Excessive Boil Off

nickofosho · Feb 9, 2015

Anyone had any issues with wind that lead to excessive boil off? I brew outside, and yesterday was a breezy brew day. I usually experience a 1 - 1.5 gallons per hour boil off. Yesterday was 2.25 gallons in an hour! OG was 1.054. Any thoughts?

shanecb · Feb 9, 2015

I would have thought wind would have caused LESS boil off due to blowing the heat from the flame around.

acidrain · Feb 9, 2015

I've experienced it too... wind will definitely lead to excessive boil-off.
Another good reason to have a climate controlled room to brew in, but like you, I'm resigned to outdoor brewing.
At least our weather is mild.

LLBrewer · Feb 9, 2015

Wow I've never considered the effect of wind on boil off. Living in the desert SW, I'm damn glad I have a garage to brew in.

brewkinger · Feb 9, 2015

In addition to the wind blowing, there are other factors in the rate of evaporation.
Ambient air temp and pressure, humidity and even boil kettle dimensions can affect the boil off rate.

BobBailey · Feb 10, 2015

I live in the high desert and find that humidity is the biggest factor for boil off. My normal rate is about15 to 17%. If it's cloudy, rainy or snowing I sometimes see as little as 11 or 12%.

nickofosho · Feb 10, 2015

I'm in Los Angeles, so the humidity was around 90%. I'd assume high humidity = less boil off. It was probably a combination of things, but I might set up wind shield next time. Thanks for everyones help!!