Thanks Gerry. We're using a Brewzilla and Brewfather app and following what it says blindly. Brewed the same recipe twice now and will compare once they're ready as we did first brew 2 weeks ago and last Saturday bottled the first brew and did the second mash so not actually tasted the final product yet. We got the recipe from a Homebrew book, but that just gave final batch size, grain mix and weights, hop additions and OG, FG, EBU etc so we've plugged it in to the Brewfather app to get the overall process. It was a Pale Ale so used the Americal Pale Ale profiles in the Brewfather App.
The grain crus was the same in both batches as we bought the grain together.
Trusted the Brewfather app regarding lost volume, water volumes and brewhouse efficiency so the same assumptions in both cases.
Appreciate we need to tune the equipment profile, but just trying to see what our consistency is like initially to get a feel for where we're at.
Missed the recipe OG, but got reasonable consistency from the first brew to the second for OG. But ended up with 2 litre discrepancy, but at two different parts in the process.
In the first batch we were 2 litres down in the fermentor so added 2 litres into the fermentor In the 2nd we were 2 litres down after the mash so added 2 litres to the sparge water (not sure where its best to add water to make up batch volume). Ended up with the same OG (well one point difference between the two), but missed the recipe OG (achieved 1.046 against target of 1.049). As far as we're concerned regarding the process we did the same thing, we certainly set out to do the same thing, but can't think why we missed volume at different points in the process. We did empty the Brewzilla into the fermentor via the tap and tilted the unit to minimise lost volume. We have really been focussing on hitting batch volume rather than gravities as we're greedy and want to get the most beer! One difference was ambient temp as we mashed in the garage with the garage door open and it was alot colder last weekend compared to 2 weekends ago, so might that have affected evaporation rates?
Thanks.