8
The rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped to
operate on the type of gas available. Conversion to LP gas
is permitted with the use of a factory authorized conversion
kit. Contact your distributor or refer to the specification
sheet for your model for a listing of approved LP gas con-
version kit(s). Refer to the Installation Manual provided with
the LP kit for conversion from natural gas to propane gas.
The minimum supply pressure should not vary from that
shown in the Inlet Gas Pressure table because this could
prevent the unit from having dependable ignition. In addi-
tion, gas input to the burners must not exceed the rated
input shown on the rating plate. Overfiring of the unit could
result in premature heat exchanger failure.
Natural
Min. 5.0" W.C., Max. 10.0" W.C.
Propane
Min. 11.0" W.C., Max. 13.0" W.C.
INLET GAS PRESSURE
Inlet Gas Pressure Must be within the Minimum and Maximum Value
Shown in Table Above.
High Altitude Derate (U.S. Installations Only)
Installation of this furnace at altitudes above 2000 ft (610
m) shall be made in accordance with the Listed High Alti
-
tude Conversion Kit available with this furnace.
IMPORTANT NOTE: The gas/electric units naturally
derate with altitude. Do not attempt to increase
the firing rate by changing orifices or increasing
the manifold pressure. This can cause poor com-
bustion and equipment failure. At all altitudes,
the manifold pressure must be within 0.3 inches
W.C. of that listed on the nameplate for the fuel
used. At all altitudes and with either fuel, the air
temperature rise must be within the range listed
on the unit nameplate. Contact your distributor
or refer to the specification sheet for your model
for listing of approved high altitude conversion
kit(s). Refer to the Installation Manual provided
with the high altitude kit for altitude adjustments.
Use HA03 for installations above 2000’.
NOTE: No changes are required up to 2,000 feet.
Use the appropriate high altitude kit above 2,000
feet.
Piping
IMPORTANT NOTE: To avoid possible unsatisfactory
operation or equipment damage due to under firing
of equipment, do not undersize the natural/propane
gas piping from the meter/tank to the unit. When siz-
ing a trunk line, include all appliances on that line
that could be operated simultaneously.
The rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped to
operate on the type of gas available. The gas line instal-
lation must comply with local codes, or in the absence of
local codes, with the latest edition of the National Fuel Gas
Code NFPA 54/ANSI Z223.1.
Natural Gas Connection
Refer to the Proper Piping Practice drawing for the general
layout at the unit. The following rules apply:
1.
Use black iron pipe and fittings for the supply piping.
The use of a flex connector and/or copper piping is
permitted as long as it is in agreement with local
codes.
2. Use pipe joint compound on male threads only. Pipe
joint compound must be resistant to the action of the
fuel used.
3. Use ground joint unions.
4. Install a drip leg to trap dirt and moisture before it can
enter the gas valve. The drip leg must be a minimum
of three inches long.
5. Use two pipe wrenches when making connection to
the gas valve to keep it from turning.
6.
Install a manual shut-off valve in a convenient location
(within six feet of unit) between the meter and the unit.
7. Tighten all joints securely.
8. The unit must be connected to the building piping by
one of the following methods:
•
Rigid metallic pipe and fittings
•
Semirigid metallic tubing and metallic fittings (Alu
-
minum alloy tubing must not be used in exterior
locations)
• Listed gas appliance connectors used in accor-
dance with the terms of their listing that are com-
pletely in the same room as the equipment
• In the prior two methods above the connector or
tubing must be protected from physical and thermal
damage. Aluminum alloy tubing and connectors
must be coated to protect against external corro-
sion when in contact with masonry, plaster or insu-
lation or are subject to repeated wettings by liquids
(water - not rain water, detergents or sewage).
NOTE: The unit gas supply entrance is factory
sealed with plugs. Keep plugs in place until gas
supply is ready to be installed. Once ready, re-
place the plugs with the supplied grommets and
install gas supply line.
