York Gas Furnaces: P1XU Re: Lockout Codes This York gas furnace has a control board inside the furnace blower compartment that will flash a diagnostic code that shows the operating status of the furnace. Diagnostic Codes: ON Replace Control 2 Red Pressure switch...

York Gas Furnace: P1XU Re: Flashing Code 3 Code 3 = One or More Pressure Switch(es) Open with the Inducer Energized. The P1XU gas furnace has a 2-stage gas valve and 2-speed inducer fan motor. There are two, Dual-Port Pressure Switches which monitor both low and high speed operation of the...

York Gas Furnace: P1XU Re: Flashing Code 6 The P1XUD gas furnace has a 2-stage gas valve and 2-speed inducer fan motor. There are two, dual-port pressure switches which monitor both low and high speed operation of the inducer motor. The low pressure port of the switches goes to the inducer...

York Gas Furnace: P1XU Re: No Heat - Flashing Code 7 (Assuming original control board) Code 7 = Failure to Sense Flame Qty Possible Causes: Dirty Flame Sensor 1 Bad Glow Plug 1 Clogged Burners Intake Problem No or Low Gas Pressure ...