A simple solar thermal pool heater

Pool is 8,800 gallon 1-piece fiberglass with a concrete deck.

The main concept for the heater came from info on


View toward west end.  Pool is situated in south yard of our passive solar home, pictures of which can be seen at www.mildevco.net/house2

West end runs up hill, so it is slanted slightly to east and begins to get morning sun around 8AM.

System was installed 6-10-2012.  The 1" supply pipe runs around the outside of the gravel outside the fence, and act as the edging - the gravel sits on landscape cloth to prevent weeds. 

Local retailers only had clamps in two packs, which would make them VERY expensive.  Had to order them bulk to get a good price.  The water coming from the pipe when in full sun is quite warm, but I have to wait till I get the clamps on to fine tune the flow-rate.


I made a turntable / lazy susan out of a swiveling shop stool, a 4'x4' piece of plywood, and a 1' diameter disk of 3/4" mdf, centered on the plywood.  I hung a fishing snap-swivel on a rafter in the garage, and attached the free end of the 1/2" poly to it, allowing the supply line to spin, up and out of the way while winding the coil.

 We pre-inserted zip-ties under the coils as we were wrapping, every two coils near the center, increasing to every three, then every four out near the edges.

I had the 1" well poly left over from running a water line to my shop, about 150' of it, and the 3/16 wire rod was scrounged locally ( i.e. dumpster cut-off freebies from a local fabrication shop).

Without the cost of the 1", the installed cost of this system was around $170.  I got the 1/2" poly pipe, fittings, and valves from http://www.dripsupply.com/   If I had to purchase the 1", it would have been another $45 from them.

I used 1000' of the 1/2" divided equally into the four coils of approx. 4' diameter with a 1' hole at the center.



I used the same 1" pipe around the rest of the gravel areas, so the overall appearance is cohesive.

Close-up of the u-shaped stakes/pins.  I have a metal bender, but they could be made by bending the mild steel rod around a piece of galvanized water pipe.  They should get a nice rusty patina