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PRESSURE SWITCH FOR WATER HEATER
1. Follow water heater manufacturer’s instructions to light pilot. Turn the gas control valve to the ON position.
Then adjust the thermostat to call for heat, which will energize the venter motor. (May see a 1 to 8 sec.
delay of venter motor)
2. Turn gas control valve to the PILOT position, which will start a 1 to 3 min. post purge of the venter motor.
3. Repeat Step 1 and 2 to ensure proper operation.
SPILLAGE SWITCHES
1. Allow the water heater to heat up to operating temperature, then disconnect the power to the gas pressure
switch.
2. Adjust the thermostat to call for heat with the venter inoperative. Allow approximately 2 minutes of fl ue gas
spillage for the spillage switches to sense the spillage and disrupt the thermocouple circuit, halting the gas
fl ow to the pilot and burner.
3. Wait 2 to 3 minutes. Reset the spillage switches and light the pilot, then perform a second safety spillage
test (Steps 1 and 2).
CAUTION: If for any reason the system has shut down during operation, the cause of the system failure should
be investigated and corrected before resetting the safety switch and restarting the system.
P/N 46285300 Rev F 01/18
SYSTEM CONTROL CHECK OUT PROCEDURES
For furnaces or boilers, adjust the thermostat to call for heat and observe the power venting system for proper
operation sequence. (Repeat if necessary)
1. Thermostat calls for heat.
a. Relay is energized and venter motor starts.
b. Pressure switch closes and burner starts.
c. Thermostat is satisfi ed, the burner stops.
d. This starts the post purge cycle. Purge time 1 to 2 min.
e. While system is operating, disconnect power to the venter motor. This should open the pressure switch
contacts and stop burner operation.
Diagram C
