For years, most homes were designed with a separate furnace and A/C unit. This system worked, but required more equipment more maintenance, and potentially led to more problems. About 30-40 years ago, HVAC engineers designed the heat pump (technically, the reversible heat pump) and integrated these two systems together in the same unit.
Think of how an A/C system operates – it relies on a closed-loop cycle of compression of a gas refrigerant to a liquid state, which then evaporates again to a gas and provides cooling through that evaporation. It’s the same principle that a refrigerator or automotive A/C uses.
Heat Pumps are Sweet Simplicity
The simplicity of a heat pump design has several advantages for a homeowner:
- Many heat pumps are designed with two-speed compressors, which helps the unit adjust to the heating or cooling needs of the moment, in real-time. This means savings in electricity, more efficient operation and less wear on the compressor itself.
Two-speed compressors are especially useful in zone control systems, where it’s desirable to keep different rooms at different temperatures in a larger home.
- Some newer high-efficiency heat pumps also feature a desuperheater, which recovers heat from the unit and directs it toward a water heater. Desuperheaters can result in lower electric bills, as they can heat water two to three times more efficiently than a conventional tank-style water heater.
- A new innovation in heat pump design is the scroll compressor. Rather than using a piston for compression of refrigerant, scroll compressors have two spiral-shaped scrolls, one inside the other.
As one stays stationary, the other “orbits” off-center inside the other scroll, trapping and compressing the fluid between them into smaller and smaller pockets. Scroll compressors are quieter and more efficient, with a longer service life.
When in heating mode, heat pumps with this style of compressor can produce air that’s 10 to 15 degrees warmer than a unit with a conventional piston-type compressor.
- Heat pumps, when in heating mode, rely on extracting heat energy from outside air. When temperatures are below freezing, they’re equipped with an auxiliary electric heating element that can provide extra heat.
- Heat pumps run on electricity rather than burning any kind of fuel. In heating mode, heat pumps don’t come with any of the risks of carbon monoxide that can be associated with a gas furnace.
- An electric furnace produces roughly one unit of heat for every unit of electricity that it consumes. A heat pump is two to three times as energy efficient as an electric furnace – and newer Energy Star certified heat pumps can far outstrip even that level of performance and efficiency.
But, the Main Advantage of a Heat Pump Is…
Simplicity of design.
With only one unit that takes care of both heating and cooling needs, there’s less to install, less to maintain and less to repair when the time comes.
Why have two separate units when one heat pump can do both jobs?