Did I just kill my new Tel-Tru?

njl

After my original BGE dome thermometer got all out of whack, I just recently had it replaced by a dealer with a Tel-Tru off a new display egg. 

I cooked a brisket today, and all through the cook, I had the egg held at about 250F, and the Tel-Tru and my ET732 were within a few degrees of each other.  When the brisket came off the egg, I removed the plate setter, opened up the top and bottom vents (to put it in self-cleaning mode) and went back inside to finish making the french fries. 

I kind of forgot about the egg, and half an hour later, when I remembered, I went out to shut it down and was puzzled to see the Tel-Tru reading 300F.  I carefully opened the lid and knew it was considerably hotter than that.  It looked perfect for doing a T-Rex sear.  Still wondering what was up with the Tel-Tru, I foolishly reinstalled my ET732 grate probe, and it displayed 492F for a second, then HHH, at which point I snatched it back out of there, singing some forearm hairs in the process, even with my pit mitts on.  While this was going on, and the lid was up, the Tel-Tru display came down to well below it's minimum normal readout, and I figured at best, I overheated it and it's going to need a recalibration.  I shut the vents, and then checked on it 20-30 minutes later, and it was reading 400F.

Is it possible it's still working just fine, and when it was showing 300F, it was really well beyond 700F and had wrapped around to 300F again (maybe around 1300F if the dial scale is constant the second time around)?  It's still cooling, and is down to 280F now.

ribmaster

What it did was go all the way around and back to 300. Then it lowered to 300. Mine has done it too. It should be fine.

njl

If that's what happened, it's the hottest I've ever seen the egg get.  I started this cook with the egg (a large) filled to the top of the fire box.  After cooking the brisket for 6 hours, the lump had burned a path from where I lit it (top center) down to the fire grate, leaving a big donut of unburned fuel.  This clean-out burned a large portion of the remaining fuel.

ribmaster

It does not mean that your grill got to 1400 or so. Bi-metal dial gauges are accurate within a limited range. Above 700 degrees another 2 or 3 hundred may have moved it back around to 300. It sound like what happened and it can get that hot wide open.

njl

Yeah...I kind of figured the graduations on the dial wouldn't be constant the second time around.  The dial is down to 50C now, which is the bottom of the scale.  The outside of the dome is still quite warm.

BOWHUNR

I bury + some the Tel-Tru on my mini on a regular basis.  I have checked the calibration just for kicks and so far it has had no ill effects.  It still reads 211* on the boil test for my location in Omaha which is nuts on.

Mike

Hillbilly-Hightech

well, that would've been a good time to use the Egg as a vessel to cast something from Aluminum :-\"

(BTW - I think the thermometer will be fine - when you get a chance, stick it in some boiling water & see what she reads)...

Mickey

Yep, been there and done that several times. Still works fine. They are tough.

SteveWPBFL

Now that the gauge has been determined to be fine, how clean did you get that grill?

njl

The grill surface is clean.  I just checked on it and used the wire brush to literally just knock some white ash off of it.  The TelTru may be hosed.  It settled right on 400C.  It's 70F here now.  I'm boiling some water now to check/recalibrate it.

njl

well, that would've been a good time to use the Egg as a vessel to cast something from Aluminum :-\"

(BTW - I think the thermometer will be fine - when you get a chance, stick it in some boiling water & see what she reads)...

I actually have a pair of garden shears that I'd like to heat up (again) and bend the handles, and was thinking I really should have held them over the egg for a bit.  I just did the boiling water test, and it was off (low) by around 100F.  Where's the normal resting place for a Tel-Tru at 70-80F?  Somewhere right around the C/F characters at the bottom of the scale?

Hillbilly-Hightech

Not sure about the Tel-Tru, but my stock BGE thermometer (before Tel-Tru) reads about 100 degrees all the time.  After I calibrated & adjusted it, that's what it needed to be at to be accurate at 212.

Hammond1

Which Tel Tru are you guys using. My BGE thermometer is running ~100* off now. 

Brownie

Which Tel Tru are you guys using. My BGE thermometer is running ~100* off now. 

The new BGE Thermometers are made by tel tru. You should be able to get it from your dealer.
Did you try to recalibrate it?

twlangan

I did pretty much the same thing on my 2nd cook (I'm an Egg newbie). Your reaction was exactly the same as mine - WTH?? Turns out that my Egg went nuclear on me very quickly and buried the needle back around to 200F. I had calibrated the Tel Tru when I assembled my Egg, but the resting point changed when the Egg cooled off completely after this unplanned mishap. I had to re-calibrate and found it to be off by about 50 deg. Since then, I have seen no ill effects and it is just fine. I would check and adjust calibration if I were you and use it. My guess is it will be fine.

FWIW, my cold Egg resting point is right about the same as Brownie's pic above. It varies slightly depending on outside temp.

njl

I did have to recalibrate my Tel-Tru after the post-brisket inferno, but it seems to be working properly again.