Most people know at least a little bit about furnaces and air conditioners, and how they work. People tend to be less familiar with heat pumps, though. What are they? How do they work? And why would you choose one for your home?
What they are
A heat pump is an HVAC system that supplies both the heating and cooling for your house, and can do so more efficiently than most furnaces or air conditioners.
How they work
Though the “heat” in their name might make people equate them with furnaces, heat pumps are actually very similar to air conditioners. An air conditioning system consists of two radiator-like coils; one absorbs heat inside the home, and the other releases that heat to the outdoor air. And that is exactly how a heat pump works during the summer. The big thing that sets it apart from an air conditioner is that a heat pump can be reversed, so that it absorbs heat with the outdoor coil and releases that heat through the indoor coil.
Air-source vs. geothermal
There are two main types of heat pump systems. Air-source systems are the most common, and are so named because they use the outside air as their source of heat in the winter. Geothermal systems use the ground as their heat source. Though more efficient, geothermal systems do cost more to install than air-source models.
The primary benefit is that they are very energy efficient. A furnace can never provide more heat energy than it consumes in fuel energy; it cannot surpass 100 percent efficiency. Since a heat pump does not produce heat, but merely pumps refrigerant, it can provide more energy than it consumes. Up to 300 percent efficiency is not uncommon.
Heat pumps also only require one system, instead of having a separate air conditioner and furnace, and they tend to last longer than other types of HVAC systems.