How Does a Heat Pump Work?

How the heck does a heat pump work, is usually the question that is on everyones minds when they first hear about this amazing devices that can transfer heat from outside your home in the winter time to the indoors and keep your home comfortable.

To explain this we’re going to use the concept of a regular window air conditioner unit to explain. You see a heat pump, whether it’s a ductless or ducted system, is doing the reverse of what an air conditioner does in the summer time.

An air conditioner takes the heat from inside your home and extracts it to the outdoors. A heat pump in the winter time extracts heat from outside your home and moves it to the inside.

This is where the term “heat pump” comes from. These devices don’t actually create any heat they simply transfer it from one place to another.

How does a Heat Pump Extract Heat in the Winter Time?

This is going to take a bit of science babble to fully explain, so sit tight we’ll get through this together.

Your heat pump systems contains a refrigerant, such as freon. This is the key to how a heat pump transfers heat even with sub zero temperatures outdoors.

The refrigerant in your heat pump systems starts out very cold in a liquid form. When the refrigerant is in a liquid form it is colder than the outside air temperature.

Liquid refrigerant moves through the evaporator coil of the outdoor unit which forces outdoor air over it. Because the liquid refrigerant is colder than the air heat is absorbed and extracted from the air. This begins to warm up the liquified gas in the heat pump system. As the gas heats up the liquid begins to transfer back to a gas state.

After it leaves the evaporator enters the compressor unit which mechanically compresses the gas and increases the temperature even more.

The hot gas then moves from the compressor to the indoor condenser unit. There a fan moves interior air over the hot gas which extracts the heat effectively and blows it into your room. This process cools the gas down.

From the interior condenser the gas moves to a metering device that cools it even further. After this point the the gas is converted back into a liquid and the process starts over again by extracting more heat from the outdoors and transferring it to the inside of your home.

It sounds like it’s just a few steps, but the process is constantly happening when your heat pump is running.

There is a point where it becomes too cold outdoors and the gas inside your heat pump system can no longer absorb heat from the outdoor air. In Nova Scotia this doesn’t happen very often, but when it does a backup heating system is required.

To learn more about heat pumps or to receive a risk free estimate to install a ducted or ductless mini split heat pump in your home please call Sunshine Renewable Energy today or request a free in-home assessment on the top right of this page.