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Capture AC heat for DWH

Anyone have an experience or opinion on using a heat exchanger on the AC coolent line to heat DWH. I'm looking at the DOUCETTE product for my 4 ton compressor and hooking it up to a 40 gal preheat DWH tank.



  • Tom Blackwell_2Tom Blackwell_2 Member Posts: 126
    Excellent idea

    I have used a homemade hx for domestic water preheat for over 20 years. Most of the time it provides 100% of our domestic hot water heat. The only caveat is that you must have a preheat tank rather than using the existing water heater-it's hard to add heat to already hot water. For best results use a small circulator to pump a loop through the hx and preheat tank, controlled so that it operates when the ac is in operation.
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