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water heater setup question

mikeljon | Posted in General Questions on

What’s an optimal water heater setup, if you have normal demands some days and occasional high demand (many houseguests showering at once, or large spa tub being filled). I’ll have gas and electric. Has anyone had a heat pump electric for normal demand with a gas tankless for the high demand moments?

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  1. paul_wiedefeld | | #1

    That's certainly an option.

    Other options would include upsizing the tank, reducing flow at the shower head, increasing stored water temp, and/or increasing incoming water temperature by using a drain water heat recovery pipe.

  2. acrobaticnurse_Eli | | #2

    If/when I find the right heat pump water heater my goal would be the largest tank I could fit while maintaining room for maintenance, with it being set to economy/heat pump mode most of the time and the option to switch to hybrid mode when having many guests. You could even turn up the temp to 140 if you have a thermostatic mixing valve.

  3. inverti0 | | #3

    I would recommend two heat pump hot water in series: do a Rheem ProTerra Plug in (i.e., 120V) closest to cold water and a dedicated 240V Proterra closest to the fixtures. The 120V will be in heat pump only, and the 240V can be in energy savings.

    Here is a similar setup, albeit with one full electric and one heat pump:

    You'll have the efficiency of heat pump, benefit of redundancy, and the supply of an electric tank.

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