What does it mean when your thermostat is not working? A home thermostat is the control device for your AC and heating. It uses temperature sensors, and wiring leads to both know the current temperature in your house and then run the AC, fan, or heat until your set temperature is reached. At least, that is what it should do.

A thermostat not working means some part of that system isn’t operating properly. The question is: What? It could be the sensors, the wiring, the power, the installation, or even the placement. Before considering buying a new thermostat, let our skilled technicians at Superstition Cooling help you troubleshoot whether your current thermostat errors can be fixed.

Error #1: The Room is Not Reaching the Set Temperature

One of the first signs that you have AC problems is if your house never quite reaches the temperature you set. What is frustrating, however, is if your thermostat is wrong. If your thermostat says your room temperature is at 72, but you have a separate thermometer that reads 81, or you set it to 65, but you have proof the room is 58, this is a thermostat problem.

Determining that your thermostat is not working is the first step to solving the problem – and will be a lot less costly than a problem with your AC. Several things can cause a thermostat failure, but these are the most common.

Sensors are Broken or Damaged: The fact is that your thermostat’s sensors aren’t working. The first possibility is that they are damaged or broken. The more wrong your thermostat is, the more likely your sensors are fully damaged. If your thermostat is a little wrong all the time, the problem could lie elsewhere.
Poor Thermostat Location: Your thermostat needs to be in a central location representing the whole house’s temperature. If it is near a heater, a vent, a fireplace, or a cold window, your thermostat may constantly read the home’s temperature wrong, hot or cold.
Dirty Equipment: The easiest to fix, however, is if the equipment is dirty. If the internal components of your thermostat have become dusty or dirty, it may be getting an incorrect read. Try opening and gently wiping down the inside of your thermostat, including the pins, before running it again.
Corroded Thermostat Components: A bigger problem, but often still solvable, is a small amount of corrosion on your thermostat sensors or the pins that connect the faceplate to the AC system. You can use a special electronic contact cleaner to remove light corrosion on the components.
Poor Installation: Another potential issue is that your thermostat was installed incorrectly. As a result of poor installation, a component could be misaligned, have poor placement, a shaky sensor connection, or another flaw in the thermostat’s installment, causing an inability to get an accurate reading.
Improper Calibration: It is also possible that your thermostat was just improperly calibrated and is wrong about the temperature though everything else is working correctly. An HVAC technician from Superstition Cooling will typically be able to recalibrate your thermostat to see if this solves the problem.

Error #2: Thermostat Won’t Change Temperature

If your thermostat issue is that it won’t change settings, no matter how many times you cycle the power or press the button, there are a few different causes for this problem.

The Setting is Locked: The most likely is that someone locked the thermostat. Most thermostats can be locked to prevent others from changing the temperature without permission or by accident. Check the thermostat menu to see if you can turn off the locked mode and change the temperature setting.
Set to Auto Mode: Some thermostats have an “auto” mode that is neither heat nor cool. This setting may be the case when you find an AC thermostat not working because it won’t acknowledge the temperature change buttons. Change the mode, and try again.
Device Malfunction: If your thermostat is not acknowledging a change in settings but is still running, it could be a device malfunction in the computer components of the thermostat instead.

Error#3: Thermostat Won’t Turn On

If your thermostat is not responding or won’t turn on, or won’t turn off, the issue may be a steady supply of power rather than an issue with the settings or sensors.

No Power: For a thermostat that won’t turn on or the screen is extremely faded, check the power. If your thermostat is battery-powered, remove the faceplate and change the batteries. Otherwise, there may be a power issue with your AC circuit inside the wall.
Loose Wiring: If the symptoms of your thermostat not working are irregular, the issue could be loose wiring. This issue can cause things like the control panel or sensors to work at some times but not others.
Troubleshooting a Thermostat: The key to troubleshooting a thermostat is to try different settings and solutions. Check the settings and double-check the temp with an external thermometer. Change the batteries, check the wiring, and gently clean the contacts. If that doesn’t work, Superstition Cooling can help you with a thermostat installation, replacement of corroded elements, faulty wiring, or a thermostat replacement.

Professional Air Conditioning Repair & Maintenance Services in Apache Junction

Sometimes a simple fix ends up being a more complex issue. Don’t let a faulty thermostat keep you from enjoying the perfect temperature in your home. With years of experience, our team of HVAC technicians at Superstition Cooling has seen it all when it comes to thermostat problems.
Don’t let a faulty thermostat keep you from enjoying the perfect temperature in your home. Take action today and let Superstition Cooling help you get your thermostat back on track!

Image Credit / Shutterstock / Steve Cukrov