Gas Manifold Pressure Measurement And Adjustment - Whirlpool WGFM195 Installation Instructions Manual

Gas Control Valve—Honeywell VR9205 2-Stage
A. Regulator vent
B. High-fire regulator adjust
Gas Control Valve—Honeywell VR9205 Connected to
Manometer
B
A
i
H
A. Open to atmosphere
B. Manometer hose
C. Common terminal (C)
D. High-fire coil terminal (HI)
1. Turn off the 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 control valve inlet pressure
boss or the gas piping drip leg. See Gas Control Valve—
Honeywell VR9205 Connected to Manometer or Gas Control
Valve—White-Rodgers 36G54 Connected to Manometer for
location of inlet pressure boss/tap.
NOTE: If measuring the gas pressure at the drip leg or on the
Honeywell VR9205 gas control 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
control valve, then use the 36G Valve Pressure Check Kit, Part
Number 0151K00000S.
3. Turn on the gas supply and operate the furnace and all other
gas consuming appliances on the same gas supply line.
4. Measure the furnace gas supply pressure with burners firing.
NOTE: Supply pressure must be within the range specified in the
Inlet Gas Supply Pressure chart.
Inlet Gas Supply Pressure
Natural Gas Minimum: 5.0" W.C.Maximum: 10.0" W.C.
Propane Gas Minimum: 11.0" W.C.Maximum: 13.0" W.C.
34
A
B
C
D
C. Low-fire regulator adjust
D. On/Off selector switch
C
D
E
F
G
E. Low-fire coil terminal (LO)
F. ¹⁄₈ " NPT inlet pressure tap
G. ¹⁄₈ " NPT outlet pressure tap
H. Manometer
If the supply pressure differs from chart, make the necessary
adjustments to the pressure regulator, gas piping size, etc., and/
or consult with local gas utility.
5. Turn off the gas supply to the furnace at the manual shutoff
valve.
6. Disconnect the manometer.
7. Reinstall plug before turning on gas supply to furnace.
8. Turn off any unnecessary gas appliances started in Step 3.
Measuring Inlet Gas Pressure Alternate Method
A
B
G
A. Gas supply line
B. Gas shutoff valve
C. Gas supply line to furnace
D. Open to atmosphere
Gas Manifold Pressure Measurement and
Adjustment
CAUTION
To prevent unreliable operation or equipment damage,
the gas manifold pressure must be as specified on the
unit rating plate. Only minor adjustments should be made
by adjusting the gas control valve pressure regulator.
Only small variations in gas pressure should be made by
adjusting the gas control valve pressure regulator. The manifold
pressure must be measured with the burners operating. To
measure and adjust the manifold pressure, use the following
procedure.
1. Turn off the gas supply to furnace at the manual gas shutoff
valve external to the furnace.
2. Turn off all electrical power to the system.
3. Outlet pressure tap connections:
Honeywell VR9205 valve: Remove the outlet pressure
boss plug. Install an ¹⁄₈" NPT hose barb fitting into the
outlet pressure tap.
White-Rodgers 36G54 valve: Back outlet pressure test
screw (inlet/outlet pressure boss) out one turn
(counterclockwise, not more than one turn).
4. Attach a hose and manometer to the outlet pressure barb
fitting (Honeywell valve) or outlet pressure boss
(White-Rodgers valve).
5. Turn on the gas supply.
6. Turn on power and close thermostat R and W1 contacts to
provide a call for low-stage heat.
7. Measure the gas manifold pressure with burners firing.
C
D
F
E
E. Manometer
F. Manometer hose
G. Drip leg cap with fitting