Why does my furnace ignitor keeps burning out

A furnace control board where the ignitor relay on the control board is stuck closed and keeps the ignitor burning all the time. … Debris from the heat exchanger or bugs/spiders can get on the ignitor while the furnace is not calling for heat and when there is a call for heat the debris/bug can short the ignitor out.

Why does my igniter keep going out in my furnace?

As mentioned above, sometimes the cause of a furnace ignitor failing to ignite is due to a safety issue, such as a clogged air filter, for instance. … So, if your furnace is failing to ignite, it’s a good idea to check the air filter. If it looks clogged up, then this is probably the source of the problem.

How often do furnace ignitors fail?

According to the Gas Furnace Guide, ignitors have an average lifespan of four to seven years. So, after about seven years, you may have to replace the ignitor; however, you probably won’t have to replace the entire furnace because other parts, such as the heat exchanger, can last more than 15 years.

How long should a furnace ignitor last?

Fortunately, you can replace the ignitor without replacing the full furnace. Most ignitors last about seven years. Keep reading to learn how you can tell if your furnace problem is a faulty ignitor.

How do you diagnose a bad furnace ignitor?

1. The Furnace Stops Running. When a furnace won’t run at all, check for a bad ignitor. …
2. Your Furnace Blows Chilly Air. Unless you’ve set your thermostat to COOL, your furnace should not blow cold air. …
3. Does Your Furnace Short Cycle? …
4. A No Glow Ignitor. …
5. We Can Replace Your Furnace Ignitor.

What does a hot surface igniter do?

Hot surface ignitor are the most commonly used electronic ignition system. It works like a light bulb filament, heating up when electricity is passed through it. Most are made from silicon nitride or silicon carbide ceramic. When the gas valve opens, the gas is ignited by the igniter.

How much does it cost to replace furnace ignitor?

Here’s the bottom line: Whether for a natural gas furnace, oil, or a propane furnace, replacing a furnace ignitor–including parts and labor–will cost you around $300 – $425 for a qualified contractor to install. Compare that to, say, a draft inducer motor, which will cost $400 – $1,500 to replace.

How long do flame sensors last?

Flame sensor lifespan If you’ve just replaced the sensor or had a new furnace installed, you can expect the flame sensor to last for about five years. The average lifespan of a furnace is 15 to 30 years, so you can anticipate a flame sensor replacement once or twice over the course of your homeownership.

How do I get my furnace to kick on?

1. Check your circuit breakers.
2. Check your thermostat settings.
3. Ensure your furnace filters are clean.
4. Check your pilot light.
5. Check your blower motor.
6. Check the furnace ignition switch.

What causes a dirty flame sensor?

It is a sensitive sensor so any type of dust or carbon buildup could cause it to malfunction. Most people have their furnaces in a basement or laundry area where there is excess dust in the air. This dust could stick to the sensor making it dirty and causing your furnace to shut down.

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Where is the flame sensor located?

A furnace flame sensor is a very basic part of your furnace. It’s located on the burner assembly and is just a thin metallic rod. It’s usually bent, and it sits just in front of the pilot flame inside the furnace.

Is it hard to replace furnace ignitor?

The igniter gets very hot then cools down repeatedly to heat the furnace to the temperature you desire. … Qualified Technician: Most homeowners will agree that furnace tune-up and replacing an igniter is relatively easy.

Is hot surface ignitor the same as flame sensor?

The hot surface igniter is strategically located for ignition purposes. The flame sensor senses the fire and continues allowing the gas valve to feed gas to the burners.

What is the difference between flame sensor and igniter?

The flame sensor is able to detect the heat caused by combustion. When it does, it sends the signal to stop powering the hot surface igniter. If, on the other hand, a certain period of time elapses in which the flame sensor cannot detect a flame, it will automatically shut off the gas valve.

What is a hot surface ignitor made of?

Hot surface igniters are a more recent development. These electrical apparatuses are constructed from a substance such as silicon carbide. When the furnace is turned on, electricity flows into the igniter, causing it to glow red hot.

Can thermostat cause furnace not work?

1. Thermostat Issue. One of the first things to consider when your furnace isn’t working is that your commands are simply not reaching the machine, meaning there could be a problem with the thermostat you use. The issue could be as simple as a lack of power, as some need batteries to operate.

How long should it take for a furnace to ignite?

A furnace should take around five minutes to start once you’ve turned on your thermostat. That said, you might end up waiting closer to ten minutes to see your furnace kick on if it’s older or has an issue with its pilot light. If this is the case, it may need to be checked out by a professional.

What is a furnace flame sensor made of?

A flame sensor is nothing more than a stainless steel rod partially encased in porcelain. By itself, it does nothing. There are no moving parts, no switches. When attached to a control module, the module sends out an A/C voltage to the sensor.

Can you bypass the flame sensor on a furnace?

Well, while disappointing to some readers, here is the answer: No, bypassing the flame sensor isn’t a solution. You won’t find steps to bypass the flame sensor anywhere. … Attempting to bypass the flame sensor is not a good idea, even if it were possible. The flame sensor is an important safety feature on your furnace.

When should I replace my flame sensor?

Unless the flame sensor is physically damaged or broken, you typically won’t have to replace it. They last a fairly long time, so most issues involved in the part not working right usually boil down to a fixable error.

What symptoms would a furnace with a dirty flame sensor exhibit?

• The furnace lights but then shuts down after a few seconds (short cycles)
• The porcelain on the flame sensor is cracked.
• The flame sensor is sooty or corroded.

Do all gas furnaces have a flame sensor?

Not all furnaces have a flame sensor, but if your furnace has one, it will be mounted close to the burner with the metal rod positioned in the flame. Flame sensors vary in size (2 to 4 inches) and shape (see examples below).

What does the furnace board do on most modern furnaces?

What does the furnace board do on most modern furnaces? Controls the ignition, safety, and blower operation. If pulsed DC current is not present in the flame rod, what is the effect on the gas valve in a direct spark-ignition system? The valve will remain closed.

What voltage is a furnace ignitor?

Most are made from silicon nitride or silicon carbide. The igniter is positioned in the flow of gas entering the burners. When the thermostat calls for heat, 24 volts are sent to the electronic ignition control module, which energizes the furnace blower and other systems and sends 120 volts to the HSI.