Can someone check Ive worked this out correctly please..

[bigdave]

I want to make sure Im calculating this correctly before I bugger up AG#1..
Losses during brewing with my set up will be as follows:

Mash
1.25ltr per kilo grain
500ml dead space

Boil
2ltr dead space
16% evaporation
3ltr hops & trub

So to collect 25ltrs into the FV I would need to allow 6ltrs for evaporation giving me a total of 36ltrs into the boiler (which is what beer engine says). to get that 36ltrs I will need to mash and sparge a total of (assuming a 5.5kg grain bill) 50ltrs?..

[Brotherton Lad]

Something wrong there. I'd expect to start with about 38 litres of treated water to end up with 25l. It's your boiler losses that look big.

I just brew by trail and error plus all the info on here, so I can't query your formulae and of course I'm not familiar with your set-up. As you saw the day you came over, we prepped 8 gallons and ended up with 5 gallons ( 4.7kg grain bill and 60g of hops for the Ramsbottom recipe on this site).

[adm]

I use 1l/kg for the grain loss, and 10% per hour for the boil loss.

You can also use 15ml per gramme for the hop loss for flower hops.

[kay-jay]

seems excessive to me but appears to be worked out correctly assuming your losses are as you state. can you not try and tweak your kit to a more efficient less loss kind of thing.
if your figures prove to be correct i would consider using a lesser volume of water and back liquoring after the boil to dilute to the required strength. heating up that volume of water takes a lot of energy and time!!

its all well and good calculating the theoretical losses of your equipment but until you take the plunge and do your first brew you won't know for sure. for example depending on the shape of your boiler your evap could be as little as 10 percent. loss to hops is gonna be recipe specific more hops=more loss.

my advice would be to do your first brew as a basic recipe with a non specific gravity. aim for anything between 4 and 5.5 percent. schedule a brewday ,remember to enjoy it , see what happens .....learning about your losses in this way and figuring out the efficiency of your system will prove invaluable. for future brews you will be able then to aim for and achieve specific brewlengths and gravity.
good luck mate.


KJ

[gnorwebthgimi]

Here is the calculation for my equipment/set up:

Collect 28 litres of wort
2 litres lost due to 60 minute boil
1 litre lost to hops
2 litres lost due to trub in the fermenter (including hot and cold break material)
23 litres of beer (five gallons)

So I need to run 28 litres off the mash.

I put 10 litres into mash (more or less if required) and this will yield about 4 litres of wort, so that means I need to run an additional 24 litres of sparge water through.
that's two batches of 12 litres because I batch sparge.

I would suggest you run the risk of not collecting enough beer than the risk of collecting a really low gravity wort or worse tannins off the grain. So follow something similar to above and keep it simple.

You will have more than issues to worry about and things will probably go awry here and there. Good luck

[Blackjack]

To get 25 lts into the FV,
Lose 1.5 lt. to hops etc (26.5 Lt)
Lose 4lts per hr boiling ie. 6lt total (32.5lt)
With a 5.5Kg grain bill lose approx 7 or 8 lts. (40 lts.)

Bingo! Start with 40lts.

IF....you were only making 5 gallons ( ie. 23 lts.) with 4 Kg grain bill and maybe less hops then about 35 or 36 lts would be the correct amount of initial liquor and "typical" for most people.

VARIABLES... how hard you boil, lid on or lid off. 60 mins or 90 mins etc.

You are obviously aiming for more than 5 gals of something fairly substantial, it would be a pain to end up with too much weaker than required wort going into the FV. or not even fitting in the usual FV!. SO...you can always add but not take away. so use a couple of litres less liquor to start with and if too much boils away and the OG is too high simply add a litre or two of water to the FV prior to adding the yeast.

Good luck

[gnorwebthgimi]

You should never brew with the lid on the boiler, allows DMS to leak back into the wort.

[bigdave]

So, going on adm's allowances for hops and grain:

Mash
1ltr per kilo grain
500ml dead space

Boil
2ltr dead space
16% evaporation
1.5ltr hops & trub

Before my first brew I think I need to double check the dead space in my boiler then stop thinking and just boil!.. this time next week, I'll be sat on the bench in the back garden watching the boiler/hlt warm up...

Thanks for all the advice.

[Brotherton Lad]

Good luck, the first one is always a stab in the dark. You'll still make beer and then you can tweak your amounts to fit your set-up.

[bigdave]

Just out of interest, how will hops, trub etc affect dead space in the boiler?
Surely if I allow 1.5 ltr losses to hops and trub that will displace 1.5ltrs of dead space in the bottom of the boiler?....

So, going on the advice from the forum (and my own crazy maths) I'm allowing:

Mash
1ltr per kilo grain
500ml dead space

Boil
500ml dead space
10% evaporation
1.5ltr hops & trub

So, collecting 25ltrs into the FV will entail 30ltrs into the boiler. Plus 6ltrs loss in the mashing process giving a grand total of 36ltrs?...

If this buggers up I can always top up after the boil cant I?!?

[adm]

Yes.