Service Manual

ManualsBrandsGOODMAN ManualsForced Air Furnaces96% AFUE 100,000 BTU Multi-Positional 2-Stage Varibale Speed Natural Gas Furnace with 21 in. Cabinet

INSTALLATION CONSIDERATIONS

Inlet gas supply pressures must be maintained within the

ranges specified below. The supply pressure must be con-

stant and available with all other household gas fired appli-

ances operating. The minimum gas supply pressure must

be maintained to prevent unreliable ignition. The maximum

must not be exceeded to prevent unit overfiring.

Natural Gas Minimum: 4.5" w.c. Maximum: 10.0" w.c.

Propane Gas Minimum: 11.0" w.c. Maximum: 13.0" w.c.

INLET GAS SUPPLY PRESSURE

HIGH ALTITUDE DERATE

When this furnace is installed at high altitude, the appropri-

ate 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 speci-

fied altitude range.

High altitude kits are purchased according to the installa-

tion altitude and usage of either natural or propane gas.

Refer to the product Specification Sheet or Technical Manual

for a tabular listing of appropriate altitude ranges and corre-

sponding manufacturer’s high altitude (Natural, Propane gas,

and/or Pressure Switch) kits.

Do not derate the furnace by adjusting the manifold pres-

sure to a lower pressure than specified on the furnace rat-

ing 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 yel-

low 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

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

content of the fuel used. Refer to

the product Specification Sheet or Technical Manual for a

tabular listing of appropriate altitude ranges and correspond-

ing manufacturer’s pressure switch kits.

PROPANE GAS CONVERSION

WARNING

OSSIBLE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH MAY OCCUR IF

THE CORRECT CONVERSION KITS ARE NOT INSTALLED.

HE APPROPRIATE KITS

MUST BE APPLIED TO INSURE SAFE AND PROPER FURNACE OPERATION.

CONVERSIONS MUST BE PERFORMED BY A QUALIFIED INSTALLER OR SERVICE

AGENCY.

MANIFOLD

DESCRIPTION: This kit is designed for gas-fired units con-

verted to propane gas use. The Propane Low Pressure

(LPLP03) Kit monitors the gas line pressure with a pressure

switch and disables the unit's gas valve if the line pressure

drops below acceptable levels.

GAS VALVE

This unit is equipped with a 24 volt gas valve controlled dur-

ing furnace operation by the integrated control module. As

shipped, the valve is configured for natural gas. The valve is

field convertible for use with propane gas by using the ap-

propriate propane gas conversion kit. Taps for measuring

the gas supply pressure and manifold pressure are provided

on the valve.

Low (Main)

Common

High

White-Rodgers 2-Stage Valve

NOTE: The gas supply pressure on White-Rodger "J"

model gas valve, used on single and two stage fur-

naces, can be checked with a gas pressure test kit (Part

#0151K00000S) available through our authorized dis-

tributors.