Clean Furnace Flame Sensor

Clean Furnace Flame Sensor. It’s hard not to notice that the weather is cooling down, which means it’s time to make sure your furnace is in good working condition before making sure you’re warm and cozy at home.

Other than changing the air filter, you should turn on the furnace and make sure everything is working properly if the furnace starts but then stops after a while.

If you can’t seem to get enough heat coming through your venting, there might be a problem with a dirty or defective flame sensor. This part isn’t available here at Peak Appliance Parts; check it out elsewhere first.

Clean Furnace Flame Sensorclean furnace flame sensor

We usually advise that you schedule furnace maintenance every 1-2 years for optimum indoor air quality and a smooth-running system. That’s the minimum, but you can also opt to have your ducts cleaned at that time too. Or have them done separately.

Shut Down The Power

If you are working around a furnace, you definitely don’t want it to cycle on, because no one should ever work near it without being sure that everything is turned off.

So, in order for you to be sure about the power being cut off, head over to the circuit breaker box and turn it all off.

Once you’re positive that everything has been turned off, press your ear against the furnace and listen out for any whirring sounds. If nothing turns on after a few moments of listening closely, then you’re safe to proceed with checking the gas valve itself.

Eliminate The Flame Sensor

At one end of the burner housing, there’s a combustion sensor that is hooked up to the gas valve. The loner in which the connector is attached will determine how you go about removing it.

The first thing that you’ll need to do is locate and remove the screws holding it in place. Once you’ve removed them, find out if there is any other way of accessing it, like through a panel or similar method. Be sure not to lose any of those screws so you can reattach the new sensor after taking it off.

Get Rid of Carbon Buildup

Using 400-grit sandpaper or fine steel wool, sand the metallic surface of the flame sensor. Avoid exerting too much pressure, otherwise, you might weaken the structure of the sensor or break it completely.

You want to keep your flame sensors working perfectly throughout their lifestyle by avoiding situations that may cause even more damage and force you to throw them out.

If you feel like there is a chance your carbon deposits may have already burnt through the metal, then it’s best if you go ahead and replace that piece of equipment so there won’t be any doubts in your mind in the future.

Clean The Rod With A Solvent

Using either acetone or lacquer thinner, wipe the metallic rod with a paper towel or fine steel wool. Keep rubbing until no more black residue comes off on a cloth or towel.

When you’re done, the rod should be shiny. Wear a respirator while using any solvents so they don’t make you sick when breathed in and keep them away from open flames such as lighters.

Replacing The Sensor

Position the sensor on the flame, ensuring that you are holding it as far into it as you were when you removed it. Then, tighten the sensor by hand so that it’s secure.

The vibrations from the blower could cause this to back out if there is not enough pressure holding it in place. Reinstall the electrical connector onto the base of the rod. We recommend tightening these screws with a screwdriver, so there is sufficient pressure to endure their use over time without falling out.

Furnace Restart

Turn the switch back on if you have to, open the valve for the gas, and set the thermostat to a high temperature in order to get the furnace to kick on.

If the blower comes on and warm air starts blowing, then it’s safe to say that everything is in working order. Then you should seal up your unit once again.

Importance of Cleaning

A dirty air filter can’t do its job very well. Over time, dust and debris may accumulate on the sensor, which could potentially lead to an issue where the furnace keeps calling for heat when it shouldn’t be something you want the winter season. But cleaning off the flame sensor may be all it takes to get the system working properly again.

Clean Furnace Flame Sensor

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