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McDonald Home Services Blog

This Little Sensor Could Be Causing All Your AC Problems

Your air conditioner turns on when its needs to, then stops when it doesn’t. You don’t think anything of it, except all of a sudden it’s not providing cool air. It’s not warm, but it’s not cold either, so what’s the deal? Well, it could all be due to one little sensor that’s deep in your air conditioner.

When we perform AC repair in Venice, FL, sometimes we run into a unique problem: a sensor on the blower motor. While this does need to be repaired and it’s a DIY kind of fix, the good news is that it’s not the same as a total system breakdown. As long as it’s caught early, there may also be minimal long-term damages to your air conditioner.

This is What That Sensor Does

Your air conditioner has a blower motor that’s responsible for forcing air down your ductwork. When the AC temperature treats the air, it’s then sent down the ducts to your vents. The sensor in question sits on the blower motor and acts as a resistor, which resists the flow of electricity as needed. This helps with regulatory fan speeds so it doesn’t go too fast simply because it has the capability to.

The blower motor is likely fine, but when the sensor dies out, your blower motor might be going too fast and pushing air at full speed. It sounds like it should be fine, right? But it doesn’t simply get the cool air to your vents faster. Instead, it creates a whole new problem.

The Sensor Overheats and Warms Your Air

When that sensor works too hard, it overheats and actually warms the air around it. Because there’s nothing telling it to stop going at max speed, the byproduct of operation, being heat, goes unchecked. It warms the air before it barrels down the ductwork.

Your blower motor also has something called a heat sink, which is where that byproduct of heat gets absorbed. But if the blower motor is going at full speed without stopping, that heat impacts the air around it instead. Your AC might be running constantly because you’re not hitting the target air temperature, so your thermostat hasn’t told it to stop yet.

What’s Next

This is impossible to diagnose over a blog post, so you’ll need a technician in your home to see if this is even the problem. Either way, your air conditioner isn’t doing its job, so even if we find something else that’s the problem, we can still fix it.

Don’t Wait to Get This Repaired

The longer your blower motor has to run without that sensor, the more wear and tear your AC faces. It may not even shut down at all because your thermostat isn’t getting a reading on temperature changes, so it never sends that “OFF” signal it needs to power the AC down. Don’t delay these repairs: we’re ready to help you now.

Contact us today to schedule your air conditioner repair as soon as possible.

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