The Heat Pump—An Energy Efficient Heating and Cooling Option

What’s cool during the summer, warm during the winter, and environmentally friendly throughout the year? A heat pump!

Heat pumps (also referred to as ductless or cold-climate heat pumps, or mini-splits) can be an energy-efficient home heating solution, depending on the layout and building envelope of your home and the heating systems you already have in place. And they double as an air conditioner in the summer. What could be better than that?

WHAT IS IT?

A heat pump is a heating and cooling unit that uses electricity very efficiently to extract heat from the indoor or outdoor environment using a compressor. As its other name (mini-split) suggests, the system is “split” into two parts—the compressor, which is installed outside; and a register, also called a ‘head,’ which is mounted on an internal wall.

The mini-split extracts heat from the outdoors to warm your home and, when it is hot outside, can be used to remove heat from your home. Think of how a refrigerator works, extracting warm air from inside to outside using a compressor. Same idea with a heat pump, in reverse, extracting warmth from the outside air to be moved indoors.

Extracting warm air from the outdoors in winter may sound strange, but that’s exactly what the compressor does. It is able to pull heat from air, even at freezing temperatures (though they become less effective on sub-zero days).

A FEW IRRESISTIBLE BENEFITS

Because they move air, rather than generate it, mini-splits use relatively little electricity to heat or cool your home. Therefore, they’re a more environmentally friendly option than fuel-based heating systems, especially if you decide to add solar PV to your home and use the power of the sun to generate the electricity that your mini-splits use. And the fact that they rely on electricity, rather than oil or gas, means that you don’t have to worry about carbon monoxide, arranging for fuel deliveries, or running out of fuel.

These compact heaters are more efficient than central air units because, unlike most heating systems, they maintain a stable temperature over time. Most heating systems wait for the room temperature to reach a predetermined low before turning on and running full blast to reach the desired temperature. Mini-splits produce heat consistently and economically, which means your space maintains a comfortable temperature.

Plus, operation and maintenance are easy. Most installers agree that it’s best to set up your thermostat for the season, and just ‘set it and forget it’ so the unit is most effective. There are air filters that are easy to clean and the outside compressor just needs an inspection and a light brushing to remove any leaves or other debris.

And finally, these aren’t just heaters. They also cool your home in the summer. In a climate where winters are freezing and summers can be hot and humid, these dual benefits can be compelling.

IS THIS THE HEATING OPTION FOR YOU?

As noted in the first paragraph, heat pumps can be ideal for heating your home, but how ideal they are for you depends on a few things. Before you buy, consider the following:

• Depending on your situation, these units may be an affordable option, so you should consider if the long-term benefits outweigh the upfront installation cost. Equipment costs depend on the system size and type, but a single head, installed, can cost between $2,000 and $6,000.
• This is not typically a DYI project, as the unit contains refrigerant and needs to be charged and pressurized before use, and there’s some electrical work that should be done by a professional. However, price points vary, and rebates and low-interest financing can make them an affordable option.
• The most significant consideration regarding this option is appropriate application. They are not considered a primary heating system, so if you have a smaller, open concept, weatherized home, they work like a miracle; if you have a home that is divided into many small rooms, or is leaky because it hasn’t been weatherized, this heating solution may not be ideal.

If you are considering heat pumps for your home, you may want to start with an energy efficiency professional who can perform an energy audit, discuss your goals, and evaluate if they are a good option for your situation.

BEFORE YOU BUY

If you’re thinking of investing in a heat pump, take a good look at the layout and efficiency of your home and the current heating systems you have in place to make sure it’s a good fit. Efficiency Vermont can be a great no-cost resource for helping you determine whether it will help you achieve your energy efficiency and home heating goals—they can put you in touch with a certified heat pump contractor from their Efficiency Excellence Network for a free evaluation.