WATER HEATER OPERATION
The figure below shows the water heater’s sequence of operation when a call for heat is initiated. The gas control valve/thermostat will attempt to light the burner three times. If the flame sense rod in the burner/ manifold assembly does not detect ignition, the control will enter lockout mode indicated by the electronic control display’s flashing of the appropriate status code.
SEQUENCE OF OPERATION
Call for heat indicated by flashing of display screen status codes.
Gas valve/thermostat will do a relay check (relay clicks will be heard).
Display will show temperature set point during call for heat.
Draft Blower is energized.
System will verify pressure switch operation and start a 5 second
Ignitor will start a 12 second warm up period. “IGN” will show on display.
Gas valve/thermostat will open for 4 second trial for ignition and fan will turn on.
Main burner flame is detected by flame sense rod. Air intake fan and main burner will continue to operate until water temperature inside the tank reaches temperature set point.
Gas valve/thermostat is de- energized and air intake fan continues for a post purge time of approximately 5 seconds.
Water heater returns to standby mode.
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