Evaporation rate?

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hopmadness

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So my first all grain is done. Pictures below. What kind of evaporation rate do you guys usually have to deal with? I lost a lot more than I expected.

Also, my efficiency was way off...only like 55%. Pretty sad. I was a little on the hot side at mash in, my first temp. measurement was 159 F....so maybe that had something to do with it.
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I lost a lot more than I thought I would too- when I started using the keggle I made. I collect no less than 7 gal. now- given that I leave a good half in the keggle (Bazooka screens suck-IMO- and I don't want all that hop residue as well as other protein & left over Irish moss, etc) and that often leaves me with a light 5.5 gal in the carboy. I also cut out the Huge rolling boil I used to do).
Who crushed your grain? I've started to use Iodine to ensure that the mashing is getting along- but of course iodine will not tell you anything except that conversion is happening- not what percent is or is not fermentable, etc.
 
Congratulations on your first all-grain! Nice kettle!!

I get about 15%/hour with a pretty peppy boil. It depends a lot on your burner, your kettle, and how intense your boil is so you just need to experiment and see what you're getting and work with that. I boil outside, and I've found the ambient temp affects it too. I've done 25 all-grain batches, and I still don't hit my desired evaporation all the time.

55% is a start -- you're doing good! At least you have a potential cause (the 159 degrees). If you haven't read the sticky on efficiency I'd recommend it. I read it now and then.

Onward and upward!!
 
Congrats. i just finished my first all grain today also. I got about 15% an hour in boil off. I only hit 65% effiiciency.
 
Yeah I think the only way to measure your evap is to do a few boils and measure where you are at. I measured for my pot every 2.1 inches or so was a gallon on my pot, So I boiled 6.4 gallons(according to BS) and I ended up with almost exactly 6 gallons in the fermenter including all trub and hops. I was supposed to loose 1.41 gallons.
I lost about .75 gallons to evap/cooling, I put all my trub and hops in the fermenter and my evap set at 11% so thats why im still well above my 5 gallon mark. So my evaporation rate was just about 9% per hour assuming my cooling loss was 4% but it is probably a less since I started relatively cold and I am 6000 feet above sea level, it is probably around 1%. It was about 65 f outside at the time, and at night so the humidity was probably a bit elevated because we had some bad weather around.

I didn't have a huge boil because I could not tend to it all the time so it was closer to a simmer most of the time. My OG was way way over the top anyways so the extra water didn't hurt a bit.

Somewhere my math is wrong because when I set beer smith to my actual finish volume= 6 gallons and my actual boil off it says my boil should be 6.9 gallons and my boil off would be .69 gallons or so. Now im pissed off...
 
I've done about 5 AG so far and I've determined that I lose about a gallon per 1/2 hour..... so for Ed Wort's Oktoberfest I had 8.5 gallons of wort to get 5.5 gallons in the carboy (90 min boil). Hit the OG and volume dead on.... You just have to account for your own specific brewery. I came up short a couple of times and took a while to balance it out..... Keep very specific notes and you'll eventually get it down pat....
 
I've done about 5 AG so far and I've determined that I lose about a gallon per 1/2 hour..... so for Ed Wort's Oktoberfest I had 8.5 gallons of wort to get 5.5 gallons in the carboy (90 min boil). Hit the OG and volume dead on.... You just have to account for your own specific brewery. I came up short a couple of times and took a while to balance it out..... Keep very specific notes and you'll eventually get it down pat....

Yes....2 gallons an hour is about what I lost...but that seemed way high. It was actually less than that because I wasn't able to collect all of the wort due to all the hop "residue" at the bottom of the boil kettle....but still in that ball park.
 
It takes a few brews and then you will have a pretty good idea on how much you loose. I start with 8 gallons and end up with 5.5.
 
I learned this the hard way on AG batch #1, this second time I added an extra .5 gal, pre-boiled 7 total, ended up with 5.75 gal after the grains, and poured almost exactly 5 gal into the fermenter after the boil. Like other people said, you really need to just take good notes and make adjustments.
 
It takes a bit
2 galons per hour is a good number to start with.
You have a big variable in what you leave in the boil kettle. We dump almost everything into the fermenter which doesn't seem to cause any problem
Our rate of evap goes all over the place depending up on rate of the boil, out side temp, wind ( we boil outside) and how close we are watching things.
If you want to know where you are just cut the heat and let it stop boiling and take a measurement. Mark the inside of you brew kettle or put some markings on a spoon.

Remember that you have a lower volume when the wart cools down.

Get a lower volume up goes the alcohol %
Or dump in some water.
 
I lose 2.75 gallons in the hour boil, 13.75 gallons preboil, 11 gallons in the fermenters, using converted keggle:mug:
 
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