OK then...
Well its just been tested!
Left the boiler to settle for 20 mins from boiling, hooked up my bits of copper pipe and garden hose and turned on the cold water.
At a sensible flow rate of wort it was able to cool to 55°C
At a slow trickle I can get it down to 34°C
I ended up with 13 Litres of wort @ 45°C in the FV (with lots of flow rate changes and temperature checks)
If I'd let it trickle it would have taken ages to empty the boiler so its currently sat in the bath cooling off some more.
Here's the pics:
It does prove that if you were to gang 3 or 4 of these up you could probably get a lower temperature and a faster flow, but that goes against my simplistic idea and I'm going to go buy a coil of 10mm copper pipe... 10,15,20 metres???
