I think my thermometer is stuck or broken?

[meegwell]

Hi all, first non-introductory post...

I have a Performer Platinum - about 2 or 3 years old - with the thermometer built into the lid.  I've noticed lately that my heat is not easily controlled with the vents.  Actually, almost uncontrollable.   Example:  I get it hot up to an initial 500.  Then I close off vents, all the way on the bottom and half way (then 3/4 or all the way) on top and the temp still says 500 after 5 minutes.  If I open the lid then re-close it, the temp jumps down from 500 to say 300....I believe this is from the physical "bang" because I can reproduce this by smacking the thermometer a bit.

Anyway, I think its clear that it is stuck or sticky.  Do I need to clear the probe or spring or something or does it need replacing?  I haven't taken a good look inside yet.

[addicted-to-smoke]

Hi meegwell.

If you look at the temp probe you'll notice it's solid; nothing to clear out. But since it will register on the high end of the scale (500) it's likely working fine. Keep in mind lid temp isn't cooking grate temp (which is really what you should care about). Most times it'll read higher than actual grate temp. A $4 oven thermometer from the grocery store's baking or cooking tools section, left right on the grate will let you know accurately enough.

[toolhead]

Never tried to fix a bimetal therm....not sure you can.

Try cleaning the stem....

Alosbuse a digital therm probe fir comparison

[1buckie]

Hmmmm.......not sure.......

If you open the lid at that high of heat, it will lose a lot just to the air so 500 to 300 is believable there.....

This:
"Then I close off vents, all the way on the bottom and half way (then 3/4 or all the way) on top and the temp still says 500 after 5 minutes."

still sort of makes sense as it takes a little while for a change to come into effect, plus in that way, you're containing the heat...........at that point also, you've heated up the metal real well & that has a goodly effect ......make a move & wait about 15 minutes & see what's up......

It could be the therm is on it's last leg, but try watching it over a longer time & see what happens & maybe grab one of these little oven ones for the grate to check against....should likely be 25~35 degrees lower than the lid, if you're not sitting it right over charcoal.....put it in a semi-neutral area & see what that says.....

[Hogsy]

Have you tried the boiling water test with the thermometer ?
I'm pretty sure you can recalibrate them by turning the nut on the back of them if it's out

[addicted-to-smoke]

... Then I close off vents, all the way on the bottom ...

Nope.

Couple things to keep in mind:

1) Temp swings happen more slowly than instantaneously. Closing the intake is how you shut down the oven. So, don't. Just reduce the air intake but don't choke it completely unless you don't want to cook.

2) WAIT

3) Check it. Adjust, Wait more.

4) You can adjust temp also with the lid vent but just like with a car, you don't want to "reduce power" buy closing up the exhaust. Bad combustion (literally!) and bad taste on the food from poorly-running charcoal with nowhere for smoke to escape. Just ... normally ... don't.

5) Charcoal placement.

A lid thermometer will register whatever's mostly below it. If charcoal is piled beneath it but empty where food is (for an indirect cook) the lid thermo will give a false reading of "too hot."

***************

-- I'd recommend getting a cheap oven thermometer, placed NOT right on top of the charcoal area and at least 1 inch away from food. Open the lid to check that every once in a while until you get a better sense of what's going on. Very simple, very intuitive!

-- Know that this is an outdoor oven capable of having 2, maybe 3 different heat zones depending on how you set it up. That will affect what a thermometer reads ...

-- Practice with a specific cookup you want to do, search or ask for that here and take note of the pictures posted and such. That will illustrate HOW it was done and hopefully, WHY.


Keep going, you'll get it! And when you do (and you WILL) then shazam!

[meegwell]

Thank you all very much.  I think my "5 minutes" was on the short side...I've waited longer.  More importantly, this is my third year with this grill and I have always had very good control of the heat adjusting vents....something happened recentl.  I closed everything down as an experiment to see if the thermometer moved as the coals igstinguished.  I will clean the probe and get a cheap oven thermometer.  I sent weber an email earlier and they suggested the thermometer may be toast.

Thanks again everyone. 

[1buckie]

It happens......personally, I like knowing what's happening right at Meat Level (<< Technical Term) & those little deck therms work fine to at least get a ballpark of what's up....

It's kept me on my toes also, having to trust that the kettle's doing what it's supposed to without lifting the lid much.....
At certain intervals, it's time to check in & either move things, add things, or check to finish up, so then I get to look & confirm the curiosity......in other words, it keeps me honest & improving on the actual cooking......

Are the coals extinguishing at about the same rate they always have, after you're done cooking?