Thermostat Troubleshooting Tips

Posted: 2019-05-30

Your HVAC system’s thermostat may be a small device that is frequently neglected, but if it’s not working, it can cause you great inconvenience. The upside: thermostat problems are not as expensive as other air conditioner or furnace issues. In fact, there are a number of things that can disrupt a thermostat’s function that can be corrected with simple troubleshooting steps.

Four Seasons Air Specialists is your friendly HVAC company in Lino Lakes MN that can fix any HVAC equipment, including thermostats.


A thermostat is a device that controls the temperature in an HVAC system like a furnace or an air conditioner. You can set a predetermined temperature, and the thermostat works to keep your room at your desired level. When your furnace or air conditioner reaches your set temperature, the thermostat will turn the system off to prevent it from overheating.

When your home suddenly has no heat or cooling, the problem could be your thermostat, rather than the main HVAC system. Understand that not every thermostat issue requires professional help. Actually, there are things you can do on your own before calling an HVAC technician.

Here are some helpful tips on how to deal with a faulty thermostat.

Check the power.

Is your thermostat powering on and off by itself? The first thing you need to check is whether or not it is getting enough power. Most thermostats receive power from batteries, so you’d want to make sure it has fresh batteries installed. Also, check for tripped circuit breakers, which can cause your system to lose its power. Once you’ve concluded that everything is fine with your power source, try turning the system back on.

Check your settings.

Thermostat switches can be accidentally moved to the wrong setting, so be sure to check the thermostat is set to “HEAT”. If you have a programmable unit, make sure it is set properly for your preferred temperature at the specific time of day.

Check your thermostat’s position.

You may not be aware, but your thermostat needs to be mounted properly on the wall in order to get proper temperature readings. Make sure it is not positioned near any heat sources like direct sunlight, gas stoves or refrigerators. Also, keep your thermostat away from vents, registers, and windows as these can affect the temperature around the thermostat.

In addition, try checking if the thermostat is balanced. Using a level device, make sure your unit is perfectly level on the wall. If it isn’t, then, your mercury switch won’t work accurately.

Check for dirt buildup.

Any HVAC system can experience problems whenever it has accumulated dirt — and your thermostat is no exception. Too much dirt can cause inconsistencies between your temperature settings and the actual room temperature. In such cases, your thermostat needs a good cleaning.

If you have an older electromagnetic unit, simple brushing can solve the problem. Gently dust off the inside of your thermostat, together with the metal coils and contact plates. If your brush is too large and can’t fit within the plates, try sliding a soft paper back and forth to wipe them off.

Check for compatibility.

In order to work with your existing heating or cooling systems, your thermostat should be compatible with them, especially if your HVAC unit has advanced features such as variable-speed operation. If you have a heat pump for both heating and cooling, make sure the thermostat and your heat pump are compatible.

Check your thermostat’s wiring.

Sometimes, wiring issues can cause your thermostat to malfunction. Check the thermostat’s wiring connection by removing the casing and back plate. If it’s a new thermostat, check the wiring diagram.

A word of caution though: avoid getting in trouble by not playing with wiring issues. There are some who think that they can fix a broken thermostat by moving some wires without considering the possibility of burning the control boards or worse, the transformer. Unless you have proper HVAC training, you should leave serious wiring issues to qualified technicians only.

Still Having Problems? Call the Experts

These simple troubleshooting tips should help you restore your home’s comfort. However, if you are experiencing more serious thermostat issues, do not hesitate to call Four Seasons Air Specialists, your trusted Centerville heating and air conditioning company.