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Using grey water to wet geothermal loops?

mikkelsen | Posted in General Questions on

I can’t find any info as to if this has been done or if it is a terrible idea. it seems like it would not be too hard to use graywater to wet geothermal loops to help them work more efficiently. I’m assuming this is a bad idea since I can’t find any info on it…thoughts?

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  1. wjrobinson | | #1

    Eric, dry soils would conduct heat better if wetted. The Geo designers have data sheets they follow to do with your quest. Green building Talk has Geo yap... maybe Dana here can point you

  2. user-659915 | | #2

    I've heard that groundsource loops were at one time sometimes co-installed with septic system leach fields, I don't believe that's permitted now. Most environmental health departments have very specific rules about waste water outflows. I'd check with your local jurisdiction first and foremost before entertaining any idea like this.

  3. mikkelsen | | #3

    Thanks AJ & James.
    -yeah, you don't want them to pull heat away from your leach field, that's why i was thinking gray-water would be fine, not black-water.

    an added benefit that i can see is that separating your graywater from your black water should make your septic system healthier since it wouldn't have soaps, detergents, bleach, etc slowing the sewage from breaking down...& this would help your leach field & lengthen the time between pumping your septic tank.

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