Grid Temp: How to measure?

Buxwheat

I'm cooking a butt tonight for tailgating before the Dawgs game tomorrow. Decided to measure the grid temp and wondered if I'm getting an accurate reading. The Egg is set up for indirect using firebricks on the main grid and and a second grid placed on top of the end bricks turned on their sides (U-formation). I pierced a small potato w/ a digital probe and placed it on the grid right next to the butt. The temp readings I get are much lower than my dome temp: 230 on the grid probe vs 350 dome. After 8 hrs, the grid probe is around 245 and the dome at 325. Is this the right way to measure grid temp, and is it better to try to cook based on grid temp rather than dome temp?

Mike in Abita

I cook using the dome temp, unless I'm using the Guru. I think you are getting a false reading from the potato. Try clipping the grid temp to the grid without contacting the meat.

Grid usually will be 25-40 degs less than dome.

BTW 350 dome is a little high for smoking, though it should make for some good BBQ. Might find the cook to go a little faster than normal. More like an 1.25 to 1.5 hours per pound.

Slotmercenary

i clip my temp probe directly to the grid with an alligator clip for true temp reading. i don't pay much attention to the dome thermometer reading but that is just me. to each his own.......

Bacchus

I have had grid temps at 150deg lower than dome temp, with all devices calibrated twice.

I took AZRP's advice and decided "to hell with grid temp, just go by dome temp". I'n the end, it doesnt matter a whole lot.

Buxwheat

Just a bit higher than I usually do (250 dome), but I thought a grid temp of 235-245 was ideal, so I let it go figuring the potato-probe would be accurate. I'll try clipping it to the grid itself next time. I was trying something different because I thought the dome temp (as I was measuring it) may not be accurate due to the actual probe position/depth, air flow around the probe, etc.
Indeed the cook is going rather quickly: 9 hours now on a 6.5# butt and the meat temp is already 180. I figure in another 2 hr it will probably be done.
Go Dawgs!

Pyro

Grid temperature will lag dome temp during the heating period. First, the iron/steel takes longer to heat than air. Second, they have this cold chunk of meat resting on them and they are excellent conductors of heat.

Within one to two hours they should be virtually the same. Grids will also cool much slower than domes. During a low and slow cook, monitor the dome. It will reveal problems, should they exist, long before the grids react.

Grandpas Grub

Bacchus,

With calibrated dome thermometer, I have never had that big a difference. I have had +- 50° in the beginning of the cook then pretty close towards the end of a L&S cook.

If using the plate setter legs up I clip at least 2" away from any meat and over one of the legs so no direct heat hits the grid probe.

If legs down, I will have at least a 1.5" riser for the grid or I won't measure grid temp. Too close to the plate setter, or stone with the grid will usually give a wrong reading.

Very seldom will I clip the remote prove to the dome thermometer.

If one goes to the BBQ Guru Site there are some instructions for usig either the dome therm. or grid to attach the clip.

BBQ Guru has a probe stand. If you watch thirdeye's photos he has made a probe stand which places the probe up off of the grid. Both have different levels to attach the probe.

Your post gave me an idea to pick up a 1/16" x 4" bolt, wing nut and two large washers. Make a vertical probe stand that that I can clip on to.

GG