Counter current heat exchanger. How long should it be?

[tommyk]

Hi there,

I am looking to make a counter current heat exchanger to cool the wort off after boiling, before it enters the FV. I want to make a counter flow cooler set up. So a 8mm copper internal pipe for the beer to flow through, with an external hose pipe for cold water to flow through.

Any thoughts on how long I should make it?

Cheers, Tom

[Garth]

alright Tommy,

mine was about 10m long then coiled round a demijohn sort of diameter.

works very well, takes maybe 45 mins to an hour to pass 60 litres through it.

[Wolfy]

I'm pretty sure I made mine 9m long (half an 18m coil of copper pipe), it cools the wort to within a degree or two of the tap water, so that length works well for me.

[tommyk]

Great. Thanks for your help.

I heard 10 m was a good length, just wanted to check.

Cheers, Tom