanger surface to be 75 sq. ft
for each 100,000 BTU/HR input. Connections to be made between pipe sections using stainless
steel coupling assemblies.
2. Hanging materials: All system pipe must be supported in accordance with acceptable practices,
local codes, seismic requirements, applicable standards and as shown on plans. Pipe shall pitch
down at least 1” in 20’ toward vacuum pump.
E. REFLECTORS:
1. All reflectors shall be deep dish of a highly infrared reflective material such as aluminum.
2. Standard reflector shall be installed on all radiant pipe, manifold pipe, and tail pipe as
indicated on system layout furnished.
3. System to have perimeter side extension reflector in certain areas of layout as shown on plan
when specified. Side reflector permanently attaches to side of top reflector and is secured to
the pipe by three side reflector supports and two “Z” clips for each 8 ft section of side reflector.
F. END VENT ASSEMBLY:
1. Each open end combustion chamber shall have an approved end vent and the reflector in this area
shall have an end cap, and be installed according to manufacturer’s installation instructions and
as shown on plans.
G. VACUUM PUMP:
1. The system shall vent all products of combustion outdoors by means of the vacuum pump.
2. Vacuum pump shall be equipped with a maximum of 3/4 HP, 60 Hertz, 120 Volt, 3450 RPM,
single phase T.E.F.C. motor. This motor shall have thermal overload protection, ball bearings,
and shall be constructed in accordance with electric motor industry standards.
3. The scroll of this pump shall be cast iron with a minimum metal thickness of approximately
3/16 inch. The impeller wheel shall be cast 319 alloy aluminum with a minimum metal
thickness of approximately 3/32 inch.
4. There will be a low voltage two-wire circuit from the vacuum proving switch (located at
the inlet to the vacuum pump) to the control panel.
5. The connection between the pump inlet and tail pipe is made with an acoustic boot and clamps
provided. The discharge connection is made with a 4.5 inch acoustic boot and 4” porcelain
coated tail pipe.
6. To further assure a high degree of safety, the system will be under negative pressure at all times
during operation to preclude the possibility of the escape of combustion gases inside the building.
7. Vacuum pump motor requires a 1 wire grounded circuit 115 volts, single phase, 60 hertz for a total
of 10 full load amps. This motor must have the same rotation to match the direction of the arrow
on the fan scroll. If the motor is not rotating in this direction, it must be reversed by interchanging
the red wire #8 with the orange wire #5. These are located behind the motor escutcheon plate.
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8. The vacuum pump shall be acoustically isolated from the system with a flexible connector with
a temperature rating of 350oF minimum. The motor in the vacuum pump shall be secured
with rubber mounts for acoustical isolation.
9. Venting materials shall be steel, stainless steel, cast iron, transite pipe or suitable material
as required by local codes and as shown on drawings. Venting materials to be supplied by
the Mechanical Contractor and not by the manufacturer of the equipment.
H. CONTROL PANEL:
1. A pre-wired solid state system control panel shall be provided by the system manufacturer as
shown on drawings for each vacuum pump. The control panel shall provide all relays, controls,
terminals, lights, etc. to control up to four temperature zones with individual thermostats.
Controls shall include a pre-purge sequence of at least 20 seconds prior to initiation of firing
and post-purge sequence of at least 20 seconds after shutdown of the last burner. An interlock
shall be provided to insure that no burner may be fired without the vacuum pump operating,
indicator lights shall appear on outside of panel cover to show Vacuum Pump Operation,
Power On and Zone On.
2. Install electrical wiring as indicated. Connect power wiring to burners and vacuum pumps.
Connect control wiring between vacuum pumps, control panels and thermostats in accordance
with manufacturer’s wiring diagrams. Disconnect switches, if required, to be provided and
installed under Electrical Section (Division 16000).
I. THERMOSTATS:
1. Provide, where indicated, low voltage thermostat connected to control system. Mount
thermostat(s) 48” above finished floor, if not otherwise indicated. Supply number of thermostats as
shown on drawing.
2.3 SYSTEM CONTROLS
A. Pre-wired system control circuits shall be supplied in a control panel with each vacuum pump.
The control panel for the control of the burners shall provide relays & terminals to accommodate
up to four temperature zones with a thermostat and associated control circuits for the burners
for each temperature zone. The control panel shall have indicator lights showing Power On,
Vacuum Pump On and 4-Zones in Operation.
B. All control circuits must be properly polarized. All burner units located on one radiant pipe
line must be on the same zone. All burner units using the same tail pipe also must be on the
same zone (except last 10’ into pump).
C. All combustion chamber and heat exchanger pipes connected to vacuum pump shall be prepurged with air for a period of at least 20 seconds (10 air changes minimum) prior to initiation
of firing sequence.
D. All combustion chamber and heat exchanger pipes connected to a vacuum pump shall be postpurged with air for a period of at least 20 seconds (10 air changes minimum) after shut down
of the last burner firing into the vacuum pump.
E. All vacuum pumps shall be provided with vacuum proving switches to prevent opening of gas
valves until vacuum in the pipe is proven.
F. Pre-purge of the system is obtained from the solid state timer relay located in the furnished panel.
The first zone thermostat calling for heat will activate this relay. The pump motor will start and
the vacuum proving switch, after sensing a minus pressure of 2” water column, completes the
circuit to begin pre-purge. After approximately 45 seconds, the 110 volt control circuits will be
activated and burners will light automatically. The burners will remain on until the thermostat is
satisfied. At that time, the gas valve and DSI will drop out, but the pump will continue to run to
give a post-purge. This post-purge period on the last zone thermostat to be satisfied (internally
provided in panel box).
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G. The low voltage control system furnished is designed to maintain the set point of the thermostat
without additional controls added in the field. Night set-back of this system is not recommended.
The system must not be turned off at night or on weekends. (Night set-back of not over 10 degrees
may be used on weekends or extended periods of time when the building is not occupied.) Any
automatic night set-back devise would have to be installed outside the control panel and on the low
voltage circuit only to avoid violating AGA certification.
H. The system wiring diagram shall conform to wiring diagrams furnished with installation and
service sheets furnished with the units and as on plans.
I.
All thermostats are low voltage bimetal action with heat anticipator. Low voltage thermostats
shall be numbered instead of marked in degrees and shall not have thermometers. Low voltage
fittings must follow local codes.
PART 3 – EXECUTION
3.1 INSTALLATON
A. Install radiant heaters as noted in Section 2.2D
B. Install and connect gas-fired radiant heaters and associated fuel and vent features and systems
according to NFPA 54, applicable local codes and regulations, and manufacturer’s written installation
instructions.
C. Suspended Units: Suspend from substrate using chain hangar kits and building attachments.
3.2 CONNECTIONS
A. Gas supply piping must meet local codes and fuel supplier requirements and be sized in accordance
with BTU demand, available pressure, and the total equivalent length of pipe required (fittings
included).
B. Connection from gas supply line to burner unit must be made in accordance with installation
details on plans. Special connections are used to allow for expansion and contraction of radiant piping.
C. Gas shut-off cock, as supplied with unit, and controls in unit must not be subjected to more than 1/2#
or 14 inches water column (W.C.) pressure. If high pressure testing of gas supply line is required, this
test must be made with a plug in the 1/2 inch branch line to each burner. Never test the gas line with
the 1/2 inch IPS x 3/4” SAB shut-off cock installed or with the burner unit connected.
D. Electrical wiring must conform to National Electric Code and local ordinances in accordance with
diagrams furnished.
1. Provide outlet box with 3-wire grounded receptacle within 12 inches of each burner or wire as per
local code requirements. Units supplied with 24” cord to plug into 3-wire grounded receptacle.
However, if another means of disconnect is required by local codes, it will be the responsibility of
the electrical or temperature control contractor to provide and wire the same.
3.3 FIELD QUALITY CONTROL
A. Provide start-up, test and adjust gas fired radiant heaters in accordance with manufacturer’s start-up
instructions and utility company’s requirements. Check and calibrate controls, adjust burners for
maximum efficiency.
3.4 ADJUSTING
A. Check and calibrate controls, adjust burners for maximum efficiency
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3.5 DEMONSTRATION
A. Provide services of manufacturer’s technical representative for one half day to instruct owner’s personnel
in operation and maintenance of gas fired radiant heaters. Schedule training with Owner, provide at
least seven day notice to Contractor and Engineer of training date.
END OF SECTION 15542
2015 Co-Ray-Vac Radiant Heating System – Base Bid Specs
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