Amana Gas Furnaces: GUC, GUD, GUI, GUX Re: Lockout Codes The original control module in these furnaces is a White-Rodgers 50A50 controller. 50A50-206 Integrated Furnace Control Code Description On Replace control 1 Lockout due to failed ignition 2 ...

Amana Gas Furnace: GUC/GUX Re: Locking-Out / Sometime Doesn't Heat The customer reports that the furnace sometimes does not heat, and that they are able to get the furnace to restart by turning the thermostat off and back on or by cycling power to the furnace. These furnaces use a...

Amana Gas Furnace; GUC/GUX Re: Flashing Code 1 If a flame was not sensed during the first 7 seconds after the gas valve was energized, the control turns off the gas. The control will make 3 tries before it determines that it cannot establish measureable combustion and enters a lockout...

Amana Gas Furnace: GUC/GUX Re: Flashing Code 2 Code 2 = Pressure switch stuck closed The furnace pressure switch should only close when the inducer fan output is energized. If control board is not energizing the inducer fan output and the switch is closed, the board will flash a code 2. ►...

Amana Gas Furnace: GUC/GUX Re: Flashing Code 3 (Assuming original control board) If, after the vent blower is energized, the pressure switch does not close, the control will keep the blower on and wait for the switch to close. The diagnostic code for this problem is 3 short flashes followed...

Amana Gas Furnace: GUC/GUX Re: Flashing Code 4 (Assuming original control board) If the limit control opens, the burners will be de-energized and the air circulation and vent blower will be turned on until the limit closes. The diagnostic light code for this is four short flashes followed by...