When temperatures fall below zero and snow is on the ground, a furnace problem can become urgent. On one such day in Edmond, with the temperature around −3°F, ARP Heat And Air handled an emergency furnace repair involving a bad limit switch.
Our technician identified the faulty limit switch and replaced it. After the repair, the furnace was heating normally again. This Edmond call is a reminder that a heating problem is not always a reason to replace the entire system: finding the affected component helps determine the appropriate service.
Why a furnace limit switch matters
A furnace high-limit switch is a safety control designed to interrupt heating if the furnace becomes too hot. If a furnace repeatedly shuts down, the cause might be an airflow restriction, a blower issue, a faulty control or another problem. The equipment needs to be checked to determine what is actually happening.
A limit switch should never simply be bypassed. The technician needs to address the underlying cause of the problem and ensure the appropriate safety control is in place. The right repair depends on the system and the findings.
What to do when your furnace needs help in extreme cold
Check that the thermostat is set to heat and above the room temperature. If the filter is easy to access, look for a visibly dirty filter and replace it with the correct size and type if needed. Note any thermostat message or unusual sound so you can describe it when you call.
Do not open furnace panels, bypass safety controls or repeatedly reset a tripped breaker. If your home is becoming unsafe in the cold, move people and pets to a warm, safe place while arranging help. Never use an oven, outdoor heater or grill to heat your home.
If you smell gas, leave immediately without operating switches or using a phone inside. From a safe place, call 911 and your gas utility. If a carbon monoxide alarm sounds, go outside to fresh air, call 911 and do not reenter until emergency responders say it is safe.