Stampede A little help

[SmokeyJoe]

Hi all,

I've got a 590 a little less than a month old and have a couple of issues I'm trying to figure out on. The first is the RTD probe calibration. I used 3 thermometers (the 2 meat thermometers and an old school oven thermometer) to measure the temp at the grate. The built in meat thermometers were an average of, 15ish degrees warmer and so I tried to use the offset to adjust based on the percent difference. I did that (adjusted 6% higher) and it only changed a few degrees. The original temp was 250 so it should have changed by 15 degrees, but it only went to 253. Tried it again at a different temp of 180 and same issue. What am I doing wrong here?

The second are the actual meat thermometers. I'm calibrating them using the ice bath method, but at higher temps port A deviates by as much as 5-10 degrees compared to port B and a control thermometer. Again, am I doing something wrong with the calibration?

Finally, I think I had some surface rust. I cleaned it off using barkeepers friend and what's below is what's left over. This is the left side of the barrel next to the hopper. Is this normal? It's used under a covered patio and I use a cover when not in use.

What does everyone think?

 

[Wslayer]

Lots of videos from RT to help people out. This may help you.

On the rust, I would contact RT.

 

[Fhughes]

Depending on what RT says about the rust, here is a product I’ve used many times to stop the spread of rust

 

[SmokeyJoe]

@Wslayer thanks for that! I’ve used that method each time, but the meat probes seem to deviate at temps >100 degrees. I’m wondering if the boiling water calibration might do better? As for the RTD, it’s strange that any adjustment under 10% doesn’t seem to change the temps at all. I’m still not sure what that’s about?

@Fhughes thanks man. I called with no answer and I’m waiting for a call back If they say it’s normal then I’ll try that stuff. It’s just weird because it’s on an area where no liquid gets to.

 

[mooncusser2k]

A few things to keep in mind (in no particular order):

The way you prepare an ice bath can mean a difference in the actual temperature being read. See this page for advice on the proper method. I'd also want to use a trusted other thermometer (my Thermapen) for comparison.

The meat probe calibration applies to a certain probe in a certain port - it's specific to that combination. You want to mark at least 1 probe so you know where it belongs once calibrated.

Calibrating the RT meat probes is done by degrees. That means if you calibrate at a low temp, there can be variation at higher temps (it's not a straight line).

Calibrating the pit temp is done by percentage. So it wouldn't be surprised by discrepancy between the pit temp reading and probe temps, even once calibrated. Using another trusted thermometer to compare might help.

As for the rust, I'd agree with reporting to RT and seeing how they respond. Good luck!

 

[Mastertech59]

@Wslayer thanks for that! I’ve used that method each time, but the meat probes seem to deviate at temps >100 degrees. I’m wondering if the boiling water calibration might do better? As for the RTD, it’s strange that any adjustment under 10% doesn’t seem to change the temps at all. I’m still not sure what that’s about?

@Fhughes thanks man. I called with no answer and I’m waiting for a call back If they say it’s normal then I’ll try that stuff. It’s just weird because it’s on an area where no liquid gets to.

I tried the 32 degree constant calibration and found the same results. I calibrated the meat probes to the temperatures I was looking for cooked meats using a trusted meat probe like the Thermapen Mk4 and this got the Rec Tec probes a lot closer to the true temperatures for what I was looking for a final cooking temperature.

 

[SmokeyJoe]

Update: They’re sending me a new RTD probe because I was also having issues with over/undershooting. As for the rust, he called it surface oxidation and said it can happen in humid states like SC. Ultimately their customer service came through and they said not to worry, that they’d make it right even if it means a new grill. Love Rec Tec.

@mooncusser2k Ill retry using the thermal energy method! I may not have let it sit long enough. I did tie a little zip tie around one probe to correspond to a specific port and each time I’ve gotten them to read 32F, but then they start to deviate as it cooks.

@Mastertech59 Im using a calibrated pen (not thermapen). you said you found the same results. Does that mean you had them deviate at higher temps?

 

[Mastertech59]

Update: They’re sending me a new RTD probe because I was also having issues with over/undershooting. As for the rust, he called it surface oxidation and said it can happen in humid states like SC. Ultimately their customer service came through and they said not to worry, that they’d make it right even if it means a new grill. Love Rec Tec.

@mooncusser2k Ill retry using the thermal energy method! I may not have let it sit long enough. I did tie a little zip tie around one probe to correspond to a specific port and each time I’ve gotten them to read 32F, but then they start to deviate as it cooks.

@Mastertech59 Im using a calibrated pen (not thermapen). you said you found the same results. Does that mean you had them deviate at higher temps?

Yes even when I calibrated the probes using the ice bath they were off by about 10 low so I just calibrated to a temperature around 180 using a thermapen MK4

 

[SmokeyJoe]

Cool, thanks for that. I’ll try your method instead.