What happened?

[suffolk]

I put my recipe in to the brewers friend calculator as I have done the past 3 brews.
It said the OG would be 1.041, It actually turned out to be 1.048

The boil water did evaporate more than I expected
Could that be the cause of the higher OG ?

 

[jeffpn]

Less water (volume) than expected would mean a higher gravity than expected, yes.

 

[suffolk]

Ok thanks for that.
Should I keep topping it up with boiling water to keep the original volume in the kettle ?

It was a new bigger pot than I have used before and never thought of evaporation

 

[jeffpn]

You'll adjust. I've been known to add water post boil to make up for lost volume. Other times, I'll just leave it and have a stronger beer.

 

[suffolk]

I ended up putting more water in and it is furiously bubbling away.
Will wait and see how it turns out

 

[Nosybear]

It'll turn out fine. There are way too many variables in yield for a tele-diagnosis. Your extract may have been higher than expected. As you mention, boil-off can affect yield - it's a big problem for me: I brew outdoors and the winds here are notoriously variable and strong. Gravity too high is not a bad problem to have. You just add water. Gravity too low is a different issue so all my settings are set to overshoot gravity. As long as I have spare volume in my fermentor, I can just do the proportion calculation and add water.

 

[J A]

The calculator can only project what'll happen if all the numbers match up with your real-world results. As soon as you get better efficiency or miss your boil volume, it's a new calculation. Find out what part of the process yielded different results from the projections and you'll be able to adjust your inputs for the next recipe.
New pot always requires a boil-test to be sure what you're going to get. Also boiling with the lid off as opposed to partially on will give pretty different boil-off, not to mention the vigor of the boil.
You got beer...all good!

 

[suffolk]

Noseybear
I did add water and now it is blowing the lid off lol ( np I extracted someand it has settled down.

J A
I did wonder about the lid being partially on, I know you can/t leave it closed as
it has to boil away some nasty stuff
I think the thing that really affected things is the boil off rate.
OH well on to the next recipe lol

Thanks guys

 

[jeffpn]

I bet most brewers don't have a lid on at all during the boil. I don't think I've ever seen it done.

 

[Ozarks Mountain Brewery]

you can partially leave the lid on bringing it up to a boil but while boiling you should not let any condisation fall back into the pot, changes of off flavors occur