Bull Another Temp Question: Strange discovery

[jaspry]

I've had the Bull since summer 2020 and love it. No complaints at all. I did notice something today though. Put on a smallish brisket last night around midnight (12+ pounds pre-trimmed). Cooked it overnight at 200 degrees. While looking at graph on ThermoWorks Signals, shows lots of up-n-down (see pic below) but all right around the 200 mark. All good.

Then, around 7:30 AM, I upped the Bull to 225. This is where it gets a little strange. When set at 200, it is right there at the 200 mark. When I set it at 225, it is still all up-n-down but now the average is around 250. Just thought it strange it would be in line with Bull set-temp at 200 and much hotter with Bull set-temp at 225.

I'm not writing about temps being hotter than Bull says. I've read plenty on pellet-feed, etc. Just thought it strange to be accurate at 200 but not at 225. Guess I should do set-temp at 250 and 275 and 300 and see what Thermoworks says on those settings.

Thanks for listening!

 

[chadinsc]

if you try it again maybe try it with your temp probe farther away from the edge of the grill. all the hot air comes around the edges of your drip pan and i know when i make sausage the links closest to the edges can burn even at 200. i bet you will get a cooler and more stable reading farther from the edge. if you do this let us know that result also. i love looking at data!

 

[Wslayer]

Just a shot in the dark, was the bull out in the sun when temp was upped ??? My 590 sometimes does some funky things when out in direct sun.

 

[kennethk]

interesting

 

[Waterboy]

I agree with @chadinsc, that probe is awfully close to the back edge of the drip pan. The heat is rolling up along the front and back of the grill and will be hotter on those edges. Try a biscuit test and place a couple of biscuits along the edge. It will really show where the heat is.