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Heat Pump Water Heater in Mechanical Room

I have a project with significant waste heat in a very large mechanical room. I would like to reclaim the heat and am considering a HP water heater for domestics as an option. Are there any systems out there with ducted exhaust?


  • Brad White
    Brad White Member Posts: 2,393
    Is the waste heat in the air?

    If it is a warm and even humid room otherwise, there is a product, name escapes me. This device is an AC unit/dehumidifier which sits atop the DHW heater and uses the hot gas waste heat from the refrigerant process to pre-heat the DHW incoming cold water. (Rather uses the incoming CW as a water-cooled condensing medium).

    If I come across the name I will post it but others I am sure know the one I am talking about.

    There also were a line of Free-heaters from Spiro (the spirovent people) and Meuller refrigeration specialties, to take the same hot gas waste heat from commercial refrigeration and use it also to pre-heat incoming CW to DHW systems. We specify the Meuller line on commercial kitchens but I see no reason it cannot be adapted to other AC processes. 

    Depending on how hot the room is, a more passive coil situation could be used, but the refrigerant boost is more positive.

    How hot IS this room?  It may be as hot as my grandfather used to say: "Hot as a June Bride in a Feather-Bed". Now that, my friend, is hot. :)
    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"

    -Ernie White, my Dad
  • Steve_210
    Steve_210 Member Posts: 594
    A O smith

    Make a unit like what brad mentioned. Just seen it at a show
  • TMorg
    TMorg Member Posts: 23
    HP water heater

    Rheem/ Ruud makes a really nice unit.
  • Steamhead
    Steamhead Member Posts: 14,840
    I think

    it's called a "desuperheater". 
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
This discussion has been closed.