GW volumes

[Chrissyr63]

hi all

have the Graham Wheeler book and just want to check my understanding on volumes.
He lists ingredients for various volumes but are these into the FV?
I use the volumes suggested but get about 19-20lt rather than expected 23lt. I think I lose 1lt to the bottom of my mash tun and rest from bottom of boiler and hops. Max boil volume is about 23lt but I usually get an extra Lt added through the boil.
So should my grain be calculated to 20, 23 or 24lt? I am using 23 at the

Hope this makes sense and thanks in advance!

C

[Dave S]

hi all

have the Graham Wheeler book and just want to check my understanding on volumes.
He lists ingredients for various volumes but are these into the FV?
I use the volumes suggested but get about 19-20lt rather than expected 23lt. I think I lose 1lt to the bottom of my mash tun and rest from bottom of boiler and hops. Max boil volume is about 23lt but I usually get an extra Lt added through the boil.
So should my grain be calculated to 20, 23 or 24lt? I am using 23 at the

Hope this makes sense and thanks in advance!

C

The quoted volumes are FV volumes, so you you need to factor in Boiler losses due to dead space and evaporation and also mash tun losses. For a 23 l brew I need to start the boil with 30.5 litres and end the boil with 26l. This should give me 23l in the FV. These volumes will differ according to your own set up.

[Chrissyr63]

thank for the reply Dave.
That is when I get confused - if you lose 3 Lt in the boiler dead space and I lose 2 won't the OGs be different because you started with enough grain for 26lt and I start with slightly less for 25?

C

[PhilB]

Hi C

That is when I get confused - if you lose 3 Lt in the boiler dead space and I lose 2 won't the OGs be different because you started with enough grain for 26lt and I start with slightly less for 25?

... no it doesn't quite work like that ... you'll both start out making your calculations for 23 lts ... but then Dave's extra 1 lt lost will (assuming all other things are equal) show up as a lower efficiency than you achieve ... so for future recipes he'll assume a lower efficiency, which will end up meaning he'll use slightly more grain, but as far as you're both concerned you'll both be scaling your recipes for 23 lts.

Hope that helps ... the thing to do is start taking lots of measurements and revisiting recipes after you've brewed them and adjusting the "assumptions" made about losses to get the volume you get in your FV right, and then calculating/adjusting the efficiency you achieve to scale your recipes appropriately. Don't expect to get it "right" straight away keep measuring and adjusting to claibrate your recipes to your system

Cheers, PhilB

[Dave S]

Hi C

That is when I get confused - if you lose 3 Lt in the boiler dead space and I lose 2 won't the OGs be different because you started with enough grain for 26lt and I start with slightly less for 25?

... no it doesn't quite work like that ... you'll both start out making your calculations for 23 lts ... but then Dave's extra 1 lt lost will (assuming all other things are equal) show up as a lower efficiency than you achieve ... so for future recipes he'll assume a lower efficiency, which will end up meaning he'll use slightly more grain, but as far as you're both concerned you'll both be scaling your recipes for 23 lts.

Hope that helps ... the thing to do is start taking lots of measurements and revisiting recipes after you've brewed them and adjusting the "assumptions" made about losses to get the volume you get in your FV right, and then calculating/adjusting the efficiency you achieve to scale your recipes appropriately. Don't expect to get it "right" straight away keep measuring and adjusting to claibrate your recipes to your system

Cheers, PhilB

That sounds about right to me..

[OvenHiker]

First of all I agree wholeheartedly with the advice above from PhilB and Dave S.

I just thought you might also find it interesting/helpful to see what the author has to say on his volumes in his book:

[...] all the Wheeler recipes are based on not collecting more than the target brew-length in the boiler. One reason for this is that most people boil in Electims, Bruheats, and Burco boilers, and cannot safely collect much more than the target brew-length. Also, the commonly-held assertion that you should boil from a higher volume down to your target brew-length is, in my opinion, based on a fallacy regarding hop utilisation. You will still have the same amount of protein in the wort no matter what the volume is, so the same amount of hop bitterness will be absorbed by the protein, and thus hop utilisation is largely unaffected.

It is far simpler and requires far less calculation and less room for error if you stop sparging when either your gravity reaches your chosen bottom limit or when you have collected sufficient in your boiler - whichever comes first. With Burcos and the like your boiler will be full before reaching the bottom gravity limit. You then adjust to volume or gravity in the fermentor. If your volume or gravity does not meet expectations, then lower your efficiency figure [...]

[Chrissyr63]

thanks all - the efficiency was what I was not taking into account. I can now see how they all link up.

C