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Energy Conservation Unit

The heat exchanger connects to the heat pump compressor discharge line and the water storage is circulated from the heat exchanger to the storage tank. Works well on SEER 10 unit BUT I am told not so well on Newer SEER 14 unit?


  • John G_4
    John G_4 Member Posts: 5
    ECU with hi SEER A/C unit?

    What is your thoughts on re-hooking up an Energy Conservation unit for hot water on a new Hi SEER unit? Getting different answers from down south. Some say it is not worth it because of the SEER rating. SEER 14
  • C.Beck
    C.Beck Member Posts: 1
    Chiller theory?

    What is the basic theory behind chiller system heating and cooling and basic system layout?? Is it similar to geothermal piping?
  • John G_4
    John G_4 Member Posts: 5
    ECU with hi SEER A/C unit?

    see response above.
  • Constantin
    Constantin Member Posts: 3,796

    Doesn't make sense, AFIAK, but then, I'm just a homeowner who happens to work in this field from time to time.

    I suppose it depends much on what you're after. If the goal is to make hot water cheap, then the ECU will continue to function since the gases coming out of a compressor will always be hot. In the south, the AC systems presumably run long and hard enough to allow water heating systems to take a lot of time off if supplementary heating via an ECU is enabled.

    That said, some of the benefit in years past was also associated with reducing the temperature of just-discharged refrigerant gases before they got into the exterior HX - thereby boosting HX efficiency on top of providing hot water. With high-SEER HX's, the temperature of refrigerants in the liquid lines can approach ambient so pre-cooling the hot gas discharge may not do anything for overall HX performance other than on the hottest of days, maybe.

    So, to be safe, I'd calculate out the benefit of the hot water production to the client and would consider any additional thermodynamic benefit a bonus. I would also clear the use of a ECU with the manufacturer of the equipment to be sure that you get some form of approval. For example, a potential problem could be too much liquid refrigerant accumulating in the HX because it's entering the HX already at a low temperature due to the desuperating coil.

    FWIW, I'm considering an ECU but have yet to contact Lennox regarding the possibility of using a desuperating coil with the XC21.
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