Temperature Test on the Silverbac

[jlazar]

Cooks on the Silverbac have been finishing quicker than cooks on my previous smokers. So, I ran a test by comparing the set temp on the Silverbac to the average temps after 1 hour as measured using my Fireboard and probes. I ran the Silverbac at each set temp for 1 hour before beginning the test so the smoker temp would be stabilized.
Found out that my Silverback was running hotter than the set temps. At 220, I was running about +20 degree higher than the set temp. At 250, I was running +45 - +50 degrees hotter than the set temp. No significant difference between the top and bottom shelves. No wonder I was finishing earlier than expected.
To fix, I adjusted the auger speed to slow down the pellet feed, and I adjusted the RTD (the probe inside that give the actual temp reading on the Silverbac display).
After adjusting the auger and RTD, at a set temp of 225, if I place the food on the left side of the smoker, I average within +5 degrees of the set temp. At 250, I am almost right on (top shelf) or +4 on the left side of the bottom shelf. Again, not a significant difference between top and bottom. But, I should place food on left side of smoker. The right side runs hotter due to the heat moving in that direction, increased heat due to more exposure to the deflector plate as it moves across, and the exit out the chimney.
These results are averages. As the pellets light and burn, temps go up and as they burn out, temps drop. So a test with an average temp of 249 might see a lowest temp of 239 and a highest temp of 259.
If you own a Silverbac, you might want to run a similar test to see what results you get and if any adjustments are needed.

Silverbac Temperature Test
Set Temp vs Silverbac Actual vs Probes
Set Temp	Top Center
220	239
	+19
	Left Bottom	Right Bottom
	237	241
	+17	+21
Set Temp	Top Center
250	300
	+50
	Left Bottom	Right Bottom
	294	296
	+44	+46
Auger Adjustment
Original	12
New	4	Minimum
RTD Adjustment
Original	0
New	15	Maximum
Adjustment Results	Average Temps 1 hour
Set Temp	Top Center
225	230
	+5
	Left Bottom	Right Bottom
	228	237
	+2	+12
Set Temp	Top Center
250	249
	-1
	Left Bottom	Right Bottom
	254	261
	+4	+11

[Sweaty Paul]

Nicely done.

[jlazar]

Thanks. I had a 640 which I sold due to a move. Wish I still had it. Best smoker I have ever had.

[Sweaty Paul]

jlazar I do love my 640. Pretty bulletproof and makes great food. It’s going on 10 years old too.

[ItsAllGoneToTheDogs]

ALL pellet grills run different at the grate than what the unit is set at. The big concern should be if it is consistent at the temps you typically cook at. When you first get a pellet grill, especially if it has a stainless lid and/or cooking chamber, you need to do a few cooks with some fatty stuff (pork butt, chicken thighs, bacon, whatever) BEFORE you trust it to do an expensive protein like brisket or any overnight cooks.

Then the only way you should test the set temp is by clipping a 3rd party probe DIRECTLY where the grills thermocouple is. Anywhere else will lead you to chasing temps and possibly making things worse.

After you've verified that the grills temp is accurate or at least close, then you can check grate temp vs set temp. I always suggest checking at 225, 250, 275 and whatever other common temps you use. Usually there's a hot zone around the edges, and then depending on the exhaust type (stack or vents) and where the firepot is you will find the grill is even and consistent, or uneven and consistent, or like many cheap grills uneven and inconsistent.

Once you know the thermocouple is accurate (if your grill allows you can adjust settings), then you test grate temps and you either trust your grill if it was close enough, or you adjust the set temp higher or lower for what you want the grate temp to be.

While I applaud your data logging, I don't see where you tested this temp. If it wasn't attached to the thermocouple you'll want to redo this or you'll possibly be using bad data come the prime heat of summer.

Don't forget ambient probes will also be affected by the proximity of cold food until it warms up

[jlazar]

A difference between the thermocouple reading of 250 and the Fireboard at 300 is too much of a difference, especially since these are averages. The changes have put me within 5 degrees and +/- swings of 10 degrees. I did check the thermocouple and even made sure it was clean.

[ItsAllGoneToTheDogs]

jlazar that's what I'm saying, with minor exceptions NO pellet grill will have the grate temp the same as set temp. The thermocouple is usually in the back corner or in the back center, though a few have it on one side of the grate. Regardless, other than the MAK which has a roaming thermocouple (which I don't even use) none of them are gonna be 100% accurate set temp to grate temp.

[ItsAllGoneToTheDogs]

While the changes you made seem to be working for you, the best way is to ensure the thermocouple is accurate first before testing grate temp vs set temp and making algo changes. I've seen many people do it the way you did and end up chasing temps and getting rid of their grill because they were getting frustrated.

[klflowers]

When i got my Chimp, I tested and the temps were off by ~20 degrees. I adjusted the auger speed and now it swings around the set temp by 20-30 degrees in pro mode. You should also have a PID mode that holds close to a constant temp. I ran it in PID mode after I adjusted the auger speed and it held pretty well. I usually use a probe next to the Chimp probe and still swings around my set point - I always run on pro mode because the swings generate more smoke.

As an aside, the Chimp comes up to temp pretty quickly. So following a tip someone posted here, i put my meat on when i turn it on. It smokes a lot when it starts, and i don't let that go to waste.

[jlazar]

Thanks. My brother just got a Chimp. My tests were run in PID mode. Outside temp 70. When the Silverbac starts, it pours out tons of dirty smoke. I wait a little for that to calm down. Usually start in Pro mode at 180-190 for the first hour, then up to 225-230. I switch to PID mode once I wrap. The Silverbac comes up to temp in 20 min but I wait an hour to make sure it is evenly heated/stabilized. It usually overshoots target on heating up and then pretty quickly comes back down to the set temp.

[ItsAllGoneToTheDogs]

a small swing is to be expected, without it smoke quality drops