Dialing in boil-off rate: water vs wort

So I have discovered that I need to hone in my boil-off rate in BeerSmith. For all intents, is it good enough to test with water as opposed to wort, or will the boil off be significantly different between the two. I.e. I'd like to dial in using just water and not burn through a few batches of wort.

Thoughts?

No, it's not going to be significantly different.

Water will be a close enough first approximation. Then you can check how close with your 1st real batch. It shouldn't differ by enough to throw your numbers off too badly.

Check priceless' calculator as well. I believe that you can give it the dimensions of your kettle and it'll estimates your boil off rate.

why waste the time and gas?, since you never bothered to measure boil off before, brew yourself up a batch your normal way, measure it and next time you will know and can calculate.

I would say that when using water, you may be inclined or able to have a much more vigorous boil than with wort. I know that my heat goes down at the first sign of boil over, and will slowly increase from there. With water you don't need to do this. Of course if you use anti boil over product, than this doesn't matter.

Yeah my main issue and the reason for the post is that my hot break will currently cause a HUGE boil over if left unattended. I have a feeling it has to do with my boil off rate being too high and thus I am putting too much wort into the kettle due to what BeerSmith is calculating.

Hot break aside, if the actual boil off rate between water and wort isn't too far off, I'd rather boil some water and get it right rather than undershoot my OG again and end up with extra beer that won't fit in the fermenter. Thanks for the input!

FirstAidBrewing said:

Yeah my main issue and the reason for the post is that my hot break will currently cause a HUGE boil over if left unattended. I have a feeling it has to do with my boil off rate being too high and thus I am putting too much wort into the kettle due to what BeerSmith is calculating.

Click to expand...

I have your solution:
1) Don't leave your kettle unattended
2) Get a bigger pot
3) Put less water in your pot
4) Get yourself a refractometer and measure your OG as you boil
5) Use this link https://www.homebrewtalk.com/wiki/index.php/Beer_math

I don't think boil off has anything to do with hot break, boil off is only the amount of liquid evaporated from the boil, hot break is from the proteins doing their thing.

Haha
1. I don't, but it's a PITA to constantly watch it. I'd Ike to be able to walk away.
2. Would if I could
3. That's my main thought is that if I got the boil off rate correct, Beersmith would adjust and have me end up putting less wort in the boil kettle. I.e. more room to accommodate hot break.
4. It's more a matter of my boil off rate isn't right, so to get from say 7 gal to 5, it would be over a 60 minute boil which messes with the hop schedule.

And I mention the hot break because that is what boils over. Once I get past it, it's less of an issue aside from the occasional flare up. I understand it has no bearing on boil off.

my calculator will estimate your boil off rate based on kettle diameter. I've found it to be accurate as long as the boil vigor is somewhere near a rolling boil

For $5, get some ferm-cap...a couple drops before it boils and it greatly reduces your foaming. Also, I turn down the flame as soon as it reaches a boil. It does not need to be at full blast, just get the boil running then reduce until it is at a rolling boil.