Evaporation?

[scrumpyjack]

Hi
I was wondering if someone could give me a ball park figure to allow for evaporation. I will be using a homemade plastic boiler which maintains a steady rolling boil. I did my first small batch ( 11 litres ) AG on the weekend using a stock pot on the cooker and ended up with just over 9 litres in the FV so I added water to get the OG back to where I wanted it, but her indoors moaned about the smell that seemed to linger for ages. :nono: So I've made this boiler to use in the garage.
Cheers

 

[RobWalker]

right now, i ended up with 17L on a 23L boil. that's because of the cold though. i would expect a little less in the warmer months. but try to measure it accurately the first time you brew! that way you'll have pretty accurate figures :thumb:

 

[PD]

can anyone good with figures ( I'm a little number blind ) tell me how to work out the percentage for boil off, so I can add it in to my softwear.
For example 26 litres of wort beginning of boil, 19 litres at end of boil what percentage loss is that ?
thanks.....

 

[Vossy1]

Assuming a 1 hour boil, 100/26x19=73.1% left so 26.9% lost.

 

[PD]

Bows..... thank you oh Great one.... :

 

[Good Ed]

Hi
I was wondering if someone could give me a ball park figure to allow for evaporation. I will be using a homemade plastic boiler which maintains a steady rolling boil. I did my first small batch ( 11 litres ) AG on the weekend using a stock pot on the cooker and ended up with just over 9 litres in the FV so I added water to get the OG back to where I wanted it, but her indoors moaned about the smell that seemed to linger for ages. :nono: So I've made this boiler to use in the garage.
Cheers

I have a standard 30L bucket with a 3kw Backer element at get an average 9% evaporation loss figure per hour

 

[pittsy]

i have a 33l pot and boil 30 l in an hour with around 50g hops and end up with 23l in fv so i have 7l loss including hops etc .

 

[Good Ed]

i have a 33l pot and boil 30 l in an hour with around 50g hops and end up with 23l in fv so i have 7l loss including hops etc .

Loss to hops from displacement and absorption = 1.6L per 100g hops, from Aleman :thumb:

 

[theboytony]

FWIW I usually aim for about 10-12% evaporation per hour but to get that I have to turn the power down on my boiler to approx 1.6kw

 

[PD]

do you then keep a rolling boil going ?

 

[theboytony]

Its not a really fierce boil but it does have the churning kind of action that keeps the hops rolling around, I usually boil for 90mins and I'm pretty sure I've read about some recipes that call for a gentle simmer but over an even longer period of time

 

[PD]

:thumb: