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Community and Q&A

Using heat from Fridge to heat water

dmdvt | Posted in Green Products and Materials on

Has anyone thought about using the heat pump in the fridge to heat hot water?
What about a hack from a DIY ?

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  1. GBA Editor
    Martin Holladay | | #1

    There are several comments posted on this blog page that discuss the idea: First comment discussing refrigerator-cum-water-heater idea.

    There are several problems, including these:
    1. The two loads aren't matched in size.
    2. The two loads aren't necessarily simultaneous.
    3. Most homes can't accommodate a single large appliance that acts as a refrigerator-cum-water-heater because of the size of the appliance.
    4. Combination appliances are a pain because when one part fails, both appliances fail.

  2. user-1094014 | | #2

    I think that's a great way to increase the efficiency of the refrigerator and recapture the energy for use any time of year. the heat fro a frige is not wanted during the heating season, but in the non-heating season it could be put to better use. i agree that the loads are not balanced or necessarily required at the same time, but, you could use a secondary tank as the heat exchange reservoir that could be more easily balanced and use it as a cold water preheater for your domestic water heater. that way the recaptured energy is useful all year. just a thought.

  3. user-939142 | | #3

    it is also a sales nightmare to try and push two separate products at one time; that will always be the real barrier - nobody will buy it.

    and we would need to do a return on investment on such a device to see if the extra costs could be recouped. this wouldn't be the first 'use something relatively free' like say venting your fridge/freezer to the outside during the cold of winter or recovering waste heat in the shower where the solution costs more than any savings.

  4. user-669103 | | #4

    About the only cheap and easy use for that low grade heat from the back of the fridge is an "airing cupboard".
    Basically building the airing cupboard with a fridge size hole on one size.
    I haven't tried it or seen it tried. Just an idea.

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