I have been doing All grain for quite some time, but less frequent as I would like. The last batch and the batch I brewed today both hit the pre-boil gravity, but missing my original gravity at the end of brew by 5 or 6 points. Nothing mechanically has changed with my system. The only thing I can think of why I am missing my gravity is that my boil off rate has just a little. My volumes seem to be very close to what they should be. Any ideas on what is going on with not hitting the SG.
Yeah if you’re not adding anything to the kettle then a lower boil off rate is the only thing that comes to mind to explain a lower than expected post-boil gravity having hit your pre-boil.
If you use propane something could be decreasing your output (i.e. spiders in your lines). Also even under “normal” conditions, I see a fair bit of variation in my boil between humidity changes and the difference in pressure between a full tank and.an almost empty one. I tend to judge my target boil vigor visually rather than targeting a specific point on the dial. That at least helps with the propane variation, but not the humidity.
I assume you mean you are getting 5-6 points below your target OG?
Maybe all you need to do is adjust the recipes for the efficiency you actually get.
The wind was variable on brew day and at times it was pretty gusty. i tried to make adjustments on the dial as conditions changed to keep my boil at a nice rolling boil and not jumping out of the pot at me. I was using a full tank of freshly filled propane.
Adjusting my efficiency might be the fix for this one. Knowing my luck these last two brews were a fluke and then I will adjust and I will be on the high side.
Try shooting for the middle range between and see where it gets you.