Every year I seem to have an enormous pile of branches/leaves/garden clippings that I end up burning.  It always pains me to see so much energy 'go up in smoke' so for a while I had been thinking about how to harness it.

Earlier this year my hot water cylinder sprang a leak that slowly got worse and as the leak was 'buried' somewhere under the foam insulation it was impossible to find so warrented a replacement tank.  The old one sat outside for quite a while and as it weighed rather a lot (being steel plate) I didn't fancy moving it very far.

One morning I woke with a flash of inspiration  -why not use it to heat the pool? All I knew was that it was an indirect heating cylinder - I thought it would have an internal coil but it just might be usable.

I removed the outer steel case, the top plate where the hot water came out (perfect as a chimney) and the foam insulation and cut the base off with an angle grinder.  To my pleasant suprise it was totally empty; the heating provided by a second skin containing the hot water.

Absolutely perfect! I plumbed it up to a central heating pump to circulate water from the pool through the tank, set it on some fire bricks.

Having 'set it alight' a few times it works a treat. The water almost boils between entering and leaving and I have a safe controllable way of burning my garden rubbish.

And yes it does make a difference to the pool. We were still swimming in water at 28 degrees in october so it was well worth it.

My other pool heating attempt is a gas water heater with 2 heat exchangers stacked together (successful but less ECO friendly) and the next attempt will be using an air conditioner (thanks Organic Gav) in reverse - anyone got a 15Kw heat exchanger that has a 50mm entry/exit? ..will keep you posted!

Nigel

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Thanks Nigel you read my post ,this is the stuff we want, its not all about being green ! its making the best use of what you have, with what if any money you have to do it' thats why it has taken me 12 years to do all the work on my semi here in Skipton North Yorks, but has also got me my donkey shed in Spain by not having to pay out to over priced builders and the rest.
Keep up the good work
Phil ;D

I have a worcester heat exchanger I think it is about 6 Kw similar to Item number: 220704348528 on ebay UK @ 153 quid

Yours for 50 euros New and Unused 679832221

Regards Stuart

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Problem might be that it would need to withstand around 15 bar of pressure on the hot water side to work safely with R22 refrigerant. I'm not sure it would.. also it looks like it is a flame to heat transfer rather than a liquid to liquid transfer.  Looks like I'll have to make one out of something...

Thanks anyway..

Nigel

Hi Nigel yes its flame heat to water transfer!!

A couple of years ago we rigged up a heat exchanger to our diesel generator to recover the wasted heat from the radiator. Works a treat on our hot tub.

Nigel,
If your tank is made from Steel plate, it may have been some sort of pressure vessel, possibly from something like the Titanic ?

It's certainly a weighty piece of kit. All water cylinders here are steel (usually enamelled internally) though as unlike the UK where the hot water cylinder is copper and fed by a header tank, the water here is pressurised so the tank needs to be able to sustain working pressures up to 4 bar. The old one is a steel tank that then has another 'jacket' of water around it to act as the heat exchanger. If you pressurise a standard UK copper cylinder you'll quickly find you have a very large copper ball instead!

Nigel