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How to Heat a Swimming Pool with an Air Conditioner | Ask This Old House

How to Heat a Swimming Pool with an Air Conditioner | Ask This Old House

This Old House
0 HN recommenders · discussed 2019–2026
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About this video

A This Old House segment where Richard Trethewey installs a heat exchanger that uses waste heat from a central air conditioner to heat a swimming pool.

Why it appears in the archive

HN cites it as a practical demonstration of reusing AC waste heat, in threads about heat recovery.

AI-generated summary and labels from the source dataset; verify important details against the video. Source & credits.

From the Hacker News discussion

MichaelApproved · 2019-10 · reference

Houses with pools should use the waste heat from their air conditioning system to heat their pool. Unfortunately, the system requires an HVAV technician, an electrician, and a plumber to install. I’m also not sure how many HVAC techs are familiar with installing something like that. Seems like a great energy saver though. Here’sa video from This Old House on installing one of the systems. [VIDEO]

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energ8 · 2020-04 · reference

From my reading of heat pumps, mismatches in energy sources and sinks can make linking things together more complicated (aka more expensive) than is commonly available. For the pool <-> A/C case, This Old House did a segment on linking the systems: [VIDEO] Edit: chris_va has more details about why linking systems is hard: [LINK]

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alexpotato · 2026-07 · reference

This does exist btw. It's a stainless steel coil that you can put on your A/C and then run water from your pool over it to heat the pool. [VIDEO]

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