Atlas offers an optional desuperheater, which is a secondary heat exchanger that transfers heat from the Groundhog into your domestic hot water tank. The device provides supplemental hot water whenever the Groundhog is heating or cooling your home. The hot water circulator pump moves the cold water from the bottom of your hot water tank through a water pipe to the desuperheater itself. The water is then heated and sent back into to your hot water tank.

Heating water with a Groundhog can save up to 30 percent less in a heating dominated climate, and up to 75 percent less in a cooling dominated climate compared to a typical electric, oil, or propane fired hot water heater. At the present cost of natural gas, the savings is about 10 percent less.

In the summer, heating your domestic water is almost free. This is because the heat that is being removed from your home is transferred into your hot water tank. Since most of this heat is being sent back into the earth anyway, putting it into your hot water tank instead is free. The only cost for the summer water heating is the small cost of running the circulator pump that moves the water. Another added bonus is that heating the water helps cool the refrigerant. This allows the compressor to use less electricity, which usually off sets the cost of running the circulator pump.