Pit probe all over the place??

JBail

New member
I'm finding that I have to constantly adjust my pit probe offset which I know is a no-no.
I started off with cheap wal-mart probes. It would run fine for the first hour or so then it would "run away" even though the analog dial on my smoker still shows (250f which I set for).

Of course I blamed the cheap wal-mart probes. I purchased Thermoworks TX-1003X-AP pit probe and TX-1001X-OP cooking (meat) probe.
However, I am experiencing the same exact issues. At first I thought it might be a grounding issue with the probes. Drilled some holes, inserted a coupld silicone plugs... Nope. Kept them running in my office to see if they would vary... Not really. It's only when I am doing a live cook.

Any ideas?


The probe I have in my brisket seems okay and matches up with temps of my pen. The pit temp is everywhere that I have to constantly adjust.

- jeff
 

Steve_M

TVWBB Guru
Try setting the "A/C input line noise filter" option in the config to 60hz and see it that helps.
 

JBail

New member
Try setting the "A/C input line noise filter" option in the config to 60hz and see it that helps.
That was set to off, I set it to 60Hz. Didn't even see that. I'll do some more tests tomorrow. I'll see if it helps today. Thanks
 

Gary V

TVWBB Fan
another thing to check is your damper. Make sure the damper is not hunting or binding. If you built your own damper and purchased your servo, you could have got a chineese knockoff. Vorpal servos have a good history of working correctly and they claim they are made by Tower Pro. That`s the brand i have using and they are stable and work well. If you do not have the recommended capacitor installed on the servo power to common, install one. If you what to check for noise on probe, login into the configuration screen, then go back to home screen and press "N" on your keyboard.
 

JBail

New member
another thing to check is your damper. Make sure the damper is not hunting or binding.

Thank you, I wouldn't say it's what's causing my probe issue but I noticed that position of the damper (Using Adapt-A-Damper with Delta Fan and unknown servo) was off (almost 45 degrees) and wasn't fulling closing. It explains some of temp issues I was having. I was able to adjust for it in the config page. Thing is, I swore I've done it during the initial setup. If I keep noticing it dirfting away I'll replace the servo with better one.

I didn't add a cap to damper/blower. I'll do that before my next cook just to be on the safe side even though I am using a short cable. Also need to find a ELI5 PID tuning guide. But that's another subject.

I'll report back after my next cook. It will be a pork shoulder
 

JBail

New member
Finally got around to doing another cook. This time it was a pork shoulder.
Still having issues with the temps not being correct on the HM compared to my dial and handheld probes (both digital and analog).

It would start approx 25f off and throughout the 8hr cook it would slowly correct itself to reading closer to the correct temps. I did turn on the 60hz filtering option in the config and also added a 10uf cap to the servo.

When I am running this in my office, it seems fine. Later on I'll hit all the solder joints with my iron to make sure there isn't a cold joint. Other than possible RFI/EMI issues, I'm out of ideas.

 

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