Dome thermometer question

bicktrav

Last night, I accidentally left the egg running at near-nuclear temps for about 30 minutes or so with the dome thermometer in.  I know when you're running it that high you're supposed to remove the thermometer.  Did I mess up the calibration?  How do you check?

dlk7

I put a pot of water on the stove and check the temp with thermopen and the dome thermometer across multple temps.  If it is consistently off you can adjust the dome thrmometer with the nut on the back.

dlk7

If you don't have a thermopen, just check it at boiling.

lousubcap

Get water boiling in a pan.  Insert your dome thermo and see what it reads.  Should be around 210*F (depending on elevation (212 at sea level)  but generally close enough).  Note off-set if not there.  There is a nut on the back of the thermo that you can turn to remove the noted off-set.  Then check in boiling water again. 

saluki2007

It would be a good idea to pull it out and check the calibration.  To calibrate, place in boiling water and adjust your thermo to 212 ferinheight.  When you put it back in, leave the clip off.  No need for it.  Plus you can turn it so that the needle points at 12 o'clock for whatever temp you are shooting for.

NPHuskerFL

>Pull thermometer
>get a pot of water to a roaring boil
>place 2 kabobs over pot to straddle thermometer and read temp
>at sea level you should read 212℉ (or 100℃ like @DMW‌ has suggested in the past because it's easier to read on the Tel-Tru)
>if it's out of calibration simply use a wrench on the adjustment nut located on the back of the thermostat (note: if it's to far out of calibration ---more than 100° it may be time to replace it---.
FWIW Tel-Tru makes some of the best available. I have a room thermostat that dates back to the 50s and it's still dead accurate.
Hope this helps you out.

bicktrav

Cool.  Will calibrate tonight.  Thanks for the help everyone!

gabriegger

what @NPHuskerFL said. although I use a pair of tongs.  Stem should not touch the bottom of the pot during calibration test

Carolina Q

Do yourself a favor... DO NOT USE a good pot for boiling the water!! Or if you do, DO NOT FORGET to remove the pot and turn off the burner when done. No idea why I grabbed an expensive copper pan for calibrating. I'm lucky the stainless interior didn't delaminate!

Multiple grits of sandpaper (100 up to 2000) and an hour or more of wet sanding finally got this copper back to a  presentable appearance. The bottom was the worst, but the sides didn't look so good either and also needed work. Never again!

RRP

Here's a simpler test to decide if you even need to check the calibration...where is the needle now resting that your egg is cold? Same reference to what you have gotten accustomed to seeing with a cold egg or does it show some temperature? Most all cold ones are wrapped counterclockwise to below zero, but if the "spring" in your thermometer got wasted last night due to high heat then the cold needle will be pointing somewhere above zero. If it is severely damaged then there is a good chance re-calibration won't fix it anyway. BTW I have had mine near 1,100 and it was not damaged, but then that is a Tel-Tru rated up to 1,000 not the lower ones like BGE now uses.