AC Thermostat Complete Guide & FAQs

Does your thermostat seem to fail to work? If so, here are a few things you can do prior to reaching out to an expert technician. Sometimes, the fix is as simple as changing a battery or replacing a fuse.

Regardless of the problem, our troubleshooting guide will help you identify the fault and fix it yourself whenever possible.

What Is The Main Role Of A Thermostat In AC?

The thermostat is one of the key elements of any AC system, as it allows the control of the air temperature. The thermostat uses a sensor to measure the air temperature and switches the unit on and off to maintain the previously set temperature value.

All air conditioner units on the market feature a thermostat to help to regulate the room temperature. The thermostat can be either manual or automatic.

Where To Look For The Thermostat In My AC Unit?

Check out the control panel of your indoor unit, and you’ll find the thermostat just behind it. To access the thermostat, you must remove the grille and the control panel. The thermostat should also feature a temperature sensor, which is actually the critical element that enables the temperature regulation process.

How To Know The AC Thermostat Is Broken?

AC Not Starting

Should your AC unit fail to turn on, you can suspect a faulty thermostat. As a matter of fact, a system that doesn’t start or doesn’t respond to any commands is a surefire sign of a bad thermostat.

Put it this way: when driving a car, you use the accelerator and the brakes to control it. If the vehicle doesn’t respond to these commands, there’s a problem with these systems more often than not. Similarly, an AC unit that fails to respond to your commands is probably a telltale sign of a failing thermostat.

AC Not Responding To Settings Or Other Commands

If the thermostat seems to fail to react to any of your commands, you can be positive it is broken. Pay attention to the sounds of your AC unit when you make changes, as the thermostat should produce a clicking sound as you make these changes. If you don’t hear any clicking sounds, chances are you must replace your thermostat.

Why Is My Thermostat Failing To Work?

Many things may prevent a thermostat from working. One of the most common culprits is a lack of power (which can emerge because of a blown fuse, dead battery, or tripped breaker). If you’re positive that there’s no problem with the power, you should disconnect the unit from the power to examine it. Never remove the control panel without unplugging the AC unit from the mains, as you risk electrocuting yourself.

Is There a Way To Check The AC Thermostat?

Listening to your AC unit while adjusting the temperature is the easiest and the most effective way to check the thermostat. You may want to ask someone else to help you perform this check and listen to the clicking sounds of the thermostat while you’re changing the temperature settings on your remote. If there’s no sound coming from the system, chances are the connection between the unit and the thermostat is broken.

Can I Replace the Thermostat Without The Help Of A Professional?

Yes, you surely can do this by yourself, provided that you know how to proceed. This is a great way to save money. Nonetheless, for safety reasons, you must have a good understanding of electrical systems in general, of the tools required to do the job in the safest manner possible, as well as of the right type of thermostat for your AC system.

Should you attempt to replace a faulty thermostat without knowing about these things, you risk causing even bigger damage to your unit or even severely injuring yourself. In such situations, you’d better seek expert help to fix your broken AC system.


Fixing a broken AC thermostat requires that you know how such systems work. In the above guide, we have shown you how to troubleshoot and repair your AC thermostat without the need for hiring an expert technician to help you. If you aren’t sure you can do this yourself, consider reaching out to us for assistance. We are fully qualified and willing to help you fix your AC system as quickly as possible!

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