Service Manual

Sequence of Operation

Lockout Conditions

The system will go into lock out mode for the following reasons:

1. Error Code 110 (Ignition failure occurred)

a. Control board will go into “Soft Lockout” if the main burner cannot be lit or fails to prove flame

after 3 ignition trials. The water heater display indicates a lockout condition by showing an error

code number 110 with “Service Needed” in the control display window. Refer to error codes in

the diagnostic section of this Service Manual. In a Soft Lockout condition, the control will wait for

15 minutes and then make 3 more attempts to light the main burners. Soft lockout reset is

accomplished by depressing the lower right button under “Reset” for 3 seconds.

2. Error Code 80 (High limit overheat condition)

a. If the top of the tank should exceed 207°F (92.7°C), then the high limit control will shut off the

burner and the water heater will go into a “Hard Lockout.” Error code 80 will be shown in the

water heater display. The control can only be reset in the Service Mode, which is detailed in the

Troubleshooting section (page 13).

3. Error Code 67 (ILK off)

a. If the vent safety switch located on the draft hood should open, the gas valve will close, the

blower will post-purge and error code 67 will appear on the display. The lockout condition will

reset once the problem is corrected and the switch reset. Refer to Vent Safety Switch Testing

and Replacement.

Connection/Wiring Diagram