What is an unacceptable boil off rate?

[autonomist3k]

I just tested my new pot, with my new burner, the pot is 19.5" wide, and I kept the boil pretty low.

I started with 8 gallons, and ended with with 4.25 gallons.
is 3.75/hr acceptable?
That seems crazy compared to my keggles 1.25/hr.
Isn't that going to kill my efficiency?

 

[autonomist3k]

 

[Brettomomyces]

It won't kill your efficiency, but you've now got a beer that's a lot stronger than you planned for. That is a lot of boil off for one hour though, average is around 15% per hour, which would put you closer to what you were getting with the keggle. Could you go any lower on the boil next time?

 

[peterj]

3.75/hr is pretty insane! Seems like you should be able to turn your burner down to get less. Though judging from the cactus I see in the background of your picture, I'm guessing you're in a pretty dry area which will increase your boil off rate.

But a huge boil off rate is not necessarily a bad thing if you compensate with more water. You should actually be able to get better efficiency because you can use more water to sparge your mash and thus rinse more sugars off the grains. You may run into pH problems if you're fly sparging though. I would recommend batch sparging or BIAB.

EDIT: Just wanted to say that I have a pot and burner that's pretty similar to yours I think and I usually get around 1.25-1.5 gallons/hr.

 

[balrog]

What about making a 19.5" diameter disk with a 12" diameter hole in the middle, cutting down the evaporation rate during boil to a more reasonable 15%?

 

[autonomist3k]

To me it looked like a pretty low boil, but is it possible to boil too low?
I'm sure I can turn it down and still maintain a boil.

 

[autonomist3k]

What about making a 19.5" diameter disk with a 12" diameter hole in the middle, cutting down the evaporation rate during boil to a more reasonable 15%?

Would that cause any retention of dms?

 

[poptarts]

Dibs on kicking the next person that talks about boil off rate as a percent. That said, you should be able to maintain boil and have a lower boil off rate if you turn down your burner.

 

[autonomist3k]

I'll try turning it down as much as I can, and see what happens, I don't want to complicate it by mashing with more water or building stuff, I'll save that as a last resort.

 

[LandoLincoln]

My pot is also 19.5" wide. I have an electric rig. I get about a 2.25 gallons per hour boil off with it. Yeah, it looks like the water isn't boiling a lot, but it's doing the job and I don't have DMS issues. I'd recommend dialing the heat back a bit.

 

[singybrue]

How tall is the pot and what is the capacity? 10 gallons?
A short, wide pot will boil off more than a tall, skinny pot.

 

[cannman]

I had a boil off issue recently.

It turned out that I had two major leaks in my line, so even though the burner was on max, I was only getting a fraction of it's power, causing the time to reach boil to be excessive, therefore causing an insane loss (water evaporates even though you aren't at boil).

Tighten all connections! Take a bottle of soapy water or a bottle of StarSan and hit all connections to check for additional leaks. Check your hose too for needle pin holes that might cause a loss of fuel.

Once you hit boil, you might want to crack the fuel down a bit to maintain the boil, decrease boil-off, and save fuel.

Good Luck!

 

[autonomist3k]

The pot is 20 gallons, and 16.5" tall.

 

[autonomist3k]

I had a boil off issue recently.



It turned out that I had two major leaks in my line, so even though the burner was on max, I was only getting a fraction of it's power, causing the time to reach boil to be excessive, therefore causing an insane loss (water evaporates even though you aren't at boil).



Tighten all connections! Take a bottle of soapy water or a bottle of StarSan and hit all connections to check for additional leaks. Check your hose too for needle pin holes that might cause a loss of fuel.



Once you hit boil, you might want to crack the fuel down a bit to maintain the boil, decrease boil-off, and save fuel.



Good Luck!

I checked all my connections when I boiled, it only took me 12 minutes to get hot sink water to boil though, so no problems there.
Thanks

 

[balrog]

Dibs on kicking the next person that talks about boil off rate as a percent. That said, you should be able to maintain boil and have a lower boil off rate if you turn down your burner.

Okay. Duly noted. Moving on.

 

[singybrue]

There you go - your keggle is tall and skinny, and your new pot is short and wide. More surface area=higher boil off.
If it were me I'd run another boiling test to confirm.