How Does Your Thermostat Work?

Thermostats aren’t often a device that you think about. If you own an HVAC unit then you own a thermostat, but you may have never thought about the impact it has on your comfort.

The thermostat measures the temperature in your house and tells the AC unit that it needs to turn on or off, either heating or cooling your house. When you buy a home you inherit the previous owner’s thermostat, and depending on its age, replacing it could save you quite a bit of money.

Electromechanical Thermostats vs. Electronic Thermostats

Thermostats have changed over the years and depending on the age of your home, your thermostat probably comes in one of two forms: Electromechanical or Electronic.

Electromechanical Thermostats

Electromechanical thermostats are older and operate on fairly simple principles. Inside the thermostat is a coil of metal that expands or contracts with changes in temperature. As it expands or contracts, the metal makes contact with electrical contacts that send a message to the AC Unit – either to heat the home or cool it down.

Some older electromechanical thermostats may actually have mercury thermometers in them to help control the temperature. Recycling these units can be tricky and dangerous. If your thermostat has mercury, make sure that you properly recycle it.

Check For Dirt and Residue Build-up

One major problem with electromechanical thermostats is that they are delicate and susceptible to error. The metal coil that controls the AC Unit can get dirty or residue build-up and that can lead to your thermostat not registering the proper temperature. If your AC unit is always running, or won’t turn on, it could be a sign that your thermostat is faulty.

Electronic Thermostats

Electronic thermostats are more modern and tend to be more reliable than electromechanical thermostats. Thermostats today are highly programmable and function like a small computer. They calculate the temperature using a device called a thermistor. The thermistor is a special resistor that measures the flow of electricity dependent on the temperature. The higher the temperature, the more resistance the thermistor creates, telling the thermostat to turn on the thermostat.

A Good Thermostat Can Be Crucial to Your Home Running Efficiently

Today’s thermostats are highly programmable and can help you from running your air conditioning when you don’t need it. You can set temperatures for while you are at work, when your home, when you sleep, weekends vs. weekdays. All these features keep you from cooling your house when you don’t need it.

Modern thermostats can now be controlled by your cell phone. By linking your thermostat to the internet, you can now check the temperature of your house at any time. Properly programming your thermostat can keep your energy bill low and save you money.

If you think it’s time for an upgrade, give us a call and we can walk you through your options.