When your furnace is not staying on, it’s not only a safety hazard but it’s also incredibly frustrating and uncomfortable. We heard you, dear callers. First and foremost, when your home is not adequately getting heated properly, there are some things you can do to troubleshoot your furnace. Let’s explore some steps you could take before calling your local plumbing company for help.
Initial Steps Before Troubleshooting
Firstly, it’s important to ask yourself: Are you comfortable and confident to troubleshoot your heating system yourself? If you answered ‘YES’ then let’s explore what the potential cause of your furnace not staying on may be. One or several variables may be contributing to your problem.

Remember that troubleshooting the problem is all that you are doing, not trying to FIX the problem. You may cause further damage to your furnace and in addition, it can be dangerous.
Secondly, grab your owner’s manual for your furnace. Often, you’ll find troubleshooting support or a FAQ section in your manual.
Additionally, take a photo of your furnace label which you can find on the front or side of the system. Since each heating system is made differently, you may find some useful advice online for your specific system.
Troubleshoot: When Your Furnace Not Staying On
To determine what could be causing your furnace to not stay on, you’ll want to investigate your current systems. Here are some common problems that often cause furnaces to turn on and off:
- Malfunctioning Thermostat: When is the last time you replaced your batteries? This will be the first thing to investigate before moving on to the following suggestions. If you’ve replaced your batteries and your heat doesn’t work, you may want to call a professional or replace it entirely.
- Dirty Air Filter: When your filter is full, your airflow is blocked and your heating system may stop working to protect you from a potential house fire. If it’s dirty, replace it.
- Check Your Pilot Light: Do you have a gas furnace? If so, you’ll want to investigate whether your pilot light has gone out. Grab your handy manual to explore what steps to take next. If you don’t feel comfortable relighting your pilot light, you may want to contact your go-to plumbing company for assistance.
- Flame Sensor: Now that you know the pilot light is ON and your furnace is still not heating your home, the next step is checking your flame sensor. It may be dirty or malfunctioning. Look for how to identify the sensor, how to clean it, or replace it.
- Limit Switch: When your furnace gets overheated, a safety feature called a limit switch may shut off your system entirely to protect you. Sometimes it may prematurely act up if your limit switch is malfunctioning.
- Check Your Circuit Breaker: Is it possible that your fuse is blown or your circuit tripped? Try resetting your circuit breaker to see if that turns your furnace back on.

In Summary
To wrap it up, when your furnace won’t stay on, it can be a simple fix or potentially numerous problems all at once. This is why preventative maintenance for your furnace is very important to minimize costly repairs. By getting to know your furnace, you’re not only empowered and knowledgeable but you’ll begin to understand how to take better care of your heating system. We hope this article was able to lend you some insight into how to troubleshoot your furnace that won’t stay on.

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Were you able to troubleshoot and diagnose it successfully?
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