York Gas Furnace: PMPD/PDPD

Re: Flashing Code 5

Flashing Code 5 = Rollout Switch Open

There are up to three manual-reset rollout limits mounted around the burners.

Other symptoms associated with a Code 5:

• Blower and Inducer Running Continuous
• No Heat

CHECKOUT:

1. Check Rollout Switches

• Reset the furnace by cycling power.
• Start a call for heat by energizing "W".
• Monitor the LED on the furnace board for a lockout indication.
  • If the board immediately goes into a Code 5, press the reset button on each Rollout limit and retry.
    • Code 5 Goes Away ⇒ Check for a Bad Heat Exchanger
    • Still Code 5 → Step 2. Check Control Board

2. Check Control Board

• At the control board 12-pin plug:
  • Check for 24VAC between Pin# 11 (BRN) and "C".
  • Check for 24VAC between Pin# 5 (BLK) and "C".
    • Power at Both Pins + Code 5 = Bad Control Board
    • Power on One Pin Only = Open Limit Circuit ⇒ Turn off power to the furnace & check resistance across each roll-out switch.
      • No Resistance + Won't Reset by Button Press = Bad Rollout Limit