Water volumes

[jjkeegan86]

Brewing for the first time tonight on my new ebiab system, I've done biab before and typically just used a simple web calculator, but my new system is a 15 gallon kettle, has an element and a false bottom. The false bottom sits around 3 inches tall and leaves about 3 gallons underneath it, it's all recoverable, I just wanted to know if I need to adjust my water volumes to accommodate all that dead space.

 

[Smellyglove]

It depends on how you like to brew. But it's 1/5th of your total volume in the kettle. It depends on your desired mash thickness and how much water you'd want to use for the sparge. If you don't fill it to the brim it's more than 1/5th of your used volume, meaning your mash thickness will go up, with the effects that has.

If you're targeting a desired mash thickness, for example 3L/kg which is pretty normal you can use ( x kg grains * 3 ) + deadspace / grains in kg.

That will give you how much water to use if you want to have a mash thickness of 3L/kg.

 

[jjkeegan86]

Should've mentioned it's for a 5.5 gallon target into the fermenter

 

[Smellyglove]

Should've mentioned it's for a 5.5 gallon target into the fermenter

Doesn't matter, as you should know your total water volume. It depends on mash thickness and how much you want to leave back for sparge water.

 

[jjkeegan86]

Doesn't matter, as you should know your total water volume. It depends on mash thickness and how much you want to leave back for sparge water.

Alright, so for no sparge, a 1.25 liter per pound mash thickness and 16.75 pounds of grain, and 3 gallons of deadspace

(16.75 x 1.25) / (11.3 / 16.75) =31 liters or about 8.2 gallons?

 

[Smellyglove]

Alright, so for no sparge, a 1.25 liter per pound mash thickness and 16.75 pounds of grain, and 3 gallons of deadspace

(16.75 x 1.25) / (11.3 / 16.75) =31 liters or about 8.2 gallons?

For a no sparge you omit the deadspace. You just use all the water you need to since the deadspace is recoverable.

 

[Gravelscratcher]

This what has worked for me:
Fermenter volume + 1 gallon for boil off + .125 gallons/lb of grain.
(Assuming a 60 minute boil).

Depending on how vigorous the boil is, can dictate how much volume you end up with.

Edit: I'm using BIAB, not eBIAB, for what its worth..

 

[jjkeegan86]

This what has worked for me:
Fermenter volume + 1 gallon for boil off + .125 gallons/lb of grain.
(Assuming a 60 minute boil).

Depending on how vigorous the boil is, can dictate how much volume you end up with.

Edit: I'm using BIAB, not eBIAB, for what its worth..

Yeah that's about right for me? Do you squeeze your bag a lot to get to boil volume?

 

[Gravelscratcher]

Yea, I squeeze it. Probably dont have to, but I cant resist.

 

[HB2 HughBHomeBrew]

Yea, I squeeze it. Probably dont have to, but I cant resist.

Same.

I also agree that the dead space shouldn't affect your calculations since its all recoverable.