Originally Posted by LiquidFlame
I haven't measured the boil off rate yet. Tried to yesterday, but found a major leak where my temperature probe is. Took it to the welder this morning.
If 17.3 gal is right, how do people do 10 gal batches with kegs for their HLT, MLT, and BK?
They are not leaving as much behind, so they don't need to start with as much.
Volume into the fermenter + losses to trub/chiller/boil-off = starting volume (leaving cooling loss out of it for simplicity).
In your setup, you claim to be loosing 3+ gallons to boil-off, and 2.5 gallons never make it out of the keggle and into the fermenter (due to trub/chiller loss). That is 5.5+ gallons of liquid that needs to be added to your starting volume to end up with 11 gallons in the fermenter.
The 3+ gallons of boil-off seems high, but maybe not excessive for a 90 minute boil, but the 2.5 gallons seems like a lot of wort is being left behind.
In my kettle, I leave less than a 1/2 gallon behind for a "normal" beer, and about 3/4 of a gallon for a beer with a lot of hops (all I use is pellets).