I'm currently renovating our rural house in Bulgaria and just waiting for the weather to concrete the lid over our septic tank. I considering throwing a few loops of steel pipe down there before I do, ready for plumbing into a heat pump when I get round to that. Has anyone any experience with this? I'm hoping someone is already there before I climb down the rabbit hole of research. Snow doesn't settle on my neighbours septic pit! It seems to me that there is a lot of energy produced here that is never utilised.
Heat pump collecting heat from septic tank?
- Thread starter Dinglebat
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Steel, no. This is not a place to risk corrosion. It would be much safer to have a trench dug and extract the heat from the ground. However, if this is in the lowlands of Bulgaria, then a modern air-to-air heat pump should more than suffice and it would provide cooling in the summer as well.
You think? It's been incredibly mild this year but last year it say well below -10c for weeks and occasionally gets to -25. Air to air could still be viable?
This sounds like up in the mountains, -25C is -13F. I didn't realize it got that cold, but I was thinking more like temps in Varna or Plovdiv where it rarely drops much below -10C.
A good heat pump can still put out heat at -18C. Some of the newest generation units from Mitsubishi and Daikin claim colder operating temps.
A good heat pump can still put out heat at -18C. Some of the newest generation units from Mitsubishi and Daikin claim colder operating temps.
Mate, I had never considered that idea in my life and I'm really really into this stuff. I'm not going to use it in the way you suggested but it would be a brilliant way to take the chill out of the bathroom tiles! Thank you.
Fascinating! I'm new to heat pumps and the idea that heat can be taken from a minus temperature... 🤯
Thank you for your input.
The Chinese have also moved into this market. I think Midea may be the largest mfg of heat pumps in the world by now. Most of these units are mini-splits and not central hvac systems. I have seen them installed in Europe and Asia and now they are becoming popular in the US too.
You wouldn't want to overcool the septic tank. There are some very important bugs in there doing some very important work and there is a low temperature at which they will stop. I would expect most of this heat is from the decomposition and not from the temperature of the waste.
Very good point. You know yer chit.
maple1
Minister of Fire
Yes indeed.
Beyond that, you don't want any of it to freeze either. If things are buried very shallow, and there is no or not much snow cover - that could happen too. If we ever wanted to try to winterize our cottage, I think one of the first things we'd need to do is foam board over the septic tank. Haven't gone digging yet, but there is minimal dirt over it.
I’ve heard of people spreading straw over their tanks to keep them warm. Deep, for insulation. Luckily we don’t get that cold in my part of the country.
