BeerSmith 2 Mobile Equipment help

Hey guys, I think I may be having some issues in beersmith calculating my strike water temperature. A few of my beers have finished at 1.000 and I think this is why. I haven't really edited by equipment profile much at all. I use a 10 gallon orange igloo cooler with a bazooka tube, and a 10 gallon pot to boil.

For a 10.5# grain bill, it tells me to add 13.3 qts of water at 163.7 F to get a mash temperature of 152. Does this sound right?

Current setup
Mash tun volume: 10 gallons (i just put that in there knowing the cooler is 10 gal)
Mash tun mass: 4 #
Specific heat: 0.30 Cal/g-C
Lauter deadspace: 0.25 gal
Adj volume for deadspace: no

Any help is greatly appreciated. I noticed when I take my temp reading, there is always a difference on a few degrees. One spot will be 152 and the next will be 148, etc. My thermoworks thermometer is calibrated. Thanks guys!

 

Are you milling your own grains?

I noticed when I moved from buying precrushed grains to milling my own I needed to add a few degrees for loss.

With precrushed I usually shot for 9 degrees over and now I typically shoot for 12.

However, are you preheating your cooler? This definitely helps to stop heat loss.

I usually put my hot sparge water into the mash tun for 10-15 minutes before mashing in it. This allows the cooler to heat up a bit.

 

My LHBS crushes it for me.

I am SORT OF pre heating? I have only been letting it heat up for a couple minutes, 5 at most. Next batch I'l heat it up longer and see if that helps get a consistent temperature.

 

If you're finishing at 1.000 it's not the mash temp that's the problem. I often mash in the 146-148 range to produce crisp session ales (I add some oatmeal to thicken it up a bit). This usually puts me around 1.008 if I'm starting around 1.045. The lowest FG I hit was 1.006 with a Saison where I used a good bit of simple sugars and I mashed at 144-148 for 1.5 - 2 hours.

If the beer is attenuating 100% the you're using a *ton* of simple sugars (like 90% of your fermentables) or maybe you have an infection. I've heard that pediococcus can attenuate 100%. You didn't mention anything off in the beer though, so I'm guessing this is unlikely.

My advice is to re-measure everything

What was the starting gravity?
What did beersmith think you should be finishing at?

Get a thermometer and measure your mash temperature. That'll make you feel comfortable with how your mash is affecting fermentability.

Try measuring the gravity with a different hydrometer. Maybe something is off there.


Mash temp doesn't affect fermentability to the degree you're assuming (which sounds like ~10 points).