this post was submitted on 27 May 2026
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hmmm
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For things that are "hmmm".
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What I was thinking, was using an AC in my office and using the waste heat to heat up the water in my boiler
The HVAC technician I talked about that laughed at me and said, that's science fiction
But I don't really get why.
Wouldn't that be just a heat pump from the perspective of the boiler and an AC for my office?
Edit: to clarify, I'm aware, that I can't heat up the water to the level I want with that, but I could pre-heat it, so I don't need so much power to heat it the rest of the way
Edit 2: and I guess, there is my answer
My boiler usually doesn't get that low on heat, that this would really make an impact, as it usually hotter than the waste heat
Still, I think, there should be a way to gather the waste heat somehow
You'd need a custom rig to do that, the exact hardware probably doesn't exist. Maybe someone has instructions for a similar DIY project out there.
I'm not gonna dissuade you from tinkering because maybe you'll invent something cool. There might be a better way to reuse the heat from a freezer or a fridge or an A/C, even if it's not to boil your water heater.
Maybe it could keep your plants warm in the winter, or heat your toilet seat, or your aquarium, reptile habitat, or hamster tank. Maybe it could warm up some blankets, our some pouches of sand or pebbles that you can put under your blankets. Maybe warm an incubator or a humidor or a dehydrator. The world is your oyster.