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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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.
Wonderful news! Is there concern that it can be more prone to "plugging" up or decreased efficiency by waste coatings over time?
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.
This is great news. Was worried that I'd have to install dedicated grey water stacks. Thanks so much!