Thermometers and their accuracy.

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Original poster
Dec 27, 2010
I got a new MES 40 for Christmas, the Sam's model.  The recommended breaking it in at the max. temp. 275 deg. for 3 hrs.  I did this, and while I was doing I thought I would check the accuracy of the temperature.  With the unit holding very nicely at 275 deg. I put my wife's oven themometer in on the to shelf it registered 250 deg.  Then I placed the probe of my Thermopen through the vent and it registered 315 deg.

I have checked my Thermopen in ice water and boiling water and it show to be accurate.  I wonder how accurate it is at checking air temp.  How do you know which is correct?
Yea I wouldn't go by the Thermopen for checking air temp. I believe those probes are meant to read accurately when stuck into meat. Mine usually reads pretty close to what the air temp is but still it isn't meant for that application. Do you have a digital thermometer you can stick into the smoker to monitor the temps? I don't have any experience with this smoker but there are plenty of folks who do on here and they can probably give you some suggestions. If it were be I would but two of my digital probes in the smoker then run it at what ever temp and see if my two digital probes were saying the same temp as the MES one. But if you don't have any other probes that kind of goes out the window.
I have a 30 inch mes it is the analog style but the with the temp Gage in the door was off 25 degrees.and me being a newbie it was really messing with my head.

Yea I would suggest 3 thermo-meters for the smoker and the meat. is reader supported and as an Amazon Associate, we may earn commissions from qualifying purchases.