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bblaze
17th May 2009, 10:51 AM
Would it work
Been think of getting 20m of 5/8 copper pipe and bending /\/\/\/\/\/\/\/\/\/, well some thing like that, fitting a relief valve and mounting on my roof to get the sun, roof is brown colorbond. My thoughts are to feed the high pressure cold water in one end and out the other into the electric hot water system (return pipe would need to be insulated). Surely by feeding hotter water into the electric hot water system it would not operated the element as often thus making it cheaper
Whats your thoughts
cheers
blaze

BigJon
17th May 2009, 11:58 AM
Sounds reasonable to me.

spudboy
17th May 2009, 12:52 PM
Good idea, as long as you are using the hot water during the day.

Xtreme
17th May 2009, 12:59 PM
A friend of mine had an outdoor hot tub - simply circulated the water through multiple coils of black poly pipe by natural convection, Didn't require any additional heating at all.

Roger

fraser130
17th May 2009, 01:57 PM
As said above, it would only help if you are using the water during sunny weather.
if your system is mains pressure, there may be a drop in the flow rate because of the extra pipe.
I hate to say it, but it would really only provide a few litres of hot water each time, then the pipes would cool, and the water going into the heater would be only slightly warmer than the supply.
you really need the water to be constantly circulating to keep taking the heat away as it flows through the system.


Fraser

bblaze
17th May 2009, 06:24 PM
what if I was to use 20 to 30 meter of 1" polly pipe (maybe a roll still coiled up), dont know how to work the volume of the pipe out but it must be a bit. I reckon a shower would only use 30- 40L of hot water
have to think some more but I think it may have some merit.
cheers
blaze

Xtreme
17th May 2009, 06:31 PM
what if I was to use 20 to 30 meter of 1" polly pipe (maybe a roll still coiled up), dont know how to work the volume of the pipe out but it must be a bit. I reckon a shower would only use 30- 40L of hot water
have to think some more but I think it may have some merit.
cheers
blaze

See post #4 this thread.

Roger

pop058
17th May 2009, 06:34 PM
30 mts of 1" poly would hold a bit under 15 lts. would be better if you could circulate a larger qty of water during the heat of the day and store that to feed your mains system. The idea has a few issues to be resolved, but a good concept.

Paul

Blknight.aus
17th May 2009, 07:12 PM
if you can get a clean one....

put an lpg tank horizontally on the roof.

set it up like a convection tank with your coil of copper or mains rated poly pipe.

Feed the cold water in at the bottom and the hot water out at the top of the tank.

Or just install a solar hot water system.

clean32
17th May 2009, 07:32 PM
a few years ago i chucked 30 meters of green garden hose on the roof, it worked well, even at night the water is not as cold as the water coming out of the ground

bblaze
17th May 2009, 08:44 PM
if you can get a clean one....

put an lpg tank horizontally on the roof.

set it up like a convection tank with your coil of copper or mains rated poly pipe.

Feed the cold water in at the bottom and the hot water out at the top of the tank.

Or just install a solar hot water system.

Half the fun is the thinking, debating the pro's and con's of such a thing and then if able to build it, doing it.
The thing I dont want to get away from is mains pressure (town supply with good pressure), So without some type of valving to stop the mains pressure backfeeding into a low pressure reticulation system I think I would blow something up.
cheers
blaze
ps
thanks for imput and ideas thus far
cheers
blaze

harlie
20th May 2009, 11:40 AM
My Dad has a Solahart and there is a mod that may interest you is, the HWS is a thermo siphon unit with the tank above the panels. He has put a tee on both the lines between the tank and the panels and run a ½ inch copper pipe around the chimney for the fireplace just under ceiling height.. This line thermo siphens just like the panels when the fire is going so on a cold and rainy day (like today) his solahart is boiling, and it’s so simple.

Casper
20th May 2009, 12:49 PM
Many years ago on a farm we lived on we had the hot water going through the combustion stove in winter and a gal pipe grid on the roof in summer.

It was switched over with a 3 way ball valve located at the side of the electric hot water/storage unit.

The water used to get so hot in both winter and summer that you could make a cup of coffee straight out of the tap.

I cant remember specifics as I was only a kid but I know it worked and we rarely ran the electric element.

My Dad used to switch it onto boost every now and then when the fire was warming up just to make sure it worked properly.

Pedro_The_Swift
21st May 2009, 05:23 PM
reported.

muddymech
21st May 2009, 05:26 PM
beat me to it