14
Secondary
Control Limit
Back of Unit
Secondary Limit Control
Pre-Operation Checks
1. Close the manual gas valve external to the unit.
2.
Turn off the electrical power supply to the unit.
3. Set the room thermostat to its lowest possible setting.
4. Remove the heat exchanger door on the side of the
unit by removing screws.
5. This unit is equipped with an ignition device which
automatically lights the main burner. DO NOT try to
light burner by any other method.
6. Move the gas control valve switch to the OFF position.
Do not force.
7.
Wait five minutes to clear out any gas.
8. Smell for gas, including near the ground. This is
important because some types of gas are heavier
than air. If you have waited five minutes and you do
smell gas, immediately follow the warnings near the
beginning of this manual. If having waited for five
minutes and no gas smell is noted, move the gas
control valve switch to the ON position.
9. Replace the heat exchanger door on the side of the
unit.
10. Open the manual gas valve external to the unit.
11. Turn on the electrical power supply to the unit.
12. Set the thermostat to desired setting.
Gas Supply And Manifold Check
Gas supply pressure and manifold pressure with the
burners operating must be as specified on the rating plate.
Gas Supply Pressure Measurement
NOTE: Use adapter kit #0151K00000S to measure
gas pressure on White-Rodgers 36J22Y gas valves.
CAUTION
To prevent unreliable operation or equipment damage, the
inlet 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 Inlet Gas Supply Pressure range specified. The supply
pressure can be measured at the gas valve inlet pressure
tap or at a hose fitting installed in the gas piping drip leg.
The supply pressure must be measured with the unit OFF.
To measure inlet pressure, use the following procedure.
White-Rodgers Model 36J22Y-204
1.
Turn OFF gas to furnace at the manual gas shutoff
valve external to the furnace.
2. Turn OFF all electrical power to the system.
3. Inlet pressure tap connections:
a. White-Rodgers Valve:
Back inlet pressure test screw (inlet pressure tap
out one turn (counterclockwise, not more than one
turn).
2. Connect manometer (or appropriate pressure gauge)
at either the gas valve inlet pressure tap or the gas
piping drip leg. See White-Rodgers 36J22Y-204 gas
valve for location of inlet pressure tap.
3. Turn ON the gas supply.
4. Turn On power and operate the furnace and all other
gas consuming appliances on the same gas supply
line.
5. Using a leak detection solution or soap suds, check for
leaks at screw (White-Rodgers valve). Bubbles forming
indicate a leak. SHUT OFF GAS AND REPAIR ALL
LEAKS IMMEDIATELY!
6.
Measure the gas supply pressure with burners firing.
Adjust supply pressure using the
Inlet Gas Supply
Pressure
table shown below. If supply pressure
reading differs from the table, make necessary
adjustments to pressure regulator, gas piping size,
etc., and/or consult with local gas utility.
Natural Gas
Min. 5.0" W.C., Max. 10.0" W.C.
INLET GAS SUPPLY PRESSURE
7. Turn OFF all electrical power and gas supply to the
system.
