Beersmith Boil-Off Rate 2.3 gal per hour?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

djonesax

Supporting Member
HBT Supporter
Joined
Jun 29, 2014
Messages
515
Reaction score
50
So I really over shot my water on this brew which is weird because I had the same weight in grain as my last few brews with the same amount of water.

My last brew was about 11 gallons after the boil
24lb Grain, 17.25 gal, 90 min boil

This brew was about 12 and left me with lower gravity which is fine since its still 1.056.

I noticed that beersnith has a boil off rate of 2.3 gal per hour which seems high and makes sense why I ended up with a gallon too much wort. But that doesn't explain why my last brew was ok.

The only real difference is that this time I incorporate a pump and recirculated the mash for the first time but would that cause less grain absorption? Maybe I had a faster rolling boil last time month? I did slow the boil down a bit this time but it was always boiling and would be surprised if it made a gallon difference.

David
 
I've found being semi new brewer and using beersmith since last year that it took a couple batches to get my correct boil off rate. For a normal gravity beer with my system I collect 7.5 gal to boil down to 5.75-6 gal to get my gravity then I'll lose another .25 gal to shrinkage from cooling leaving me with 5.5 into primary and taking pretty much everything which I don't think is a bad thing. I always end up bottling 5 gal if not a tad more after cold crashing compacts everything. Do a couple batches with different starting pre boil volumes and you should know by then how much you'll lose after a 60 min boil. For me I have to go up to 8.5 gal for a 90 min but that may b a touch much as I just did one for a high gravity beer and ended up a couple points low og but I took 6 gal into primary instead of 5.5. It just takes time that's all.
 
You can run a test boil in your kettle to determine your approximate boil off rate. As said it might take a few brews to refine the numbers but you have to TELL beersmith the rate. It will then calculate the water fairly accurately. The final boil off rate is affected by the temperature and humidity. I use the mash numbers but then do a 2 part batch sparge. The first gets me a little more than half of the rest needed for preboil, I then measure what I have collected and do a second sparge with just a little more than I need for the rest.
 
I had a similar issues - I brewed a few months apart and got a wildly different boil off. Turns out the intensity of my boil was the issue and have since gone for low intensity that is easy to replicate if I do a 5 or 10 gallon batch and now the last three batches have been spot on volume and gravity
 
You can run a test boil in your kettle to determine your approximate boil off rate. As said it might take a few brews to refine the numbers but you have to TELL beersmith the rate. It will then calculate the water fairly accurately. The final boil off rate is affected by the temperature and humidity. I use the mash numbers but then do a 2 part batch sparge. The first gets me a little more than half of the rest needed for preboil, I then measure what I have collected and do a second sparge with just a little more than I need for the rest.

I also do the same. I mash fairly thin at 1.5qt/lb for normal gravity beers and 1.33qt/lb or a touch higher depending on what my cooler can take then drain and I usually lose about 2.5 gal to grain absorption and dead space under my false bottom then I'll do a 3 gal then 2.5 gal sparge to get my pre boil volume and I also like to over sparge just to make sure I get my pre boil volume. So far my mash conversion is around 89-92% based on the grain bill. If I miss my og after its usually cuz I didn't boil off enough of the pre boil gravity was a touch low. Still experimenting.
 
You can run a test boil in your kettle to determine your approximate boil off rate. As said it might take a few brews to refine the numbers but you have to TELL beersmith the rate. It will then calculate the water fairly accurately. The final boil off rate is affected by the temperature and humidity. I use the mash numbers but then do a 2 part batch sparge. The first gets me a little more than half of the rest needed for preboil, I then measure what I have collected and do a second sparge with just a little more than I need for the rest.

I know BS needs to be told the correct rate, but I dont remember ever changing it and I have never been over this much before that I recall. My last few brews were close to spot on with the same settings. So I was trying to determine what would have been the difference between last brews and this brew. The temp last brew was hotter and more humid.

Next brew I am going to use a calibrated spoon and take better measurements so I can see exactly what I am boiling off. But from what I can tell I boiled off about 3.5 gal in 90 minutes with a strong boil and 2.5 gal in 105 minutes (I added 15 minutes before the 15 min hop addition since the gravity was low) minutes with a weaker boil.

The temp
 
I know BS needs to be told the correct rate, but I dont remember ever changing it and I have never been over this much before that I recall. My last few brews were close to spot on with the same settings. So I was trying to determine what would have been the difference between last brews and this brew. The temp last brew was hotter and more humid.



Next brew I am going to use a calibrated spoon and take better measurements so I can see exactly what I am boiling off. But from what I can tell I boiled off about 3.5 gal in 90 minutes with a strong boil and 2.5 gal in 105 minutes (I added 15 minutes before the 15 min hop addition since the gravity was low) minutes with a weaker boil.



The temp


What are your BK dimensions? I have s 15g Update International & I avg. 1.5 per hour w/ a good rolling boil. 3.5 g in 99 min seems pretty high.
I test my BK's by filling w/ hot water & then measure the boil off for 60, 75, & 90 minutes. I use the avg per hour in BS equipment profile.
 
I know BS needs to be told the correct rate, but I dont remember ever changing it and I have never been over this much before that I recall. My last few brews were close to spot on with the same settings. So I was trying to determine what would have been the difference between last brews and this brew. The temp last brew was hotter and more humid.

Next brew I am going to use a calibrated spoon and take better measurements so I can see exactly what I am boiling off. But from what I can tell I boiled off about 3.5 gal in 90 minutes with a strong boil and 2.5 gal in 105 minutes (I added 15 minutes before the 15 min hop addition since the gravity was low) minutes with a weaker boil.

The temp

That's a huge boil off for 90 min. In my 10 gal aluminum pot I'll boil off 1.5 gal in 60 min with a nice slow bubbling/ rolling boil. You prob boil way to vigorous it shouldn't be jumping out of the pot but just nice rolling boil. Try it with just plain water to get the right feel for how hard to boil. And how did u boil off less with a longer time? That seems to me your boil is not consistent so you need to find the sweet spot with your burner.
 
And how did u boil off less with a longer time? That seems to me your boil is not consistent so you need to find the sweet spot with your burner.

That's what is puzzling. I was wondering if maybe since I recirculated the mash I has less grain absorption due to a more compact grain bed causing less wort in the kettle. I did boil more softly but that's a big difference. I'm going to calibrate a spoon and take more measurements next time.
 
That's what is puzzling. I was wondering if maybe since I recirculated the mash I has less grain absorption due to a more compact grain bed causing less wort in the kettle. I did boil more softly but that's a big difference. I'm going to calibrate a spoon and take more measurements next time.

That's prob your best bet. If anything I'd expect those boil off numbers reversed so something isn't right. It just takes time to figure out ones system. I'm just over a year into it and I'm still tweaking things.
 

Latest posts

Back
Top