34
WARNING
HIGH VOLTAGE
Disconnect ALL power before servicing or in
-
stalling this unit. Multiple power sources may
be present. Failure to do so may cause proper
-
ty 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
compartment door.
8. Turn on electrical power and verify proper unit
operation.
WARNING
HIGH VOLTAGE
Disconnect ALL electrical power and shut off
gas supply before servicing or installing this
unit. Multiple power sources may be present.
Failure to do so may cause property damage,
personal injury or death.
GAS MANIFOLD PRESSURE
MEASUREMENT AND ADJUSTMENT
CAUTION
To prevent unreliable operation or equipment damage, the
gas manifold pressure must be as a specified on the unit
rating plate. Only minor adjustments should be made by
adjusting the gas valve pressure regulator.
NOTE: Use adapter kit #0151K00000S to measure
gas pressure on White-Rodgers 36J22 gas valves.
Only small variations in gas pressure should be made by
adjusting the gas valve pressure regulator. The manifold
pressure must be measured with the burners operating.
To measure and adjust the manifold pressure, use the
following procedure.
WARNING
HIGH VOLTAGE
Disconnect ALL electrical power and shut off gas supply
before servicing or installing.
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 appropriate
gas pressure gauge) at the gas valve outlet pressure
tap. Refer to Measuring Gas Pressure: Single Stage
Valves figure for single stage valve outlet pressure tap
connections.
WARNING
Line Voltage now present.
3. Turn ON the gas and electrical power supply and
operate the furnace.
4. Measure gas manifold pressure with burners firing.
Adjust manifold pressure using the table below.
Natural Gas
3.5" w.c.
Propane Gas
10.0" w.c.
Manifold Gas Pressure
The final manifold pressure must not vary more than ± 0.3“
w.c. from the above specified pressures. Any necessary
major changes in gas flow rate should be made by
changing the size of the burner orifice.
5. White-Rodgers 36J22 Valves:
a. Back outlet pressure test screw (inlet/outlet
pressure boss) out one turn (counterclockwise,
not more than one turn).
b. Attach a hose and manometer to the outlet
pressure outlet pressure boss.
c. Turn ON the gas supply.
d. Turn on power and close thermostat “R” and “W1”
contacts to provide a call for heat.
e. Measure the gas manifold pressure with burners
firing. Adjust manifold pressure using the Manifold
Gas Pressure table shown below.
f. Remove regulator cover screw from the
outlet pressure regulator adjust tower and
turn screw clockwise to increase pressure or
counterclockwise to decrease pressure. Replace
regulator cover screw.
g. Turn off all electrical power and gas supply to the
system.
h. Remove the manometer hose from the hose barb
fitting or outlet pressure boss.
i. Turn outlet pressure test screw in to seal pressure
port (clockwise, 7 in-lb minimum).
6. Honeywell VR8215 Valve:
a. Remove the outlet pressure boss plug. Install an
1/8” NPT hose barb fitting into the outlet pressure
tap.
b. Attach a hose and manometer to the outlet
pressure barb fitting.
c. Turn ON the gas supply.
d. Turn on power and close thermostat “R” and “W1”
contacts to provide a call for low stage heat.
e. Measure the gas manifold pressure with burners
firing. Adjust manifold pressure using the Manifold
Gas Pressure table shown below.
SERVICING