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Drain Water Heat Recovery Stack selection (Toilet?)

guillow | Posted in General Questions on

Hi, did a search and found nothing. Perhaps because it is so obvious. When retrofitting to an old house. Does one install a DWHR to the stack, even if it has a toilet draining to that stack?

Another way of asking the question: Does one need to separate solid waste stack from grey water stacks?

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  1. ThermoDrain | | #1

    Good day Guillow, you can install a drain water heat recovery on the main drain stack with toilet water flowing through it. The design is such that it has a double wall and therefore can never cross contaminate potable water. Hope that answers your questions!
    I attached the different ways it can be installed.

    1. guillow | | #2

      Wonderful news! Is there concern that it can be more prone to "plugging" up or decreased efficiency by waste coatings over time?

      1. charlie_sullivan | | #3

        Certainly no concern about it plugging up. It's a wide-open vertical 3 inch pipe. I've never heard of concerns about surfaces coating, and mine is working just fine after being installed for more than 5 years, with all the drains going through it. But I can't say I've measured to see if there's any change in efficiency.

        1. guillow | | #4

          This is great news. Was worried that I'd have to install dedicated grey water stacks. Thanks so much!

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