How do you fix code 13 on a furnace?

It means that the high limit or flame rollout switch is open. This can lead to error code 13, Limit Circuit Lockout. Error 13 means that the limit or flame rollout has been open for more than 3 minutes. To address this issue, we need to ensure the furnace has proper air flow, and increase it if necessary.

What is code 13 on a furnace?





13 is limit circuit lockout, in which case your furnace would try and restart after 3 hours. The limit circuit is there to protect the furnace from overheating if there is insufficient airflow through the heat exchanger taking the heat away from the furnace and pushing it into your ductwork.

What does code 33 mean on a carrier furnace?

Error Code 33. On a Carrier furnace, it means restricted air flow, and I’ll never forget it.

How do you fix code 13 on a Payne furnace?

CODE: 13. RESULT: LIMIT SWITCH LOCKOUT- Indicates the occurrence of 10 successive limit trips during high heat or three successive limit trips during low heat. Auto reset after three hours. Check for *Improper or misaligned limit and/or limit shield.

How do you fix code 13 on a Rheem furnace?

Press and release the raised red button at the center of the flame roll-out switch to reset the furnace. You can press the reset button up to three times before troubleshooting the furnace’s internal components or calling for repair service; allow 30 minutes between each reset.

How do you reset the ignition lockout on a furnace?





Most modern gas furnaces can be reset by turning off the power, waiting around 20 seconds, then switching the power back on. Other furnace models may exit lockout after 1-2 hours and attempt to power on again. If your furnace has a pilot light, you may need to relight it following the manufacturer’s instructions.

How do I reset my carrier furnace lockout?

Though lockout mode errors and resets do vary from manufacturer to manufacturer, most use a simple reset procedure that involves turning power off to the furnace for thirty seconds or longer and turning it back. The interrupted power supply clears the lockout and will allow the unit to attempt normal operation again.

Can I run my furnace without a filter?

NO. A furnace filter has a critical job to perform and a filter cannot be run without one. For a furnace to work properly, it should always be equipped with a clean, working filter. As we’ll see, a dirty filter can cause problems, and so can having no filter at all.

What causes a limit circuit fault?

[7] LIMIT CIRCUIT LOCKOUT — Lockout occurs if the limit or flame rollout switch is open longer than 3 minutes or 10 successive limit trips occured during high-heat. Control will auto-reset after 3 hours.

Where is the high limit switch on a furnace?



The high limit switch consists of a long temperature-sensing probe attached to a metal mounting plate. From the mounting plate, the switch is wired to the blower fan motor and to the gas valve. The switch is generally located just past the heat exchanger. This is so that it can detect the temperature of the supply air.

How do you know if a limit switch is bad?

The most common sign of a malfunctioning limit switch is the continuous operation of your furnace’s blower. Just as the limit switch won’t allow the fan to turn on until the warm air has reached the right temperature, the limit switch also shuts down when the air cools to a certain temperature.

What causes high limit switch on furnace?

A high limit switch will keep tripping due to a dirty flame sensor, short cycling, obstructed airflow, or a defective switch. These lead to overheating within the gas furnace that triggers tripping as a safety measure to prevent fires. Clean and replace dirty and worn-out parts to fix the problem.

What does a tripped limit switch look like?



The most common way to tell if a limit switch is tripped is to observe the behavior of your furnace: Your furnace’s heating cycles end right after they begin. If the furnace won’t ignite, but the blower fan stays running, then the high limit switch might be tripped.

Can you run a furnace without a limit switch?

Without a functioning furnace limit switch, a furnace would not be able to regulate the temperature in conjunction with a thermostat. Typically, a furnace limit switch consists of an exterior plate and a temperature probe that lives inside the furnace housing.

What conditions can cause the limit switch to open during furnace operation?

If the supply air is too hot, the interior of the furnace overheats, which can cause damage to components. The limit switch trips when temperatures are too hot, effectively shutting down the system and locking furnace operation until the unit cools.

How do you test a limit switch on a gas furnace?

Youtube quote:To test the component. You can disconnect the wires. And check the resistance value across the contacts to see if it's open right now this switch is closed.