How to Clean Your Thermostat at Home

Would you like to know how to clean your thermostat? A dirty thermostat can create many problems in an HVAC system’s performance. You could think that the thermostat is broken when an excellent clean-up is only necessary to make it work properly.

The good news is that it is possible to clean the thermostat without a professional intervention in a few simple steps. But if you can’t manage to get it done, or if complications arise, Hurliman Heating can help you.

Why a thermostat need cleaning?

Thermostats can malfunction when the dirt is cumulating between their components. The dust cumulates, preventing the thermostat from calibrating correctly and thus consuming more energy than necessary to perform its functions.

Cleaning is even more critical for electromechanical thermostats since they have internal moving parts. Dirt build-ups prevent those parts from doing their job, resulting in a faulty thermostat.

Periodic cleaning is a way to ensure that the thermostat can set the temperature correctly and maintain the temperature you want. Another good reason to clean the thermostat periodically is to prevent higher energy consumption.

Dirty thermostats can significantly increase your utility expenses. In addition, the longer the situation lasts, the more will be spent on energy bills.

Which components of a thermostat need to be cleaned?

Depending on your thermostat, you can see various components such as the bimetal coil, wires, a contact point (sometimes contacts are controlled by a glass vial filled with mercury), and a heat anticipator.

The parts that need the most cleaning are the coils and the contact points since they are responsible for the correct temperature reading of the thermostat.

In addition, the anticipator needs to be adequately cleaned to prevent an increase in energy consumption.

If you have a digital or a smart thermostat, it is not necessary to do an internal cleaning, but it is a good habit to clean at least the surface.

How to clean the thermostat

Cleaning the thermostat is not tricky. It requires time and patients. In general, the steps to follow for cleaning a thermostat are the following:

  • Turn the power off
  • Remove the cover
  • Dust the inner thermostat components
  • Check if there are broken parts or damaged wires
  • Replace the batteries if necessary
  • Clean the cover
  • Put the cover back on

The materials required to clean the thermostat are a soft brush, a cotton stud, and a small piece of paper. It can be done by anyone, even without experience. However, it can also be done through the yearly maintenance service by qualified technicians.

Turned off the power

It is essential to switch off the power as a precautionary measure. The thermostat is composed of wires, and attempting to clean them while the electricity is still running can be dangerous for you and damage the system.

Remove the cover

Depending on the thermostat you have, removing the cover can be as easy as snapping it, or it might be necessary to use a screwdriver to remove the screws and lift the cover.

Clean the contact points

The first thing to do is to increase the temperature of the modulator, then with a piece of paper, clean the between the contacts. Next, it is necessary to lower the temperature in the modulator until the contacts close again and repeat the cleaning with a small piece of paper.

Finally, using a compressed air duster, remove all the dirt.

Dust the bimetal coil

Using a soft brush, remove the accumulation of dust and dirt from the bimetal coil and the heater anticipator. Using a compressor air duster, remove the leftover dirt.

Clean the switch contacts

The switch contacts should also be cleaned with a cotton bud, better if wet.

Clean the cover and put it back on

There are more things to inspect before you put back the cover. First, you should check if the batteries need to be replaced with new ones. Then inspect the wires for signs of corrosion.

If there is a problem with the wires, it is necessary to call a technician.

A professional can inspect, determine what is wrong, and eventually fix the issue.

At this point, if everything is fine, clean the cover and put it back on. Next, turn on the electricity and test the thermostat to verify that everything works fine.

What are the most common issues in a thermostat ?

Your thermostat can experience several issues over time. The most common are:

  • Broken sensors
  • Wrong location
  • Corrosion
  • Wrong installation
  • Loose wiring
  • Dirty components

Dirty components in a thermostat are not the only reasons for malfunctions. For example, broken sensors are responsible for the thermostat failing to reach the desired temperature because the temperature reading is wrong.

The wrong location can lead to issues with the temperature. For example, if the thermostat is near a fireplace or in direct sunlight, it can send false signals to the HVAC system, which will make the house too hot or too cold.

Loose wires could be responsible for the lack of power getting to the thermostat. In this case, it will not work, and the HVAC system will not run. On the other hand, the wires may be just subject to corrosion, as are the electrical components.

If the thermostat is old, it is common for electrical components to deteriorate. In this case, they need to be replaced, or the thermostat needs to be replaced. Another common problem is the thermostat not level.

When it is not level, the mercury bulb inside the thermostat will not work correctly, causing it to be inefficient. As a result, it will not be able to detect the house temperature and will send the wrong signals to the HVAC system.


Dirty thermostats can cause many problems with the house temperature and can make the HVAC system overwork. However, cleaning a thermostat is not difficult and can be done by anyone, even those with little experience. Through the cleaning, it is possible to detect other problems with the thermostats and their electrical components and take the necessary action to repair them.

Leave a Comment

Your email address will not be published.