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Why Does My Furnace Keep Turning Off

When your furnace repeatedly shuts off and on, your unit won’t be able to adequately heat your home. This can be extremely uncomfortable, especially during the winter months.

There are a number of reasons why your furnace keeps turning off. So let us look at some of the most common culprits.

Faulty Thermostat

Faulty Thermostat

If your furnace keeps turning off, the first thing you should check is your thermostat. Most furnaces have a built-in thermostat that controls when the unit turns off. If you’re experiencing problems with your furnace turning off, check to see if your thermostat is set at an incorrect temperature. If so, reset it to the correct temperature.

Another reason your thermostat may be to blame is if it’s not wired correctly. If you’ve recently moved your thermostat or installed a new one, make sure that the wires are connected properly and that they’re not crossed.

The other reason your thermostat might not be working correctly is if it’s placed near a source of heat. If there’s a space heater or other heat source near your thermostat, this can cause the temperature reading to be inaccurate. The best way to fix this problem is by moving the thermostat away from the heat source.

Dirty Air Filter

The air filter is a crucial component of your heating system. It filters out dust, debris, and other pollutants that can accumulate in your ductwork and cause problems with airflow.

Over time, the filter can become clogged and no longer able to adequately filter the air before it enters your home. This can cause your furnace to cycle on and off as it struggles to maintain a consistent temperature.

In order to fix this problem, you’ll need to replace the filter with a new one. You may also want to consider cleaning the existing one with soap and water.

A good rule of thumb is to change your air filter once every month. This should help prevent the problems that can arise from having a dirty filter.

Faulty Ignition System

If your furnace keeps turning off, it’s probably because the ignition system is faulty. The ignition system is responsible for turning on and off the gas supply. If there are any issues with this system, it can cause your furnace to turn off several times during a single heating cycle.

There are a number of reasons the ignition system can be faulty. It could be a loose wire, shorted or blown fuse, or it could be a bad ignition switch.

To diagnose the cause of your problem, check the power supply to see if it’s still connected. If the wiring is secure, then check the fuse and replace it if necessary. If your furnace turns off again, then you might have a bad ignition switch or another component of the ignition system that needs to be replaced.

Broken Flame Sensor

The flame sensor is responsible for monitoring the flame inside your furnace and turning it on or off when needed. If there are any issues with this system, it can cause your furnace to turn off.

If you suspect that this is the problem, check your manual and see if you can find instructions for replacing this part yourself or if you need to call for an expert’s help.

Damaged Blower Motor

The blower motor is what helps distribute the heat through your home. It’s usually mounted on top of the furnace or inside it. If it stops working, it can cause your furnace to overheat, which will make it shut down to protect itself from damage.

If you suspect that your blower motor is damaged, look for signs that it might be broken, such as a loud noise coming from the unit or a burning smell. If so, call an expert to have it replaced.

Damaged Heat Exchanger

A heat exchanger is the component of your furnace that helps circulate hot air throughout your home. If it’s damaged, it can’t do its job efficiently and will cause your furnace to use more energy than necessary, which can lead to higher utility bills over time.

Apart from that, it can also cause your furnace to overheat, which will make it shut down to protect itself from damage.

If you’re having trouble with your heat exchanger, you’ll notice that your home is cooler than it should be or that it doesn’t seem to be getting warm at all. If this is the case, call an expert immediately.

They can inspect the unit and make any necessary repairs so that you can get back to enjoying a warm house without worrying about high utility bills.

An Oversized Furnace

If you’ve had a new furnace installed in your home, but it keeps turning off, it’s possible that the furnace is too large for the house.

If the furnace is too large, it will heat your home too quickly, and then the thermostat will turn off the unit. This can be a problem if you’re trying to stay warm and, therefore, need the furnace to run consistently.

Unfortunately, the only solution is to install a smaller furnace. If you’re not sure whether your furnace is too big, call an HVAC professional who can come out and inspect the unit. They’ll be able to tell you whether your furnace is too big for your home.

Blocked Vents

If your vents are blocked, the furnace won’t be able to pull enough air into the house. This can cause a variety of problems, including overheating and poor indoor air quality. If you notice that your home is feeling stuffy or there is an unpleasant smell in your house, it’s time to check for blocked vents.

Check the vents in each room and make sure there are no objects blocking the airflow. If you find a blockage, remove it immediately. If you can’t remove the blockage yourself, call an HVAC professional who can come out and take care of it for you.

What Is a Furnace Cycle?

A furnace cycle is the process your heating system goes through to heat your home. It begins with air being pulled into the furnace from outside your home, which is then heated in the unit’s burners. Once it has been heated, it is distributed throughout the house via ductwork. The cycle repeats as long as you need heat.

How Long Should the Typical Furnace Cycle Last?

The length of time it takes for your furnace to complete a cycle will vary depending on the size of your home. For example, if you live in an older home with smaller ductwork, then it may take longer for the heat to reach every room than if you had newer HVAC equipment installed.

You should also consider how cold it is outside when determining how long your furnace will take to complete a cycle. The colder it is outside, the longer you need to let your furnace run before it has warmed up all the rooms in your home. If you have an older thermostat that doesn’t measure temperature accurately and can’t adjust for weather conditions automatically, then this could be a problem.

How Can I Tell When My Furnace Needs Repairs?

If you’re having problems with your furnace, it can be difficult to know whether the issue is a simple fix or something that needs to be repaired by a professional. There are some telltale signs of a problem that you can look for, such as:

  • Your furnace is making unusual noises or rattling;
  • Your thermostat is not working properly;
  • Your furnace isn’t heating your home properly, even though you’ve adjusted the thermostat settings;
  • The pilot light keeps going out;
  • The furnace is not running at all;
  • You notice a burning smell or strange odors;
  • You notice that your furnace is leaking water onto the floor or dripping water into a pan.

If you’ve noticed any of these signs, it’s time to call a professional. They can help diagnose what is wrong with your furnace and fix it so that your home is comfortable again.

Final Remarks

If you find that your furnace is shutting off unexpectedly, it’s a sign that something is wrong with it. It could be a minor issue, but it could also be a sign of a larger problem. It’s best to call an HVAC technician if you notice this happening. If your home is cold and your furnace isn’t running, then it might be time for repairs or maintenance.

Generally, the best way to avoid furnace problems is to schedule regular maintenance with a professional HVAC technician. They can inspect your unit, check its parts for wear, and clean out any debris that may be clogging the system.

If you wait until something breaks down before getting an inspection and repair, it could cost more money in the long run, not to mention put your family at risk of being without heat during cold weather months.