Goodman Amana AMH8 Service Instructions Manual page 58

SERVICING
GAS LINE
GAS SHUTOFF VALVE
DRIP LEG CAP
WITH FITTING
MANOMETER HOSE
Measuring Inlet Gas Pressure
(Alternate Method)
3. Turn ON the gas and electrical power supply and
operate the furnace and all other gas consuming
appliances on the same gas supply line.
4. Measure furnace gas supply pressure with burners
firing. Supply pressure must be within the range
specified in the following table.
INLET GAS SUPPLY PRESSURE
Natural Gas Minimum: 4.5" w.c.
Propane Gas Minimum: 11.0" w.c.
If supply pressure differs from above, make necessary
adjustments to pressure regulator, gas piping size, etc.,
and/or consult with local gas utility.
HIGH VOLTAGE
D ALL
ISCONNECT ELECTRICAL POWER AND SHUT OFF GAS
SUPPLY BEFORE SERVICING OR INSTALLING THIS UNIT.
M
ULTIPLE POWER SOURCES MAY BE PRESENT.
DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
5. Disconnect manometer after turning off gas at
manual shutoff valve. Reinstall plug before turning
on gas to furnace.
6. Turn OFF any unnecessary gas appliances started in
step 3.
7. Turn on gas to furnace and check for leaks. If leaks
are found, repair and then reinstall burner compart-
ment door.
8. Turn on electrical power and verify proper unit op-
eration.
58
GAS LINE
TO FURNACE
OPEN TO
ATMOSPHERE
MANOMETER
Maximum: 10.0" w.c.
Maximum: 13.0" w.c.
WARNING
F
AILURE TO
HIGH VOLTAGE
D ALL
ISCONNECT ELECTRICAL POWER AND SHUT OFF GAS
SUPPLY BEFORE SERVICING OR INSTALLING THIS UNIT.
M
ULTIPLE POWER SOURCES MAY BE PRESENT.
DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
Gas Manifold Pressure Measurement and Adjust-
ment
Natural Gas Adjustments
To test & set low fire manifold gas pressure on the H
model furnace it is recommended that dip switch #2 be
set to the "Two Stage" position and dip switch #3 be
set to 5 minute delay. Operating sequence will be; high
fire ignition, after several seconds the burner input will
go to low fire for a 5 minute period. Low fire can be set
during this time. To check & set high fire it is recom-
mended that dip switch #2 be set to single stage for the
test period.
HIGH VOLTAGE
D ALL
ISCONNECT ELECTRICAL POWER AND SHUT OFF GAS SUPPLY
BEFORE SERVICING OR INSTALLING.
NOTE: Use adapter kit #0151K00000S to measure gas
pressure on White-Rodgers 36G54 gas valves.
Only small variations in gas pressure should be made by
adjusting the gas valve pressure regulator. The mani-
fold pressure must be measured with the burners oper-
ating. To measure and adjust the manifold pressure,
use the following procedure.
1. After turning off gas to furnace at the manual gas
shutoff valve external to the furnace, remove burner
compartment door to gain access to the gas valve.
2. Connect a calibrated water manometer (or appro-
priate gas pressure gauge) at the gas valve outlet
pressure tap. Refer to Measuring Gas Pressure: Two-
Stage Valves figure for two-stage gas valve outlet
pressure tap connections.
WARNING
L
INE VOLTAGE NOW PRESENT
3. White-Rodgers 36G54 Valves:
a. Back outlet pressure test screw ( out one turn
(counterclockwise, not more than one turn).
b. Attach a hose and manometer to the outlet pres-
sure.
WARNING
F
AILURE TO
WARNING