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Why does my furnace flame keeps going out?

Jim Brown

Why does my furnace flame keeps going out?

Possible causes: Overheating. Your furnace has a limit switch that keeps it from running if the heat exchanger is too hot. Dirty filters, closed or blocked vents and other blockages in airflow are common causes of an overheated furnace.

What does it mean when the pilot light won’t stay lit?

thermocouple
If your pilot light won’t stay alight, it might be the thermocouple. Sometimes dust buildup collects on the thermocouple and blocks the sensor. Try cleaning the thermocouple and then relighting the pilot light. If it continues to go out, the thermocouple might need to be replaced.

How often should you clean your furnace flame sensor?

Generally speaking, the flame sensor should be replaced every two to three years as preventative maintenance. Some technicians also recommend changing it any time that there is a flame current issue.

Why does my gas furnace light keep going out?

If there isn’t the right amount of gas for your pilot light, it won’t be able to keep the thermocouple happy. Your gas valve may need to be adjusted or replaced. If you are trying to light a standing pilot light on an old furnace but it keeps going out, make sure you are holding the pilot button long enough.

What should I do if my furnace won’t ignite?

If your problem is not with your gas line, see if your pilot light is lit, since your pilot light or ignition sensor is the most common culprit behind a furnace that won’t ignite. If this is your first time turning on your furnace this season, keep in mind that it may take a little extra time for the pilot light to turn on.

What should I do if my furnace pilot light is off?

Check the Thermocouple. Your furnace’s thermocouple, if it works normally, checks to see whether the pilot light is on or off. Thermocouples detect pilot lights by sensing the heat they produce. If it determines that the pilot light is off, it shuts down the flow of gas.

How does a faulty thermocouple shut down a furnace?

Thermocouples detect pilot lights by sensing the heat they produce. If it determines that the pilot light is off, it shuts down the flow of gas. While this is an excellent safety feature, a faulty thermocouple may decide arbitrarily that your pilot light is off when you want it on, shutting down your pilot light and your furnace.

Why does my furnace flame keeps going out?

Jim Brown

Why does my furnace flame keeps going out?

Possible causes: Overheating. Your furnace has a limit switch that keeps it from running if the heat exchanger is too hot. Dirty filters, closed or blocked vents and other blockages in airflow are common causes of an overheated furnace.

What causes a furnace to not stay lit?

Bad Thermocouple However, a malfunctioning thermocouple may lose the ability to sense heat from the pilot light, causing it to close the gas valve at random. If your furnace doesn’t stay on, check the pilot light. If the pilot light won’t stay lit, a bad thermocouple could be to blame.

Why does the pilot light on my furnace not stay on?

However, a malfunctioning thermocouple may lose the ability to sense heat from the pilot light, causing it to close the gas valve at random. If your furnace doesn’t stay on, check the pilot light. If the pilot light won’t stay lit, a bad thermocouple could be to blame.

What to do if your furnace won’t stay on?

If your furnace doesn’t stay on, check the pilot light. If the pilot light won’t stay lit, a bad thermocouple could be to blame. You may need a professional to take a look and replace the malfunctioning part. 3. Full Condensate Pan Newer condensing furnaces generate condensate, which drips into a pan and drains away.

Why does my Furnace Fan keep running even when the light goes out?

The fan continues to run even though the flames and pilot light go out. Possible causes: Overheating. Your furnace has a limit switch that keeps it from running if the heat exchanger is too hot. Dirty filters, closed or blocked vents and other blockages in airflow are common causes of an overheated furnace. A bad limit switch.

Why does my Lennox Furnace not stay on?

This feature is not available right now. Please try again later. My Lennox gas furnace wouldnt stay on for more than 15 sec. It goes into shut down mode after 4 failed attempts staying on. This issue could be caused by a dirty heat temperature sensor. The sensor detects if the gas ignites and flames are present.

Why does my furnace flame keeps going out?

Jim Brown

Why does my furnace flame keeps going out?

Possible causes: Overheating. Your furnace has a limit switch that keeps it from running if the heat exchanger is too hot. Dirty filters, closed or blocked vents and other blockages in airflow are common causes of an overheated furnace.

Why does my furnace only run for a few seconds?

If your furnace only runs for a few minutes then flips off automatically, the flame sensor might be faulty. The flame sensor is responsible for monitoring the gas burner. The problem can be solved by merely cleaning the flame sensor, but if the issue persists, you may have to get the flame sensor replaced.

What does it mean when your furnace won’t stay lit?

If your furnace’s pilot light won’t stay on, the furnace won’t work. Some common causes include issues with the thermocouple and pilot tube. A faulty thermocouple may arbitrarily determine that the light is off when you want it on and vice versa. It could simply be that the thermocouple is bent.

Why does my furnace keep starting and stopping?

When a furnace keeps turning on and off, it is usually due to short cycling. This is the term used to describe problems originating from within the heating system. If short cycling is not promptly diagnosed and corrected, it could cause permanent damage to your heating unit and higher utility bills.

How do I know if my thermocouple is bad on my furnace?

If you can’t get the flame to light at all, and you’re sure the gas is on, there’s probably an obstruction in the pilot tube. If the flame lights and goes out when you release the gas control knob after holding it in for the recommended 20 to 30 seconds, that’s the sign of a thermocouple malfunction.

Why does the pilot light on my furnace not stay on?

However, a malfunctioning thermocouple may lose the ability to sense heat from the pilot light, causing it to close the gas valve at random. If your furnace doesn’t stay on, check the pilot light. If the pilot light won’t stay lit, a bad thermocouple could be to blame.

What does it mean when your furnace won’t stay on?

One of the most common furnace problems is when the burners won’t stay lit. This causes the furnace to fire up, heat for a few minutes, and turn back off before it has had time to reach the target temperature. Below are a few possibilities why your furnace doesn’t stay on and what to do about it.

What should I do if my gas furnace won’t light?

Once you light the pilot, you need to keep the button depressed for at least 30 seconds (sometimes up to 1 minute). This gives the flame enough time to heat the flame sensor (thermocouple) that tells your furnace it’s OK to light the burner. If it’s still not working, it may be one of the problems above.

What happens when you turn on a gas furnace?

Situation: You turn the thermostat up, the furnace ignites and the burner comes on. The furnace stays on for awhile (maybe 1 minute, maybe 10 minutes) and then goes out. The fan continues to run even though the flames and pilot light go out.