Low pre boil volume,gravity to high

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dave81

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Hello

So my issue since i built my 4v herms has been i never can reach my pre boil volume by a long shot but my gravity is way over what i want also.it seem like my mash is super efficient and doesnt really need rinsing so i end up having to dilute my pre boil wort with water to correct my volume and gravity.

Yesterday i did a brew
3.75kg bb ale malt
.25 wheat malt
1kg vienna
Est efficiency 70%
I sparged down to 1010/11 and ended up with 22l in my kettle (expecting 34) with a gravity of 1059 (expecting 1034) so i diluted with 12.5l of water.
I ended up not boiling as hard as normal and ended up with 27l (exptecing 25l) into my fermentor with an og of 1044 (as expected ).

My previous brew i did an experiment and set my efficiency to 60% wanting to make 45 litres(into fermentor ) of 5.8% beer and even after watering down 10l pre boil i ended up making 54l of 6.7% beer,but hooray i managed to sparge to my expected pre boil volume but it was way over expected gravity.
(Sorry cant remember my gravities for that brew but you get the message ).

Where could i be going wrong its really peeing me off?

Sorry for the extended spiel,cheers for the help.
 
What are your water volumes ( mash and sparge ) ?
Sounds like you haven't got them right. At a very rough guess you'd need 39L all up, if batch sparging just split it 50/50 to strart with.
 
Start using brew software.. When you get your equipment dialed in right brew days will run much more smoothly.
I started with Brewmate (free) and after a while changed to Beersmith (worth the money IMO.)
It all seems daunting to start, but as you adjust for volumes, losses and efficiency it gets much easier.

For your problems currently, I think you definitely need to work out your boil off rate (boil a set amount of water for an hour and measure what you are left with).

Do a brew with an hour boil..
Aim for a Pre-boil volume of (your final volume + your boil off amount) and don't worry too much about the gravity..
Boil for an hour, then measure what your gravity is... if it's higher or lower than target, adjust your efficiency down or up slightly for the next brew...
Also if you can get your boils consistent, your final volumes will be closer to the mark..

It might take a few brews to get right...
 
Sorry forgot that.fly sparge took about 45 minutes to get the 22l
I do 3l per kg of grain
15l in the mash and was supposed to be 24l fly sparge
*spelling
 
I use beersmith and have set up my profile.
6l boil off an hour usually ,2l to trub ,1l to shrinkage etc.
I have done many brews so have a fair idea of ny setup just cant work this issue out
 
So you used 39l of water and ended up with 22l in the kettle, using 5kg grain about 5l would remain in the grain which means you've lost 12l some where. That's assuming you measured the water out correctly, most accurate way is to weigh it ( 1l =1kg )
So you need to find the missing 12l
 
I didnt use all the water from the mash tun it was still full cause of the gravity of the runnings .i have sight glasses which i have set up by weighing water and marking lines on the glasses
 
The runnings coming out of the mash tun had dropped to a gravity of 1010 so i stopped sparging amd taking wort from the tun to avoid tannin extraction
 
I've got it , thanks. Channelling in sparge maybe ? Maybe try mashing/sparging equal amounts ( @ 4l/kg mash ) . Have you tried batch sparging , maybe worth a shot as it's simpler and if the numbers are correct then you can look to your fly sparging technique for later brews ?
 
I used to batch sparge with my old setup and have wondered about channeling with my keg mash tun/ with 10-12" false bottom but i am just getting stuck ob the fact my gravity is so high.i know the volume is low and all balances out when i add the straight water to the kettle
 
I suspect if you increase your mash to 4l/kg ( I find this makes recirculation easier anyway) and then sparge with the remaining 50 % of your water then your eff may go up to 75 (+/-), I'd batch sparge first to check this and then restsrt fly sparging if you really want to.
 
I would have to reread my book but how does the thin mash effect anything?
Cheers for your help
 
Personally I don't think it matters to the final beer , but does make recirc easier. I did start out all grain brewing with biab, typically @ 6l/kg, and the beer was fine.
 
I have no problem recirc i do a .9mm crush as it is.i may give that a try even a thicker masher as i thought less initial water may may allow me to sorge more
 

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