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Thermostats are an integral part of every home heating and cooling system. We know what they do, but do we know how they do it? At JW Plumbing, Heating and Air, we’ve been proud to serve the greater Los Angeles area for almost 15 years when it comes to providing high-quality air conditioner and heating services. We’ve put together this handy guide to tell you all you need to know about how exactly your thermostat works.

What Is the Difference Between a Thermostat and a Thermometer?

Where a thermometer is used to simply measure the temperature of a room, a thermostat is used to control the temperature of a room. You will set the desired temperature, and the thermostat will detect how warm or cool the air is and then make small increases and decreases to it in order to keep the temperature regulated.

How Do They Work?

The science behind the thermostat is pretty simple. As things heat up, they expand, and as things cool down, they contract. This is known as thermal expansion, and mechanical thermostats will use this to switch on and off an electrical circuit. You’ll commonly find bimetallic strips and gas-filled bellows in most thermostats.

A bimetallic strip is the name given to two pieces of metal, both different metals, bolted together. The bimetallic strip forms something of a bridge within the electrical circuit that’s attached to your home’s heating system.

When this bridge is “down,” the electricity will be flowing throughout the circuit and the heating will be on. As the house warms, so will the strip, and as one of the metals expands more than the other, the strip will begin to bend ever so slightly. Eventually, it will have bent enough that it has opened the circuit, and the bridge will be “up.” When this happens, the electricity will switch off and cut the heat, cooling the room.

As you may have guessed, the strip will begin to cool again, and eventually, it will snap back into place, allowing the heating to turn back on. With a temperature dial, you’ll be able to change the temperature that causes the circuit to switch itself on and off.

It’s important to note that cranking up the thermostat won’t make your home warmer or cooler any faster; it simply tells the heating or cooling system when to turn on.

JW Plumbing, Heating and Air is an award-winning company that has been providing dependable air conditioner and heating services to Los Angeles and the surrounding area for almost 15 years. Is your thermostat not working as it should? Give us a call today for cost-effective heating and cooling repair, maintenance, and installation services.