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How do I know if my furnace flame sensor is bad?
Signs of a bad flame sensor Furnace burners turn on but go out after a few seconds. Soot and other debris is covering the end of the sensor (cleaning the flame sensor may fix this issue rather than a flame sensor replacement) Tip of flame sensor is black. Porcelain/sensor casing is cracked.
What can you clean a flame sensor with?
Next, get a very light grain sandpaper, a wire brush, or steel wool. Use this to rub the metal rod gently, and only the metal rod, to clean the dirty flame sensor. You’re not sanding down a rusty car, here; you’re just trying to get rid of grit and buildup on the sensor.
Can you clean a dirty flame sensor?
What happens if furnace flame sensor is dirty?
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 do you trick a flame sensor?
Luckily, making such a check is very easy: Take a multimeter with microamps (µA) measuring system. Keep the furnace system turned on. Connect it to the wire that is leading to the gas valve. Connect the other side of the multimeter to the sensor terminal. Take the lead away from the flame sensor.
Can you use sandpaper to clean flame sensor?
To clean the sensor, simply rub the metal rod gently with light grit sandpaper, steel wool, or emery cloth to eliminate the carbon buildup. Note: Never use sandpaper as it will damage your flame sensor’s rod. After that, use a clean and dry paper towel to get the excess particles and dust from the metal rod.
How much does it cost to clean a flame sensor?
If they are part of a routine maintenance service, they will cost about $200. Similarly, flame sensors often become too dirty and malfunction, but these sensors can be fixed with a thorough cleaning. However, if it’s too far gone and you must replace the flame sensor, it will cost you anywhere from $80 – $250.
How often should you clean your flame sensor on your furnace?
A good rule-of-thumb is to change your filters every two to three months and to have the furnace fully cleaned once a year. The best time to clean your gas furnace is during the warmer months where you do not need to heat your home.
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.
What does dirty flame sensor look like?
The flame sensor can become corroded due to carbon buildup from the flame. If the burner light goes out within seconds of switching on the unit, this is a telltale sign of a dirty sensor. If you see soot clearly covering the sensor, then it’s time for a cleaning.
How much is a flame sensor for a furnace?
Flame Sensor 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.
Can a furnace run without a flame sensor?
The flame sensor is an important safety feature inside a furnace. Without the flame sensor, if the pilot light goes out but the gas valve remains open, the gas will not burn and will seep out of the furnace. This is a dangerous situation that can result in gas poisoning or even an explosion.
What does a broken flame sensor look like?
Signs of a bad furnace flame sensor are: 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.
Can hear your furnace click on but it does not fire up?
The Pilot Light (Faulty Ignition Sensor) The pilot light or ignition sensor is usually the most common issue when your furnace will not ignite. This is typically the problem if you can hear your furnace click on but it does not fire up. If the sensor or ignitor is dirty, it will need to be cleaned.
How does a furnace flame sensor work?
A furnace flame sensor works by detecting the presence of a flame within the furnace. As the gas valve opens to begin the combustion process, the current is sent out from the sensor in order to detect the presence of heat from a flame.
What does it mean when a furnace is short cycling?
Furnace short cycling refers to the switching on and off of your furnace system without reaching the set temperature on the thermostat. And for those experiencing short cycling, you may notice suddenly that your home isn’t as warm as it should, leaving you and your loved ones cold and uncomfortable.
