DIY pool heating

[oscarposcar]

Does anyone heat their pool with a home-made solar system eg metres of black piping? Does it really work? Any tips?

Thanks

[spanish_lad]

yes it does. mate has his pool running thru 800m of 1 inch black piping on the metal roof of his barn and the temperature difference in and out is about 12 degrees (during summer)

[Don]

I made up a huge spiral of black piping and yes it worked to an extent but being in direct sunlight, the whole construction became brittle after 3 years or so and started cracking and leaking. Bearing in mind the huge volume of water in a typical pool you need a huge solar collector to make much difference. I have since found that a floating solar pool cover is overall more efficient than the black plastic tubing as the floating cover also limits evaporation which is the largest cooling effect in the pool. However, the first pool cover came from Barcelona and also became brittle after 3 years so now I invested in a cover sold by an Australian company who give an 8 year warranty. Time will tell if it lasts the 8 years.

[casita-bonita]

How much would you expect to pay for solar pool cover in Spain? trying to work out whether I should buy one over here and somehow find space in the car for it when we move over or if there's little price difference just get one in a pool shop around Velez Malaga. For our 28ft x 12ft pool I'm looking at around £150 for a decent quality cover although you can get it as low as 30p/sqm.

[olive]

If you use black piping for solar gain, did you put it in the return to pool feed or in the pipe to the filter from say the drain hole?

olive

[oscarposcar]

I was quoted 1000 euros today for a solar cover with roller bit... and then someone else told me theirs only lasted 2 years. Maybe I'll just have to be braver about swimming in cold water...

[casita-bonita]

Ouch. Maybe I should forget our personal possessions and fill the back of the car with pool covers

We already have the roller so that's a saving. I was more interested in one to minimise evaporation rather that add heat to the pool as we already have a solar heating system in place and to be honest in the summer we turn it off as the pool gets more like a bath than somewhere to cool down.

[Beachcomber]

If you have a solar cover you need to protect it from the sun with a special cover when it is rolled back on the roller otherwise there will be a terrific build up of heat towards the centre of the roller which will result in the destruction of the cover within a very short period of time.

I have never heated or covered my pool. In my opinion it is just not worth it for the sake of gaining an extra week or two at the beginning and end of the swimming season.

[julian]

having to protect solar covers from the sun doesn´t sound quite correct !! although you are right !!!

[spanish_lad]

like any plastic left out in the sun it will go brittle

[K chameleon]

Would the black piping work with corrugated metal sheeting covering it?

[spanish_lad]

yes, i think so.. but he has it on top of the corrugated, so its sat on the metal ?

[El Cid]

Would the black piping work with corrugated metal sheeting covering it?

No it wouldn't work. The use of black piping is because it gets very hot in the sun (because it's black) - if you cover it, it will probably not even get as hot as the covering.

Think about it, if you sat in the shade under a corrugated iron canopy would you get hot?

Sid

[Devils Advocate]

Interesting one. I think it would work as comparing sitting under a wriggly tin roof opposed to lying the steel directly on top of the pipes is not like for like.
IMO the pipes would still get hot via radiated heat and at the same time be protected from sun degradation.
Think about it when you make a heat shield for an engine or for other protective purposes you don't make it out of steel as it radiates.

Seem to remember a punishment from years gone by where they'd put some poor sod in a corrugated tin box in the desert..................I don't think they would have bothered with the hassle if just leaving the guy roped to a tree was as painfull.

DA

[Don]

Casita-bonita, for a pool around your size you should budget somewhere around 800 pounds if you want one which will last. As I said, my first was a cheapie at a couple of hundred or so and only lasted 3 years until it broke up. Check out http://www.deep-blue-pools.com/pool_covers.htm for some useful references.

Olive, to save adding another pump into the system I took a small bleed off the pump outlet before the filter and returned it to the pump inlet. Given the huge flow of water through the pump this effectively slightly reduced the flow through the filter but any heat gained in the black piping was of course eventually transferred to the main flow to the pool.

Beach, quite correct in that when the cover is rolled up and not floating on water it can overheat and destroy itself so mine came with a ready made white reflective cover which slips over the rolled up cover and protects it. I would, however add that for me it is not just the extra week or so of extra use but the water and chemical saving which is so attractive. My pool chemical levels last a lot longer than when the pool was uncovered.

Julian, it is only the rolled up cover which needs protection, not the cover when in use floating on the water.

Sid and DA, having just had solar hot water panels installed, the principle could work if you were to cover the black tubing with sheet metal and somehow ensure heat transfer to the tubing. Perhaps laying the tubes out in a sealed box structure with a metal surface facing the sun and flooding the whole box with water or another heat transfer fluid would protect the plastic from UV degradation but capture the heat. Notable for the rooftop solar panels every little plastic connection and pipe in the system was lagged with UV reflective tape to avoid UV degradation. However, we are getting away from a cheap and cheerful system now and more into a well designed and built (and accordingly more expensive) system. Constructing it all out of black copper pipes would work very well but would be even more expensive.

[casita-bonita]

Casita-bonita, for a pool around your size you should budget somewhere around 800 pounds if you want one which will last. As I said, my first was a cheapie at a couple of hundred or so and only lasted 3 years until it broke up. Check out http://www.deep-blue-pools.com/pool_covers.htm for some useful references.

That's still an ouch. I have seen 500 micron covers with 5 year guarantee for under £250 over here.

[El Cid]

Sid and DA, having just had solar hot water panels installed, the principle could work if you were to cover the black tubing with sheet metal and somehow ensure heat transfer to the tubing.

The advantage of using uncovered tubes is that they are black so they absorb far more heat than a steel panel. Perhaps painting the steel black might be the answer.

As for UV degradation of the plastic, it is a question of using the right materials. Good quality irrigation piping should last for more than 3 years. We have piping in direct sun that is as flexible as the day it was installed 6 years ago and it runs at up to 6 bar pressure with no problems.

Sid