3 ms·
Here in Canada recovering heat from the drain can be used as part of energy efficiency code requirements in new builds. They can recover quite a bit of heat, a
by theluketaylor 7y ago
Here in Canada recovering heat from the drain can be used as part of energy efficiency code requirements in new builds.
They can recover quite a bit of heat, around 50% depending in inlet and outlet temperatures. Pretty good for a fully passive technology that has no maintenance or moving parts.
It does require a lot of copper, so the parts are about $1000 but it's a really easy install.
- frosted-flakes 7y agoThose things are neat. I always wondered why they were wrapped around vertical pipes rather than horizontal, because intuitively it seems like horizontal would be better, but that's not the case. I looked it up and it's because falling water in a vertical pipe will cling to the pipe wall, while in a horizontal pipe it will just sit in the bottom. It's obvious in hindsight, but I've never thought about the physics of water in a vertical drain pipe.
- willvarfar 7y agoThis, and blockages...
- twic 7y agoI've seen a design which exploits this by having the waste pipe flare out enormously - imagine two squat cones joined at their circular faces. You get loads of surface area for heat exchange, with slower flow across it, and no chance of blockage.