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I am looking for a heat pump that can be added to a water heater

jsimon1 | Posted in Green Products and Materials on

I am looking for a heat pump that can be added to a water heater. I saw it on a program of This Old House in Jan 2014.

I was given this web site while looking on the internet.

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  1. GBA Editor
    Martin Holladay | | #1

    It sounds like you are talking about the Geyser heat-pump water heater -- a type of heat-pump water heater that comes without a tank. It is designed to be hooked up to an existing water heater.

    For more information on the Geyser heat-pump water heater, see these three articles:

    Geyser Heat-Pump Water Heater

    Getting Into Hot Water — Part 2

    Getting Into Hot Water — Part 4

    For a general overview of heat-pump water heaters, see Heat-Pump Water Heaters Come of Age.

  2. Expert Member
    Dana Dorsett | | #2

    There's also the AirTap A7 retrofit for electric HW heaters:

    It's been out there for at least 5 years now, with an installed base of well over 10,000 units, if their marketeers are to be believed. They also has vent-kits available if you want to duct the cool airstream somewhere other than the room where the water heater is located. (That's a feature of their fully integrated Ati-xx hot water heaters too.)

    The blue box store carries them retail for about $750 in some markets, but they can sometimes be had for less from internet sources.

  3. GBA Editor
    Martin Holladay | | #3

    Thanks for the reminder about the AirTap. Here are two GBA articles that mention the AirTap:

    AirTap Heat Pump Module

    Heat-Pump Water Heaters

  4. PAUL KUENN | | #4

    We've had our AirTap for three years now and it is flawless. Make sure you're not going to overuse it. I originally added it to a heavy use 80 gallon tank and it could not keep up with demand and would frost up, even with the additional resistive heater coil. On our 50 gallon domestic tank it works perfectly. When it's cloudy and our solar thermal collection is down (70-80F degree water left in the tank), it will heat the water to 128F in about an hour and use about 750 watts. We wrapped our standard glass lined tank with R30 fiberglass and have it sitting on top of 4" of EPS to keep it cozy.

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