Carrier Gas Furnace: 58MXA

Re: Flashing Code 13 / Fault Code 13

Code 13 =Limit or Flame Roll-Out Lockout

Diagnostic Light Sequence: 1-Short Flash, 3-Long Flashes (- , — — — )

► A Code 13 is generated when the limit circuit has been open for more than 3 minutes.  

► Auto-Resets after 3 Hours

CHECKOUT:

1. Check Blower Operation

• During a CODE 13 Lockout, the blower motor should be operating.
  • Blower Motor Operating → Step 2. Check Limit Circuit
  • Blower Motor Not Operating ⇒
    • Check for 120V between the Neutral "L2" bar of the control board and "HEAT".
      • Power + No Blower Operation = Bad Blower Motor or Capacitor ⇒ Check Capacitor
      • No Power = Bad Control Board ⇒ Try moving wire from "HEAT" to "EAC-1" for temporary operation.

2. Check Limit Circuit

• Check for 24VAC between Terminal 1  Red  on the 9-Pin plug of the control board and "24V COM".
• Check for 24VAC between Terminal 7  Red  on the 9-Pin plug of the control board and "24V COM".
  • Power on One Terminal Only = Open Limit Circuit → Step 3. Check Limits
  • Power on Both Terminals = Limit Circuit Closed ⇒ Reset the control board by cycling power and check operation.

3. Check Limits

• Main Limit
• Check for 24VAC between each side of the Main Limit and "24V COM".
  • Power on Both Sides = Limit Closed ⇒ Check Roll-Out Limits
  • Power on One Side Only = Open Limit
    • Open Limit + Cool Heat Chamber = Bad Limit Switch
    • Open Limit + Hot Chamber ⇒ Allow time to cool, then reset furnace.
• Roll-Out Limits
• Check for 24VAC between each side of the each Roll-Out Limit and "24V COM".
  • ​​​​​​​Power On Both Sides = Limit Closed
  • Power on One Side Only = Open Limit ⇒ Reset limit by pressing the limit reset button, reset the furnace and check for a bad heat exchanger.