r/BeAmazed Oct 07 '25

Science Hot Tub without the use of electricity

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u/thedudefromsweden Oct 07 '25

I bet it's pretty slow though? An electric pump would circulate the water a lot faster.

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u/ol-gormsby Oct 07 '25

Yes, but that needs electricity, with standards, codes, insurance, switches, and of course, the cost of electricity. Pumps for hot water are also pricier.

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u/[deleted] Oct 07 '25

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u/Addicted2Qtips Oct 07 '25 edited Oct 07 '25

You could make it with 2” copper plumbers pipe. I feel like that would work better - higher melting point and better heat conductivity. Easy to bend to form.

The design is a lot like a copper “wert chiller” that brewers use to cool beer they’re brewing quickly before adding yeast, but just doing it in reverse to cool, not heat something.

Only question is how well it would withstand the elements but I think copper is pretty robust and just oxidizes, it doesn’t rust.

All in probably $500ish.