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McDonald Home Services Blog

This is Why Your Furnace Stopped Working

There’s one little component in your furnace that’s vital to its operation, and vital to your health. We all know that there are some dangers associated with furnaces, which is why they have safety features built in–a flame sensor is one of those features.

We’ll explain what a flame sensor is, what it does, and what it means for your upcoming furnace repair in Sarasota. Spoiler alert: it’s not a DIY-friendly job, and needs to be handled by a technician. Now let’s explain why.

Your Flame Sensor Does What it Sounds Like it Does

It’s there to detect a flame. Your furnace uses gas, which means there’s a gas pipe going from your supply towards your furnace. As the gas comes out, it’s burned, and the flame sensor is able to detect the flame. It allows the flame to burn and continue operation while idly monitoring it.

When the flame goes out, the sensor stops the flow of gas through the pipe. It stops in its tracks so that gas doesn’t just keep pumping into your air supply in your home, risking the safety of your family.

When your furnace is given the signal to turn on and heat your home, but the flame sensor can’t tell if there’s a flame or not, it just looks like your furnace is busted from your point of view. If this is what’s happening to your furnace, it’s a safety feature that’s doing its job–but let’s explain how it gets mucked up in the first place.

It’s Dirty

That’s about the size of it: the flame sensor is dirty. Continuous use has coated it in soot and likely created small flakes or bits of debris that’s clogging it up. Because that’s all in the way, it can’t tell if there’s a flame even if one is burning brightly and causing your furnace to operate normally. When it can’t detect it, the safety protocol kicks in and kills the flow of gas.

Now it Needs a Detailed Cleaning

Flame sensors are designed to work through soot and buildup over time, which is how you know the situation must be pretty bad if it can’t even work under these conditions. An HVAC technician needs to stop the gas line, power down your furnace, disassemble the flame sensor, clean it, and put it back in its place.

Here’s Why You Can’t be the One to Clean it

First of all, it will void your warranty. Nearly all HVAC equipment from furnaces to air conditioners include information in the warranty section that dictates a trained and/or certified HVAC technician must be the one to perform maintenance and repairs. And this falls directly under that category. If you don’t listen, it can void your warranty.

Beyond that, technicians are trained to handle repair requests like these. They know these components inside and out, and how to know if they’re put back into place properly. They also inspect the operation afterwards to make sure everything is exactly where it should be. When it comes to safety features, DIY isn’t a good choice.

Let’s Fix That Flame Sensor

If that flame sensor is what’s causing you strife, it’s time to take care of it and get your furnace back on track. We’re here to help and handle the entire process for you–it all starts with a phone call.

Contact us today to schedule your furnace repair as soon as possible.

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