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Why does my furnace shut off after a few minutes?

If your furnace turns off after a few minutes, there is a good chance it is caused by a faulty or dirty flame sensor. This vital component is designed to keep an eye on the gas burner. When it cannot sense that burner, the furnace runs then shuts off and starts again.

What does it mean when a furnace is short cycling?

Short cycling means that the furnace turns on and off very frequently with little time between on and off. In some cases, it may not make any heat at all before shutting down.

What would cause a furnace to keep shutting off?

If your furnace keeps shutting off, it could be due to low airflow. There are several indirect issues that cause low airflow. Dirty Air Filters. If you don’t change your air filters often enough, the filters will become dirty and clogged, which means the heat exchanger retains heat and eventually causes it to overheat.

What causes a gas furnace to short cycle?

The most likely cause of short cycling is the fan limiter, which prevents fires and furnace damage by shutting the system down if the heat exchanger becomes too hot. A dirty flame sensor or damaged thermocouple will shut off the gas valve and the furnace. This prevents natural gas accumulations that could cause a fire.

Can a bad thermostat cause a furnace to short cycle?

A broken or poorly placed thermostat can cause short cycling. A thermostat positioned near a heat source or in direct sunlight can warm too quickly, signaling your furnace to shut off before the entire home is adequately warmed. This sometimes causes short cycling, depending on your temperature setting.

Is a short cycling furnace dangerous?

Short cycling doesn’t necessarily pose a threat to your health, but it can absolutely destroy the furnace if it isn’t properly addressed in time.

Will a furnace shut off with a dirty filter?

The Filter is Dirty and Clogged A dirty and clogged furnace air filter will not only prevent proper air filtration, but it will actually obstruct airflow to the heat exchanger. If the heat exchanger gets too hot from lack of airflow, a safety mechanism will shut the furnace off to protect it.

Why does my furnace filter get so dirty so fast?

One-inch pleated filters quickly get dirty because they’re designed to catch more airborne contaminants. Think of 1-inch pleated air filters as a fine fish net with a very small gaps: it catches everything from big to small fish, but that also means the net fills up with fish faster (say that 3 times fast).

Can a dirty furnace filter make you sick?

If your furnace filter becomes dirty then it can no longer remove these 10 airborne pollutants. Unfortunately, this can cause problems like mold to spread through your duct work. So yes, having a dirty furnace filter can make you sick.

What problems can a dirty furnace filter cause?

A clogged furnace air filter will negatively affect the airflow throughout your house and HVAC system. The lack of fresh air in your furnace will cause the heat exchanger to become too warm and deactivate. Dirty filters indirectly cause short cycling issues and will make it hard to keep your home warm.

How dirty should my furnace filter be?

A good rule of thumb is to change 1-2 inch filters every three months, 4 inch filters every six months and 5 inch filters every 12 months. Signs your air filter needs changed: The filter is visibly dirty. Certainly if you can’t see the material of the filter itself, it should be replaced.