Payne PG8MAA Error Code 13: Limit Circuit Lockout

What Does Code 13 Mean?

Status code 13 on the Payne PG8MAA means the Integrated Furnace Control (IFC) locked the furnace out because a limit or flame-rollout switch remained open for more than 3 minutes. These switches open when the furnace overheats, so the lockout protects the heat exchanger from excessive temperature.

Code 13 is the escalation of status code 33 (limit circuit fault). When a limit switch first opens, the board flashes 33 and runs the blower to cool things down; if the switch stays open past 3 minutes, the condition escalates to the 13 lockout. The control auto-resets after about three hours, but it will lock out again if the underlying restriction remains.

On this single-stage, multipoise furnace the overwhelmingly common trigger is restricted airflow — most often a clogged filter, but also closed or blocked supply and return registers. Less common causes (a defective blower motor or capacitor, or a flame-rollout switch tripped by inadequate combustion air) are not homeowner repairs. Note that a tripped flame-rollout switch must be manually reset by a technician and points to a combustion problem, not just airflow.

What You'll Notice

• The furnace runs, heats briefly, then shuts down and will not restart for up to three hours.
• Air from the registers feels very hot right before the shutdown.
• The filter is visibly gray, clogged, or long overdue for replacement.
• Some supply or return registers are closed, blocked by furniture, or covered.

Common Causes

How to Fix It: Restore airflow by replacing the filter and opening registers

What You'll Need

• Replacement furnace filter (correct size) 🛒 Find at FiltersFast · 🛒 Find at Amazon
• Flashlight

Steps

1. Turn off electrical power at the breaker and shut off the gas supply valve before servicing Switch the furnace breaker or power switch to OFF and turn the manual gas shutoff valve to OFF (perpendicular to the pipe). If you smell gas, leave immediately and call your gas company.
2. Inspect and replace the air filter Locate the filter in the return duct or blower compartment. Hold it up to a light — if you cannot see through it, replace it with a new filter of the same size, oriented so the airflow arrow points toward the furnace.
3. Open and clear all registers and returns Walk the house and make sure supply and return grilles are fully open and not blocked by rugs, furniture, or closed doors. Choking off return air is a common overheating cause.
4. Restore power and gas, then run a heat cycle Turn the gas valve and power back on. Because the board may still be in its up-to-three-hour lockout, you can cycle the furnace power off for about 30 seconds to clear the lockout, then set the thermostat to call for heat.

When to Call a Professional

Contact a licensed HVAC technician if:

• Code 13 returns even after the filter is replaced and all registers are open
• You see or smell evidence of flame rolling out at the burners, or the flame-rollout switch has tripped
• The blower does not run, runs very slowly, or is noisy, suggesting a motor or capacitor fault
• The lockout repeats and going further would require testing the blower, limit switch, or rollout switch

✓ Verified against manufacturer service manual — March 2026