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GAS SUPPLY AND PIPING
The furnace rating plate includes the approved furnace gas input
rating and gas types. The furnace must be equipped to operate
on the type of gas applied. This includes any conversion kits
required for alternate fuels and/or high altitude.
Inlet gas supply pressures must be maintained within the ranges
specified in the Inlet Gas Supply Pressure chart. The supply
pressure must be constant and available with all other household
gas-fired appliances operating. The minimum gas supply
pressure must be maintained to avoid unreliable ignition. The
maximum must not be exceeded to keep the furnace from
overfiring.
High Altitude Derate
When this furnace is installed at high altitude, the appropriate
high-altitude orifice kit must be applied. This is required due to
the natural reduction in the density of both the gas fuel and
combustion air as altitude increases. The kit will provide the
proper design-certified input rate within the specified altitude
range.
High-altitude kits are purchased according to the installation
altitude and usage of either Natural or propane gas. Contact your
distributor for a tabular listing of appropriate altitude ranges and
corresponding manufacturer’s high-altitude (Natural, propane
gas, and/or pressure switch) kits.
NOTE: Do not derate the furnace by adjusting the manifold
pressure to a lower pressure than specified on the furnace rating
plate. The combination of the lower air density and a lower
manifold pressure will prohibit the burner orifice from drawing the
proper amount of air into the burner. This may cause incomplete
combustion, flashback and possible yellow tipping.
In some areas the gas supplier may artificially derate the gas in
an effort to compensate for the effects of altitude. If the gas is
artificially derated, the appropriate orifice size must be
determined based upon the Btu/ft
3
content of the derated gas
and the altitude. Refer to the National Fuel Gas Code, NFPA 54/
ANSI Z223.1, and information provided by the gas supplier to
determine the proper orifice size.
A different pressure switch may be required at high altitude
regardless of the Btu/ft
3
content of the fuel used. Contact your
distributor for a tabular listing of appropriate altitude ranges and
corresponding manufacturer’s pressure switch kits.
Propane Gas Conversion
This furnace is configured for Natural gas. The appropriate
manufacturer’s propane gas conversion kit, must be applied for
propane gas installations. Refer to “Propane Gas and/or High
Altitude Installations” section for details.
Contact your distributor for a tabular listing of appropriate
manufacturer’s kits for propane gas and/or high altitude
installations. The indicated kits must be used to ensure safe and
proper furnace operation. All conversions must be performed by
a qualified installer or service agency.
Gas Control Valve
This furnace is equipped with a 24-volt gas control valve
controlled during the furnace operation by the integrated control
module. As shipped, the gas control valve is configured for
Natural gas. The gas control valve is field-convertible for use with
propane gas by replacing the regulator spring with a propane gas
spring from an appropriate manufacturer’s propane gas
conversion kit. Taps for measuring the gas supply pressure and
manifold pressure are provided on the valve.
The gas control valve has a manual On/Off control located on the
gas control valve itself. This control may be set only to the On or
Off position.
Refer to the lighting instructions label or see “Start-Up Procedure
and Adjustment” for use of this control during the start-up and
shutdown periods.
Gas Piping Connections
When sizing a trunk line, be sure to include all appliances which
will operate simultaneously when sizing a trunk line.
Inlet Gas Supply Pressure
Natural gas
5.0" W.C. minimum; 10.0" W.C. maximum
Propane gas
11.0" W.C. minimum; 13.0" W.C. maximum
Goodman 61
To prevent unreliable operation or equipment damage,
the inlet gas supply pressure must be as specified on the
unit rating plate with all other household gas-fired
appliances operating.
CAUTION
Goodman 52
Possible property damage, personal injury or death may
occur if the correct conversion kits are not installed. The
appropriate kits must be applied to ensure safe and proper
furnace operation. All conversions must be performed by
a qualified installer or service agency.
WARNING
Goodman 62
To avoid possible unsatisfactory operation or equipment
damage due to underfiring of equipment, use the proper
size of Natural/propane gas piping needed when running
pipe from the meter/tank to the furnace.
CAUTION
