Why is my gas furnace not staying lit?
Probably the most common issue when dealing with a furnace that will not stay lit or ignite consistently is a dirty flame sensor. The flame sensor acts as a communication vehicle with the circuit board and tells it when a flame is lit inside the furnace.
What do you do when 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.
What causes a furnace to light then go out?
Another reason why a furnace ignites then turns off could be related to the flame sensor. This key component senses when the flame is on. It then alerts the control board to begin blowing warm air. Often, dust or dirt covers the sensor.
Why does my furnace turn off after a few seconds?
A common reason a furnace short cycles is because the heat exchanger, the part that heats your air, is getting too hot due to a lack of airflow. Once the heat exchanger overheats, it trips the high limit switch, which shuts the furnace down to protect it.
Why does my furnace only runs for 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.
How do I stop my furnace from short cycling?
Quote from Youtube video: And the cycle will continue again and again so you can easily prevent this type of short cycling by simply changing the air filter on the furnace.
Can a bad thermostat cause a furnace to short cycle?
A faulty thermostat can be a possible culprit for short cycling. If you’re experiencing a furnace short cycling, the first and easy thing you can do is check your thermostat to see if it’s performing correctly. Many times, a homeowner may forget to switch their thermostat over to the heating mode.
How do you fix short cycling?
How To Stop and Prevent Short-Cycling
- Check your air filter. Believe it or not, a clogged air filter can cause a wide variety of air conditioning issues. …
- Check your thermostat placement. …
- Check your air conditioner’s refrigerant levels. …
- Replace the low-pressure control switch. …
- Check the compressor.
What are the symptoms of a bad furnace thermostat?
7 Signs You Need to Replace Your Thermostat
- Your HVAC Keeps Turning On or Off. …
- Faulty Thermostat Readings. …
- Suspiciously High Energy Bills. …
- Constant Temperature Shifts. …
- Thermostat Is Too Old. …
- Thermostat Fails to Respond to Changed Settings. …
- Your HVAC System Short Cycles.
How do I know if my furnace flame sensor is bad?
6 Signs of a Malfunctioning Gas Furnace Flame Sensor
- Yellow Burner Flames. Open up or glance through the peephole of your gas furnace to see the color of the flames firing up in the burner. …
- Rusted Flue Lines. …
- High Utility Bills. …
- Water Leaks. …
- Old Age. …
- Constant Thermostat Adjustments.
How much does it cost to replace a furnace flame sensor?
It stops your furnace from letting off large amounts of natural gas if it’s not working properly. If the sensor is bad, it won’t be able to sense heat and will turn the furnace off. The average cost to repair or replace a flame sensor is between $75–$200.
How do I know if I need a new flame sensor?
First, check for your gas burners to light up and then go out after a few seconds. This is the most common sign of a sensor issue. Second, if you can actual see soot covering the tip of the sensor, it’s time for a cleaning. If you look at the tip and it’s black, it’s time for service.
What happens when flame sensor goes bad?
If your flame sensor is dirty or faulty, it will automatically shut down the heating unit if it doesn’t detect a flame. Most furnaces will go into a safety ignition lockout when a shutdown happens three times.
How often should a flame sensor be replaced?
Even if the flame sensor is in proper working order, it is advised that you replace it every two or three years as a preventative measure.
How do you reset the flame sensor on a furnace?
Quote from the video:
Quote from Youtube video: That's holding a little bracket on the top. And we're going to remove the thermocouple and we're just going to take a little sandpaper. Actually the best is an Emery cloth.
