SYSTEM LOCKOUT AND DIAGNOSTIC FEATURES
SYSTEM LOCKOUT FEATURES
When system lockout occurs, the gas valve is de-energized. The circulator blower may be energized at heat speed for some faults, and if flame is sensed, the inducer blower is energized. The diagnostic indicator light will flash or glow continuously to indicate system status. (System lockout will never override the precautionary features.)
To reset the control after system lockout, do one of the following:
1.Interrupt the call for heat at the thermostat for at least one second, but for less than 20 seconds (if flame is sensed with the gas valve de-energized, interrupting the call for heat at the thermostat will not reset the control).
2.Interrupt the 24 VAC power at the control for at least ten seconds. You may also need to reset the flame rollout sensor switch.
3.After one hour in lockout, the control will automatically reset itself.
DIAGNOSTIC FEATURES
The 50A66-743 control continuously monitors its own operation and the operation of the system. If a failure oc- curs, the DS 1 (red) and DS 2 (green) LEDs will indicate a failure code as shown below.
