Using Radiant Alumipex for Solar Pool Heater

Hello everyone,
First time here, found lots of info but have question about using this type of piping. I've noticed most people use either black hose or irrigation pipe. I have extra black radiant heat hose and was thinking it would be much better. Its black hose shell with a thin aluminum shielding then thick white pipe inside. It says rated for 200F - 100psi and is 1/2 thick. Brand name caked Weil-Mclain Alumipex for Radiant 1/2nom 1216 PEX-AL-PEX.

Can someone please let me know if this would work. Thanks.


Picture of Using Radiant Alumipex for Solar Pool Heater
fst2011 (author) 17 days ago

hello DownUnder35M, thanks for taking time to reply. I appreciate all the info. Not sure if I'll be able to do the copper widow idea, stuff gets scrapped real quick up by me in NYC. I've seen allot of videos of people using irrigation tubing and then enclosing it to keep it hot and they seem to get really good results.

I think the tubing I have might be better then irrigation tubing but I'm not sure. The only reason I can think no one has tried it is cause it's expensive to buy vs. The other one. I've had this roll in my garage for longtime back when I installed the radiant heat in my house. Now that I've found a possible use for it, I thought better use it for this, then keep storing it garage. But maybe it's not as good that's why I figured I would ask.

Thanks again so much for taking out the time and hope someone might have some experience with this type tubing and share advice.


Damn, sometimes I have my lack of time :(
I did some pool heating for a friend of mine and of course the aim was to keep costs as low as possible.
From that experience I noticed not everthing that seems to make a lot of sense actually works for proper solar heating.
For me it comes down to this:
Only if the solution allows to heat the water with sufficient flow rate to warm up by at least 10° C it is worth trying and keeping.
Reason is simple: Even a small inflatable pool takes a lot of water and without proper insulation it looses the temp quickly over night.
So any solar pool heating system is useless IMHO if you need at least 3 days of full sun to heat the water by much more than what a simple black foil on the bottom would do....

Size does matter and by using simple irrigation pipe on the roof we had to literally cover the entire roof and use a quite slow running pump - was less than what a aquarium would provide.
Using the same in some sealed and glass covered enclosures worked much better (more heat trapped and UV turned into heat) but also caused problems with the piping when the water was not pumped through as they overheated and went really soft.
With similar stuff to yours this problem would be gone but the added insulation of the thick plastic will mean you struggle to use the sun good enough for any heating.
As transfer pipes they are great though.

Maybe you want to give our "final solution" a try, here is what we did:
A bunch of old window frames with windows from the scrapyard.
Some condensers from old fridges and freezers - the black piping on the back, which gets warm during use ;)
A lot piping and connectors to make it all fit together.
The condesors were cut to fit inside the window frames, where possible and required leftovers were added to fill empty spaces and all mounted on a black board to be screwed on the back of the window frame - forming a "greenhouse" with the condenser inside.
We used 3 condensers on top of each other, slightly moved sideways to gove an even spacing between the pipes.
All 3 windows of approx 1.2 x 1.8m.
The 3 layers of condeser piping were connected in parallel to allow a greater flow rate of the water.
The result was that each window heated the water in the pipes a bit more.
Enough that during autumn you could see the fog forming on the water once the sun was gone LOL
During the summer the heating had to be shut off several times as the wate temp in the pool went over 40°C and was a bit too warm for comfort.
Do not use condensers made from steel (magnet check!), only those made from aluminium of copper will do you good.
And for the aluminium ones you want to be carefull with the chlorine levels in your pool ;)