Most homeowners who have heat pumps use them to heat and cool their homes. But a heat pump also can be used to heat water. You may have already seen one of these units in a “big box” or appliance store and wondered what it was and how it worked. Here are the details: Heat pump water heaters use electricity to move heat instead of generating heat directly through electrical resistance. It takes a lot less electricity to transfer heat than it does to generate heat.
Therefore, heat pump water heaters can be two to three times more energy efficient than conventional electric resistance water heaters.
To move the heat, heat pump water heaters work like a refrigerator in reverse. While a refrigerator pulls heat from their interior and dumps it into the surrounding room, an air-source heat pump water heater pulls heat from the surrounding air and moves it into their internal water tank. Another type of heat pump water heater has indoor and outdoor components that move heat from outside the home. Still others are integrated with other space conditioning heat pump systems, which combine all the required equipment into a single unit located inside home.
