How Your Home Works: All About HVAC Heat Pumps
One of the most important components of any heating system is the heat pump, which acts like the “lungs” of the entire HVAC system. It draws in cold air, pushes heat out, and creates a comfortable temperature for you to live in. Here’s what you need to know about these systems.
What Is It?
A heat pump is a device that actually heats and cools a space, usually a residential or commercial building. But when you hear the word “heat,” you might initially think of a heater.
A heat pump is a device that uses a small amount of energy to move heat from place to another – usually from either the air or ground into a building.
Heat pumps pull air from outside inside. When cooling is needed, then refrigerant cools the air before a fan blows the air indoors.
One of the biggest advantages newer heat pumps have over traditional HVAC units is that there’s no need for a separate furnace and air conditioner. The unit is one unit and does both. They’re also more energy efficient, since they move existing heat, rather than burn fuel to create it.
They work best in moderate climates where the temperatures never swing to extremes, so if you live in an area where the seasons are fairly constant, a heat pump may be able to help you put a little coin back in your purse while keeping you warm in the winter and cool in the summer.
Types Of Heat Pumps
A reputable company will sell several types of HVAC products. But, the main types of heat pumps on the market are “air-source,” “ground-source,” and “absorption” heat pumps. Air-source heat pumps use an outdoor fan to bring in outside air and move it over coils filled with refrigerant.
There are two sets of such coils that transfer heat indoors. From there, it’s blown off the coils by a secondary fan and then distributed through your home as cold air.
Ground source pumps absorb heat from the ground or an underground body of water. They then transfer it indoors and from there the secondary fan provides the cold air.
Finally, an absorption heat pump is powered by natural gas, solar power, propane, or geothermal heated water rather than by direct electrical current.
Absorption pumps can be used for large-scale cooling applications, but they can also be used in residential. The main difference between the absorption and air-source (or ground-source) pump is that there is no compression of refrigerant. Instead, the absorption pump absorbs ammonia into water and then a low-power pump pressurizes it.
From there, the heat source boils the ammonia out of the water, and the cycle repeats.
Other Types Of Heat Pumps
Two uncommon types of pumps include the mini-split heat pump and the reverse cycle chiller. The mini-split heat pump connects an air-source unit to multiple indoor units. These indoor units then connect to water heat or space heaters.
A reverse chiller heats and cools water, rather than air and operates in below-freezing temperatures.
Katherine Taylor works as an energy auditor. He enjoys writing about his experiences online. His articles can be found on many DIY and home improvement sites.