All heat pumps work under a single guiding principle — they use various means to transfer latent heat from one place to another. Thanks to this principle, your heat pump not only provides cooling during the summer months but also a large degree of heating during the winter. How a heat pump moves heat around depends on the design, with some designs being more efficient and more flexible than others.
If you're looking for a new heat pump, then it's easy to become bewildered by the many choices available. The following highlights three main types of heat pumps, how they work, and their various advantages and disadvantages. Armed with this info, you'll be better prepared to choose the right heat pump system that works for your heating and cooling needs.
Air-Source: The Standard Choice for Heat Pumps
Air-source heat pumps are the most common of the available heat pump designs, thanks to their relative simplicity and affordability. The average air-source heat pump looks and functions just like the typical split HVAC system you'd normally find in most homes, except there's no separate furnace needed to deliver heat.
Air-source heat pumps come in various forms, including your standard ducted split-system and ductless mini-split forms. Ductless mini-split systems are not only energy-efficient but also ideal for homes with little space for traditional ducting thanks to their space-saving design.
The only drawback to using an air-source heat pump is its wintertime performance in very cold climates. Under extremely cold temperatures, air-source heat pumps sometimes struggle to harvest the latent heat needed to drive its heating capabilities. For this reason, air-source heat pumps often come equipped with electric or gas-powered backup heating systems to take up the slack during those times. However, backup heat consumes far more energy than the heat pump itself, resulting in reduced efficiency and increased utility costs.
Ground-Source: Efficient, But Expensive
Ground-source (or geothermal) heat pumps take a different approach toward heating and cooling. Instead of relying solely on the refrigeration process to move heat from one place to another, geothermal heat pumps harvest heat directly from the earth. Geothermal heat pumps also use a water and ethanol mixture, circulated through a ground loop of polyethylene piping, to transfer the heat.
While aboveground temperatures vary widely depending on the time of day, temperatures below ground remain constant. Geothermal heat pumps use this constancy during the winter by using the ground as a source of heat during the winter, when temperatures aboveground are cooler. During the summer, the ground acts as a heat sink, absorbing heat energy transferred from your indoor spaces.
Since geothermal heat pumps use the earth's thermal energy, you can heat and cool your home in an efficient and eco-friendly manner. Geothermal heat pumps can even provide hot water through the use of a desuperheater.
There are a couple of drawbacks to choosing a geothermal heat pump. Geothermal heat pumps aren't ideal for homes on small lots since ample space is needed to bury the ground loops required to make these systems work. Geothermal heat pumps are also the most expensive type of heat pump system to purchase and install, with total costs exceeding the $20,000 mark at times, according to HomeAdvisor.
Which Type Should You Choose?
If you're interested in the most cost-effective heating and cooling solution for your home, air-source heat pumps offer an affordable option. Air-source heat pumps are also ideal for homes that lack the yard space to accommodate a geothermal system.
On the other hand, geothermal heat pumps offer better efficiency and reduced operating costs over the long run, despite their high upfront purchase and installation costs. A geothermal heat pump will eventually pay for itself due to the reduced energy usage and corresponding savings in utility costs.
For more information on heat pumps, contact an HVAC contractor.