Navitron Renewable Energy and Sustainability Forum

General Renewable Topics => Inventions, Ideas, Innovation, Bodges etc => Topic started by: BARRAQUILLO on January 30, 2018, 10:47:38 AM



Title: Temp controlled water circulation pump.
Post by: BARRAQUILLO on January 30, 2018, 10:47:38 AM
hi,
i am in southern Spain. Despite the hot temperature, even during the height of summer the swimming pool water could benefit from a temperature boost. My idea is quite simple. i will run a length of 25mm black water pipe from the pool to the roof where a long coil of pipe will allow the sun to heat the water inside and return it directly  to the pool. The sun is very  hot and the water that is being sucked out of the pool will get to almost scalding very quickly. my problem is : A/ finding a pump that will be capable of sucking water from the pool to the roof[flat roof]. the head is approx 3mtrs with a total run from pool to coil of 8 mtrs. the return is the same in reverse. i assume that i  should be able to benefit from some siphon effect in the return.
                                   B/ find a way of controlling the switch on and off of the pump as the water is heated. a thermostatic control is preferable to a timer switch. if a probe is used how and where should it be installed.
thanks in advance for any suggestions


Title: Re: Temp controlled water circulation pump.
Post by: eabadger on January 30, 2018, 11:01:37 AM
my mate near estepona does something similar but done by thermo syphone so no pump needed.

steve


Title: Re: Temp controlled water circulation pump.
Post by: BARRAQUILLO on January 30, 2018, 12:35:02 PM
so how does that work. what is the set-up


Title: Re: Temp controlled water circulation pump.
Post by: biff on January 30, 2018, 04:45:38 PM
  You could use a solar powered 12volt pump but the pipeline would have to be totally air bubble free.
               If somehow the swimming pool was 10 mtrs above the roof or the black piping,,then the cold water would run down into the pipeline and the warm water would rise up it,,heating the pool in the process but with the warm water above the pool,,any movement to circulate would be slow,, very slow..I recon you will need a pump.
   You could link a digital thermo switch at the highest point in the pipeline and connect it to the pump. The pump needs to be well down the line or it might fry if run dry.
                                               Biff.


Title: Re: Temp controlled water circulation pump.
Post by: Westie on January 30, 2018, 06:05:51 PM
You probably already have a pump, just tee off the filtration pump output and feed the heating loop from there.




Title: Re: Temp controlled water circulation pump.
Post by: rogeriko on January 30, 2018, 09:38:13 PM
I tried that on my roof in greece, it dosnt work. Black pipe filled with stationary water does indeed get hot but as soon as there is a flow the heat output is negligable, I even covered my black pipe with perspex an a coil about 4 meters across took all day just to heat 200 litres. You need to find some flat panel solar heaters made from metal with a glass front. If you had about 6 large panels mounted below the pool or at least with tops of the panels level with the pool then they would thermosyphon. Flat solar panels can give you about 1kw of heat. (In the sahara desert the suns energy is about 1kw per square meter.) You need at least 20 or 30kw of heat to warm up a pool noticably. You would do much much better by covering your pool with an insulating bubble type floating cover and ONLY opening it when you want to use it. This stops your water evaporating which is the main heat loss. Of course if you want to look at your nice litup pool at night then it will be cold. I used to work with pools in Greece and now install heating systems for pools in the UK.


A good idea that didnt work.