Boil Off

[Rogermort]

What sort of hourly boil off are members that use three-vessel systems getting? I did a water test in my 75L stockpot with 3kw element yesterday and it was surprisingly higher than I'd been expecting - 9.2 litres after an hour of rolling boil.

 

[thesteve]

75 litres - Jesus, how much beer are you brewing Roger?

 

[Rogermort]

Biggest batch I've brewed at home has been 46 litres into the fermenter which took me to the limit! Trouble is my wife and my daughter's boyfriend have both got a taste for one of my American pales so I have to brew 'double batches' of that (two Cornies and some bottles). When I set up, I had delusions of going 'semi pro' but I've seen the light now! :)

 

[DCBC]

Mine's a 3 vessel system with a 100L boil kettle and I haven't done more than a 40L into the fermenter (56L boil) batch yet.

With a 5.5KW element my boil-off is approx -
20% boil-off at 20L/28L boil (too high I know!)
15% boil-off at 30/41L
12% boil-off at 40/56L

But this is all complicated by the fact that I can choose the boil power in 10% increments, so this is "lowest possible setting for a good rolling boil" - typically 50-70%.

 

[Rogermort]

Unfortunately my element control is on or off!