101 - thermometer calibration

Prior to Brew Day I like to calibrate my gear.

You don't want to tell the guy that can BIAB 20 pounds of dry grain, and get it soaking wet, out of the pot, without a block and tackle, that you might have been a wee bit off on the mash temp.

(lets see...20 pounds dry grain...I usually get about 2/3 qt water loss per pound...40/3rds....13 quarts...thats 3+ gallons, that's 25 pounds...plus the original 20 for the grain....hmmm...yeah...the guy that can hold 45 pounds of steaming grain at arms length, draining over a pot of 150 degree water....yeah....that's the guy we want to get the temp right for...)

And it's easy.

So this'll be one of a couple calibration posts....this time, analog thermometers.

Get a fairly large pot of water and bring it to a roiling boil.

Put your thermometer in...get it as deep as you can without actually touching the sides or bottom of the pot.  Check the temp.  As you can see, below, this one was reading about 215F.


Now look on the back of the thermometer...there'll be a little adjustment nut.  See it?






Put a wrench on it and turn it just a little.  Just a little means, really, a little...like 1/16th of a turn or less...maybe 1/32nd.

Put the thermometer back in the boiling water...same as before, deep, not touching the bottom or sides...wait a full 30 seconds...check the temp...

Repeat, as necessary, until the thermometer is dead on....like below...212F is what I read.





You can do this same adjustment with ice water and 32F...but it always seemed to me that 212 was closer to mash temperatures than 32...so I'll usually check the thing in some ice water, but not really pay much attention.

Anyway, that's it....after the water's boiling you've got 2-3 minutes, start to finish.

1 comment:

  1. You don't want to tell the guy that can BIAB 20 pounds of dry grain, and get it soaking wet, out of the pot, without a block and tackle, that you might have been a wee bit off on the mash temp. Fluke TI32

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