10g Megapot boil off rates

Does anyone else have info for the average boil off rate? I collected 7 gallons of wort yesterday and in a 75 min boil only ended up with 4 gallons in the fermentor. I know there was still a little with the trub, but it seems excessive. I also know that I could top up in the fermentor, but i didn’t want to lower the OG. Any thoughts? Do I need to start with 8 gallons?

thats a reaaly high boil off. Not sure how hard your boiling, elevation, humudity etc.
I have a megapot and at a two hour boil I don’t boil that much off

Wow, that sounds really high. I have a pot nearly identical to that one and I tended to see a bit over a gallon an hour (it depended on the weather a bit too, more like 1.5 gallons per hour during winter given the very low humidity air). I’m sure some would object but I’d put the lid about 50% on during the winter, I assumed that way DMS could still boil off but I’d lose less to boil off and wouldn’t need to use quite as much to heat it.

I’m pretty sure it comes down to the pot geometry, it is pretty wide which leaves a lot of surface area for boil off. I boil off less in my 20 gallon Blichmann, pretty sure that is because by comparison it is narrow and tall. The nice thing about the Megapot is that whirlpooling was quite effective for getting all the hops and trub separated.

I start with 25 gallons in my Megapot and end up with 22 after 75 minutes.

I get a gallon an hour boil off on mine. A gallon and a half to two gallons if I turn the burner up all the way, depending on the humidity.

It really depends on your burner level. I usually get about 2 gallons in an hour, but can control it to 1.5 to 2.5 with the flame. I usually plan on 2.5 boil off then check gravity with 20 minutes to go and either crank the heat or turn it down to help me reach SG.

I recently started thinking with the 2.5 extra gallons to start that my hop utilization has been high. My beers have been on the bitter side. I think I need to lower the bittering charge to compensate.

I average 1.5 gal/hr with my 10 gallon Megapot, using a fairly strong boil (though I wouldn’t say aggressive). I start with 7.5 gallons, boil down to ~6, which puts 5.5 into primary after straining, which puts 5 gallons in the bottling bucket.

I usually boil off between 1 and 1.15 gallons per hour in mine (during a 90 minute boil).

I have a few questions, I have been brewing 5 gal. extract batches for the last couple of years on my stove thankfully I moved into a house last summer with a 2 car garage. (you would be thinking the same I was thinking when I saw the size of it). Any way I am in the process of getting all my equiptment set up to start brewing AG in the Fall with 2 Kegs one for HLT and one for BK. Giving that a keg holds 15 gals. to which I hope to finish with 10 gal Batches. In this thread I’ve read where some Boil from 75min to 90 min. is this better than 60 min boils, and how much boil off should I expect, also does the Heat & humidity in the summer effect boil loss. 90+ last 3 weeks uggh! Thanks to all!!