Gas Supply Pressure Measurement - Goodman GCH95 Installation Instructions Manual

F S
URNACE HUTDOWN
1. Set the thermostat to the lowest setting. The integrated
control will close the gas valve and extinguish flame.
Following a 15 second delay, the induced draft blower will
be de-energized. After a 100 or 150 second delay period
(field selectable), the circulator blower will be de-energized.
2. Remove the burner compartment door and move the furnace
gas valve manual control to the OFF position.
3. Close the manual gas shutoff valve external to the furnace.
4. Replace the burner compartment door.
G S P M
AS UPPLY RESSURE
T
O PREVENT UNRELIABLE OPERATION OR EQUIPMENT DAMAGE
I
NLET GAS SUPPLY PRESSURE MUST BE AS SPECIFIED ON THE UNIT
RATING PLATE WITH ALL OTHER HOUSEHOLD GAS FIRED APPLIANCES
.
OPERATING
The line pressure supplied to the gas valve must be within the
range specified below. The supply pressure can be measured at
the gas valve inlet pressure boss or at a hose fitting installed in the
gas piping drip leg. The supply pressure must be measured with
the burners operating. To measure the gas supply pressure, use
the following procedure.
INLET
Gas Valve On/Off
Selector Switch
White-Rodgers Model 36G54 (Two-Stage)
Open to
Atmosphere
Outlet
Pressure Boss
Inlet
Pressure
Boss
White-Rodgers Model 36G54 Connected to Manometer
EASUREMENT
CAUTION
OUTLET
High Fire Regulator
Adjust
Regulator
Common
Terminal(C)
Gas Valve On/Off
Selector Switch
,
THE
i
Outlet Pressure Tap
1/8 NPT
Honeywell Model VR9205 Connected to Manometer
1. Turn OFF gas to furnace at the manual gas shutoff valve
external to the furnace.
2. Connect a calibrated water manometer (or appropriate gas
pressure gauge) at either the gas valve inlet pressure boss
or the gas piping drip leg. See Honeywell VR9205 gas valve
figure or White-Rodgers 36G54 gas valve figure for location
of inlet pressure boss.
NOTE: If measuring gas pressure at the drip leg or Honeywell
Vent VR9205 gas valve, a field-supplied hose barb fitting must be installed
prior to making the hose connection. If using the inlet pressure
boss on the White-Rodgers 36G54 gas valve, then use the 36G
Valve Pressure Check Kit, Goodman Part No. 0151K00000S.
3. Turn ON the gas supply and operate the furnace and all
other gas consuming appliances on the same gas supply
Low Fire
line.
Regulator
Adjust
4. Measure furnace gas supply pressure with burners firing.
Supply pressure must be within the range specified in the
Inlet Gas Supply Pressure table.
Natural Gas
Propane Gas Minimum: 11.0" w.c.
31
Regulator
Vent
Inlet Gas Supply Pressure
Minimum: 5.0" w.c. Maximum:10.0" w.c.
Maximum:13.0" w.c.
High Fire
Regulator
Adjust
Low Fire
Regulator
Adjust
Common
Terminal(C)
High Fire Coil
Terminal (HI)
Low Fire Coil
Terminal (LO)
Inlet Pressure Tap
1/8 NPT