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Author Topic: Temperature Difference RTD Probe & Dome Thermometer  (Read 3787 times)

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FredSG

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Temperature Difference RTD Probe & Dome Thermometer
« on: October 22, 2017, 01:55:18 PM »

Hello All,

The Traeger RTD Probe has  a higher temperature reading than my dome thermometer when cooking.  How do you interpret the difference?  Which temperature reading is the most accurate?  Any thoughts!

FredSG
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Bar-B-Lew

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #1 on: October 22, 2017, 02:06:26 PM »

Scrap both of them and use a grill temp probe that goes through a clip on the grate.  Then you will know your true grate temp and can adjust your controller appropriately to get to the grate temp you desire.
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MAK 2*, Memphis Elite, Traeger XL, Blaz'n Grand Slam, Pit Boss Copperhead 5, Weber Genesis II 435 SS, Sizzle Q SQ180

hughver

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #2 on: October 22, 2017, 02:36:56 PM »

I agree with Bar-B-Lew, however, on my Traeger Select, the dome thermometer (that I installed) tracks almost exactly to the pit RTD which tracks closely to the Tappeque grill thermometer.  ???
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--Hugh -- Sun Lakes, AZ. Traeger Select W/SS4, BGE-L, Charbroil Inferred Gas, Smokey Mountain Vertical Gas

FredSG

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #3 on: October 22, 2017, 02:52:37 PM »

Thanks guys,

I have a 1993 Traeger BBQ 100 - it's pretty old and I have done multiple upgrades.  My wife was concerned about the temperature difference . . .  Hughver, what DOME THERMOMETER DID YOU INSTALL?

Thanks again for your replies.

FredSG
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Jcorwin818

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #4 on: October 22, 2017, 03:27:12 PM »

I agree with Bar-B-Lew.  After ten years of cooking on my 075 Texas and monitoring my grate temp I know what to set my controller to to get the grate temp I want.
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hughver

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #5 on: October 22, 2017, 03:56:03 PM »

Hughver, what DOME THERMOMETER DID YOU INSTALL?

I installed these in both the DC and the Select. https://www.amazon.com/gp/product/B008N4AFI2/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
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--Hugh -- Sun Lakes, AZ. Traeger Select W/SS4, BGE-L, Charbroil Inferred Gas, Smokey Mountain Vertical Gas

Canadian John

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #6 on: October 23, 2017, 10:54:00 AM »

 The RTD is more accurate than the dome thermometer due to its location and being electronic. The controller is driven by RTD input.  At times the slower to react (mechanical) dome thermometer can read almost the same as the controller display. The pit must
"stabilize" for this to happen.

 The dome thermometer is a carryover from the days of the L/M/H or 3 speed controller..It was the only way short of installing a temporary grid thermometer to know what the pit temperatures were..That makes it a redundant device in todays world.

 If you continue to monitor the controller readout and the dome thermometer a pattern will develop indicating the more stable the pit temp is the narrower the gap between the two readings..

 In the end depend on the controller readout..
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ScottWood

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #7 on: January 22, 2018, 12:37:17 PM »

After a few years of cooking on pellet cookers I have discovered that if I let the "gunk" build up on the RTD probes my pits seem to run hotter and hotter than I would like.  I attribute it to the build up not he probes causing them to not be as accurate as they should be and the controller trying to make up for it.

I keep an old school oven thermometer on the grates of my cookers and have gotten in the habit of cleaning the RTD probes before each cook. 
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BMerrill

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #8 on: January 29, 2018, 12:10:24 PM »

The dome thermometer is a fancy hood ornament.
It only matches the RTD when the grill is cold... and maybe every once in a while when cooking.
 
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hughver

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #9 on: February 08, 2018, 08:07:28 PM »

The RTD ONLY measures the cooking chamber temperature and has nothing to do with temperature control in the grill.

What input does the controller use to adjust pellet feed?
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--Hugh -- Sun Lakes, AZ. Traeger Select W/SS4, BGE-L, Charbroil Inferred Gas, Smokey Mountain Vertical Gas

dshaffes

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #10 on: February 08, 2018, 09:22:01 PM »

How many degrees are two temps?
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Okie52

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Re: Temperature Difference RTD Probe & Dome Thermometer
« Reply #11 on: May 07, 2018, 06:21:32 AM »


On my Texas 075 smoker I have modified it with a Blaz n grill PID

Using a Maverick 732 my grate temps have been much closer to my dome temp than my RTD.

My RTD usually runs 30-35 degrees cooler than my grate temp with the maverick.  Dome temp is usually pretty close to grate temp.

Well now my PID crashed and I’m getting a Savannah Stoker so I’m anxious to how it performs.

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