Crazy Geo-Thermal Idea

[atgreene]

I'm confused by the people saying that it will freeze the septic tank. I'm not saying to only install the loop in the tank but to use it to boost the temp of the loop by a few degrees. If the tank was at the end of the loop the temp of the water in the loop would already be around 55 degrees plenty above freezing. So how can that freeze the tank? I'm not sure how much it would boost the temp since I don't know how warm the tank gets in there I just know it melts the snow above it in the winter so its got to have some heat. The mulch isnt bad idea either but I wouldn't want to back fill the trenches with mulch since you would end up with ruts in your yard as the mulch decomposed. But if you excavated a large hole next the hose where the loop returns and coiled up some extra pipe and filled that with mulch maybe a some type of copper coil to help the heat transfer for a shorter coil but I'm not sure of the rules for joining the pex to the copper under ground or if that would be allowed

You hit the nail on the head. I've seen fields freeze, but not tanks in use. Why would you pull heat from the tank if it dropped below 60 degrees or so? Makes no sense, I would treat it as an urban legend until proven otherwise. Once it's insulated I don't see how it could freeze, or even get cold enough to come close to freezing. In 20 years of excavating, installing and repairing septics I've yet to see a tank freeze if it is working properly.