Quoting: Cunning Plan
Although, isn't it the wrong time of year to be doing that?
Yes and No.
Yes, because you wouldn't be using a pool like this in Winter (this was only a experiment . . . . )
And
No, because you don't need to heat it much in Summer - only in Winter.
So.
How did it work - Baring in mind that the capacity of the pool was around 2,100-2,200 litres (over 2 tonnes of water !!!) ?
The Results :Reading - 1Time : 0hr 0mins
Ambient Temp = 17*C
Pool Temp = 13.5*C
Ex. Output Temp = 14*C
Reading - 2Time : 0hr 30mins
Ambient Temp = 17*C
Pool Temp = 15.5*C
Ex. Output Temp = 22.5*C
Reading - 3Time : 3hr 15mins
Ambient Temp = 16*C
Pool Temp = 24*C
Ex. Output Temp = 32*C
Reading - 4Time : 4hr 30mins
Ambient Temp = 15*C
Pool Temp = 27.5*C
Ex. Output Temp = 44*C (!!!)
At this point my rigged input hose was leaking pretty bad.
Sorting it would've meant stopping the test and faffing about for a bit and it was getting late (we were heading out to a party a bit later) and I didn't want to risk the solder-joints overheating and melting.
So I turned the burners off, letting the pump cool the exchanger down . . . . and then did what any man would.
Overall . . .
It went really, really well.
I said previously that this would be absolute worst case scenario and this was the case for so many reasons . . .
i) The BBQ was un-insulated so the amount of heat wasted was incredible. The next incarnation will have furnace type insulation.
ii) The lid didn't shut and there were holes ! - Obviously letting out more heat . . . The next incarnation will have a lid made to suit the exchanger.
iii) The burner positions were not ideal. They ran perpendicular to the manifolds and I reckon turning the burners through 90 degrees would help a lot.
iv) There was no gap between the flame and the pipes . . . This meant really poor air-flow resulting in a cold flame. The next version will have bars to lift the exchanger off a bit and vents in the top to control the air flow (hopefully to find the most efficient burn combo).
v) The water pump was pumping too fast. It was the only pump I had available but I knew right away it was simply not giving the water enough time to heat. I put a reducer on the outlet that probably helped but even then the average circuit heated the water by 7*C
vi) It was cold out ! - The original plan for this was so the pool could be heated in Summer just to raise the temp a few degrees to make it more comfortable for Jensen . . .
vii) The pool had no insulation or cover. Obvious, really.
viii) I had a gas leak. I didn't actually check the condition of the hose properly but after over three hours I noticed significant cracking in the gas pipe near the bottle. Nothing too major (not enough to pose a danger) but this is gas which should've been being burnt !!
