Not hitting temps - please help

Hello all:

I've been using BeerSmith 2 for my AG brewing.  I've noticed that I am frequently low on the temperatures after adding water at the temps and amounts specified by the software.  For example, my mash-in this morning fell 3 degrees short.  Mash-out temps also tend to fall short.  I keep having to add more, hotter water to hit my target temps.

I've checked temps with 2 different thermometers that I know to read relatively true.  They agree on my temps.

I'm a slightly modified equipment profile, but have left all the defaults for 10 gal round igloo coolers that I use as mash and lauter tuns.  I have checked the box to adjust to equipment and grain temps and enter my ambient temperature in the brewhouse/garage. 

Am I missing something?  Any suggestions on what to adjust?

Variations of grain and equipment temperatures from what the software assumes, are often culprits.

My initial thought is that your equipment temperature may be lower than the software assumes. This will impact the specific heat calculation of the mashtun. From your notes, adjust the specific heat until the strike water temp goes up 3 degrees. Of course, to see the temperature change, you have to reassign the equipment to the recipe as you make the adjustment. You'll need to do this, even if you preheat the mashtun.

I get a seasonal variation of my equipment temperature. I just know to add a couple of degrees to the strike water temp in winter.

I found this suggestion somewhere else on the forum.
Start with your water temp 10 degrees higher than you need.
Wait for the water to cool down (maybe leaving the top open) to the temp you need.
Then add the grain. (I understand that BS will adjust for the temp of the grain)
This takes much of the variability out of the issue.
It doesn't matter if the air temp is high or low or the cooler was left overnight in the heated kitchen vs the cold garage, etc.

CharlesinAtl said:

I found this suggestion somewhere else on the forum.
Start with your water temp 10 degrees higher than you need.
Wait for the water to cool down (maybe leaving the top open) to the temp you need.
Then add the grain. (I understand that BS will adjust for the temp of the grain)
This takes much of the variability out of the issue.
It doesn't matter if the air temp is high or low or the cooler was left overnight in the heated kitchen vs the cold garage, etc.

Click to expand...

+1 to that.  Plus it's far easier to mix grains into water than get water into a vessel full of dry grain. 

Have some boiling water and ice cubes standing by until you dial in and learn your system. 

I recently starting paying more attention to the ambient temp settings, and my water volume, and nailed 150F last weekend.  Just takes time.

It is much easier to take heat away than to add it.  When you add boiling water to bring up the temp, the difference is around 50 degrees (or less depending on elevation). When you add cold tap water to lower the temp, the difference is around 100 degrees. That means it takes twice as much (or more) boiling water to heat it a given amount than cold water to cool it the same amount. For that reason my strike water is always a few degrees hotter than the recipe says, since it is much easier to lower than to raise the temp.

For how I brew and for the use of BS, this is a perfect example of you having to tell BS how you brew, not the other way around.

Don't get me wrong, I love the software but your empirical knowledge will far outweigh the info coming from the software. If you've followed the directions to the T and you're still missing the mark, stop doing what the software is recommending. Brew a batch with your own adjusted temps and see where you end up. When it's right then dial THAT figure in to your own brewing procedure.

My BS tells me to add water at a temp of 163.7º in order to hit a mash temp of 152º. Nope! In my system the way it's set up my strike water temp is around 170º to get my mash to about 150º. This is something that I know from brewing many times on that set up. There's no point in me having BS tell me new strike temps etc., when it's so easy to figure it out on my own.