The quick answer? Because they use existing heat to heat your home, rather than generate new heat. That doesn’t make much sense at first, does it? If there were enough heat in the air outside to heat your home in the winter, couldn’t you just open the window to let that heat in? Well, the fact is that heat pumpsB doB use existing heat in the air outside to warm up homes. There is a bit more to the process than that, though.
The “process” that we’re really referring to here is heat transfer, and that transfer of heat is the key to the heat pump’s efficiency. When properly installed and professionally maintained, a heat pump in Asheville, NC, can keep your home comfortable reliably while also cutting back on your heating costs. So, let’s take a closer look at what the heat pump is actually doing when it heats your home. That will help you to decide if the heat pump is the right heater for you.
Heating as the Reverse of Cooling
Stick with us on this one. A heat pump is basically just a central air conditioning system that can reverse its operation in order to heat a home, too. It accomplishes this feat by reversing its refrigerant cycle, which is accomplished with the use of a component called a reversing valve. To understand how the heat pump heats, you have to understand how they, and ACs in general, cool. (Because heat pumps can both heat and cool, remember!)
Basically, a central AC or a heat pump in its cooling mode will evaporate refrigerant in the indoor coil. This is the evaporator coil. That allows the system to draw heat out of the air in the house. Then, the refrigerant travels out to the outdoor, or “condenser,” coil. There, the refrigerant is condensed and its heat is released into the air outside.
So, What About Heating?
The reversing valve flips the function of the coils and the flow of the refrigerant in the heat pump when you want to heat your home. In this mode, the heat pump evaporates refrigerant in theB outdoorB coil, which allows it to draw heat out of the air outside. That refrigerant is then compressed in order to boost its thermal energy.
Then, the refrigerant is condensed in theB indoor coil, which allows the heat to be released in the home. That heat warms up the house. Only a small amount of electricity is used to facilitate the refrigerant cycle and heat transfer process, and the result is highly efficient heating.
Now, in instances of extreme cold, it is possible for heat pumps to be overwhelmed in their attempt to heat homes. That is not much of an issue around here, as winters are relatively mild. Also, modern heat pumps are better than ever at dealing with frigid temperatures. Even if they are overwhelmed, they can supplement the heat transfer process with electric resistance heating to get over the hump.