You might be tempted to think about heat pumps as “new” technology. They’re not. The concept of a heat pump was actually described in 1852 by Lord Kelvin, and even that was a refinement of a demonstration of artificial refrigeration – one that took place in 1748! Robert C. Webber developed the idea (and a working prototype) for a ground source heat pump in the late 1940’s, with a little help from his water heater and an accidental encounter with the business end of his freezer. (He burned himself by touching the freezer’s refrigeration line – which was hot!) After re-routing the refrigerant line through his water heater as a test, he built a full-sized heat pump that served his entire home.
There are many different heat pump designs, but they all do the same basic thing – they move heat from one place to another using refrigerants. Although they may have operated on the same basic principles, those basic heat pumps are a far cry from today’s air-source heat pumps. If you have dismissed heat pumps as being too expensive to operate, or not robust enough to make it through a Boston winter, keep reading.
In very basic terms, a heat pump is an air conditioner that operates in reverse, generating heat instead of cool air. A mini-split or ductless system is a reversible system, so it can generate both hot and cold air. When refrigerants are compressed, they heat up. When they’re expanded, they get very cold. By circulating uncompressed (cold) gases, the system can make the refrigerants “absorb” heat. When the system forces the gas to expand, the refrigerant dumps heat.
Early heat pumps used the ground as a heat source, so refrigerant loops were buried in the ground around a house or building. Advances in technology have made air-source heat pumps more efficient and less expensive to install and operate. Today’s heat pumps aren’t like heat pumps that were installed even 10 years ago. New refrigerants are exceptionally efficient because they can compress and decompress much better than older refrigerants. This “supercompression” allows the refrigerants to absorb and transport heat from the air much more readily than ever before.
As an added bonus, air-source heat pumps (think mini-split ductless systems) can operate in both directions. The refrigerant flow is reversible, so when the refrigerant moves in one direction, it delivers heat into a home. Reverse the flow of refrigerant and the refrigerant will absorb heat from the home and dissipate it outdoors.
Air-source heat pumps are electric, so when you install one, your electric bill will rise, but because air source heat pumps are so efficient, the rise in your electric bill will offset the cost of heating your home using another fuel. As an added advantage, you get both heating and cooling in one package without the need to install ductwork – a major source of inefficiency. They’re also incredibly quiet. When they’re operating, the indoor units are acoustically no louder than a whisper.
If you’d like more information about using an air-source heat pump or a ductless mini-split heating and cooling system, please give us a call at Boston Standard Plumbing & Heating at (617) 288-2911 anytime. We can schedule a visit and show you how an air-source heat pump can heat and cool your home.
Photo Credit: Stig-Espen Soleng, via FreeImages.com