How to Heat a Swimming Pool with an Air Conditioner | Ask This Old House
This Old HouseCited 3× on HN, 2019–2026
tutorial · general · evergreen · 2019–2026 on HN
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.
HN cites it as a practical demonstration of reusing AC waste heat, in threads about heat recovery.
Up next
15 mo on HNHeat Pumps: the Future of Home Heating
Technology Connections
17 HN recommender · 2021–2026
11 mo on HNJames Burke Connections, Ep. 1 "The Trigger Effect"
DRS_Education
12 HN recommender · 2019–2026
8 mo on HNWhy Heat Pumps are Immensely Important Right Now
Technology Connections
9 HN recommender · 2022–2023
7 mo on HNWhat Really Happened During the Texas Power Grid Outage?
Practical Engineering
6 HN recommender · 2021–2026
7 mo on HNIt’s Time To Break Up With Our Gas Stoves | Climate Town
Climate Town
10 HN recommender · 2021–2025
6 mo on HNGround Source / Geothermal Heat Pumps and Other Info
Technology Connections
6 HN recommender · 2021–2026
5 mo on HNHeat Pumps are Not Hard: Here's what it will take to start pumping
Technology Connections
5 HN recommender · 2022–2023
5 mo on HNConnecting Solar to the Grid is Harder Than You Think
Practical Engineering
4 HN recommender · 2024–2025
5 mo on HNWhy don't Americans use electric kettles?
Technology Connections
5 HN recommender · 2022–2025
5 mo on HNWhat Is A Black Start Of The Power Grid?
Practical Engineering
6 HN recommender · 2022–2025
4 mo on HNBest fan placement to move air through the house
Matthias random stuff
4 HN recommender · 2021–2025
4 mo on HNWorld's Largest Batteries - (Pumped Storage)
Practical Engineering
4 HN recommender · 2020–2024
3 comments from Hacker News
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. ▶ this video
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: ▶ this video Edit: chris_va has more details about why linking systems is hard: link
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. ▶ this video