Dome vs Grate Temperature


 

Bob Mann

TVWBB Honor Circle
I did a couple of racks of spares tonight.
http://tvwbb.com/eve/forums?a=...001064046#5001064046

My target temp was 275F.
For much of the cook, my stock Weber 22 1/2" WSM dome thermometer read about 50F lower than my ET-732 pit probe at the grate. I tested the Maverick with boiling water, it's calibrated.

Don't trust your dome thermometer.

Weber dome thermometer.
spareribstemp12.jpg


Maverick ET-732.
spareribstemp11.jpg


Bob
 
Have you tested the dome thermometer for accuracy?

I would not expect the temp to be the same in two different locations. Both measurements could be right.

I've given up trying to understand the differences between temps at various locations in the WSM. There are just too many variable going on inside the cooker.

Regards,
Chris
 
To be sure, I checked both thermometers in boiling water.
The WSM thermometer is held in with a wing nut, which was hand tight and came right out.
The WSM reads a bit low at 208/9F, the ET-732 is dead on.

Chris, I agree with you that the temperature will be different in different locations in the cooker, wildly some times, which bolsters my original post, "Don't trust your dome thermometer."

The stock 22 1/2" WSM.
mmspicture13.jpg


The Maverick ET-732.
mmspicture14b.jpg


Bob
 
Implicit in your comment is that grate temp is more valid than lid temp when cooking. I know this view is becoming "gospel" among many experts on the web. I don't buy it. I'm happy to measure only at the lid and don't measure at the grate anymore. Have not done so for years, as I've simplified my approach and never use probe thermometers anymore in meat or on the grate. I'm barbecuing old-school and my food turns out great anyway.

Don't get me wrong. I'm the kind of guy who says, "do whatever makes you happy, do whatever makes sense to you". But I do like to let people know, esp new people just starting out, that there's an alternative view on the gospel of grate temp and it's ok to measure only at the lid and you'll still get great results.

The analogy I always like to offer is your home oven. Temp is measured not at the rack, but in the top right corner. Ovens are notoriously inaccurate when it comes to temp, yet somehow people use them successfully to prepare meals everyday all over the world.

Can you measure temp at the rack? Of course, but only the most serious cooks do that. The vast majority of home cooks do not. Instead, they get to know the idiosyncrasies of their ovens over time and make good food anyway. Same can be true with your WSM or any other brand of cooker.

Sorry for the long reply!

Regards,
Chris
 
Great insights, Chris.

As great as the "ideal" of cooking at the grate sounds, it isn't always too practical, especially if cooking on a 18.5" wsm. Start-up temps are GREATLY affected by cold meat next to a therm, and it's always hard to put your probe tip in the same place every cook, ie. a big brisket one cook with the probe tip almost in the outer perimeter hot zone, and then dead center between two butts next cook.

In my opinion, there's downsides to anyplace you might decide to measure temp, but there's a lot more to cooking than that, so it's no big deal once you learn your cooker. I'll often just go with the Weber gauge, at least for shorter cooks. Works for me, and since your gauge is accurate within 5*, it'll work for you as well.
wsmsmile8gm.gif
 
Yes Sir.
icon_smile.gif


A buddy of mine recently sold me his, with the extra top vent and middle grate mod, as well as as handles for the middle section and coal grate. While my wsm has been more than adequate for most cooks, I feel like I can handle most anything thrown at me now with the big WSM. Best thing is how quick I can get up to temp, and that makes for more regular and predictable cook times.
wsmsmile8gm.gif
 
I've played with a Tel Tru therm, the Weber dome therm my turkey fryer therm and my Maverick. It's kinda like having too many cooks in the kitchen! As an example hang the Maverick probe just through the dome vent. Take the temp. Lower it 6 inches and take the temp. I have found the temps vary between the dome and the grills and that variance can change throughout the cook.

Other than my meat probe I have decided to pick one device, keep in the same location and use it as my reference point for my cooks.
 
Originally posted by Gary S:
I've played with a Tel Tru therm, the Weber dome therm my turkey fryer therm and my Maverick. It's kinda like having too many cooks in the kitchen!

Preach it!
wsmsmile8gm.gif
 
This topic keeps coming up and, for me, I'll keep preaching as Chris says. You want to know what your WSM is doing but it really doesn't matter where you take the measurement -- or what the various temps are. As Dave said, the grate temp will be TREMENDOUSLY affected by your meat temp. And the same applies for almost any other location temp, though proximity to the meat is a major factor.

I have "too many cooks" I've "thrown all out" except the resident "cook" . That would be me and my WSM therm. Why? Well my recently added Thermapen inserted through the vent just added a plethora of new opinions. Great thermometer and it really tells how the temp in one location can can vary a lot.

The the hood therm is the master. My Maverick lets me work in my shop or watch a game or go to bed knowing that a BIG issue will be picked up. Otherwise, why do I care? This forum is filled with posts about the reliability of the WSM -- and over my "vast" two years of experience with it, I have come to trust THAT judgement just like I trust the hood therm.

Incidentally, if ANY thermometer is to be doubted, for me it is the Maverick on the grate. Not exactly conducive to a relaxed smoking environment.

Rich
 
Chris, your approach sounds like mine. Just bought a new 18 1/2" after years on the standard Weber kettle. Tried ribs last night, they were good, but maybe a bit dry. I did not marinate them beforehand, but I did use a dry rub and let them sit for an hour at room temperature. They were on the grill at least 4 hours at about 250 dome temp. Any suggestions on ending up with moist ribs? Thanks, Jim Schulte, St Louis, Mo
 
Implicit in your comment is that grate temp is more valid than lid temp when cooking. I know this view is becoming "gospel" among many experts on the web. I don't buy it. I'm happy to measure only at the lid and don't measure at the grate anymore. Have not done so for years, as I've simplified my approach and never use probe thermometers anymore in meat or on the grate. I'm barbecuing old-school and my food turns out great anyway.

Don't get me wrong. I'm the kind of guy who says, "do whatever makes you happy, do whatever makes sense to you". But I do like to let people know, esp new people just starting out, that there's an alternative view on the gospel of grate temp and it's ok to measure only at the lid and you'll still get great results.

The analogy I always like to offer is your home oven. Temp is measured not at the rack, but in the top right corner. Ovens are notoriously inaccurate when it comes to temp, yet somehow people use them successfully to prepare meals everyday all over the world.

Can you measure temp at the rack? Of course, but only the most serious cooks do that. The vast majority of home cooks do not. Instead, they get to know the idiosyncrasies of their ovens over time and make good food anyway. Same can be true with your WSM or any other brand of cooker.

Sorry for the long reply!

Regards,
Chris

Amen! This gospel seems more apocryphal to me then true ;)
 
I tried to measure the differences in dome vs grate temps and found them to be fairly close the few times - used an oven thermometer sitting grate level for the test, but these things can vary so much it's hit or miss anyways, or so it seems for a lot of people that have posted.

However, I think the most important things are just getting familiar with your own smoker, experimenting cooking with differing levels of heat (after all, temps will vary a bit anyways no matter what we do), and becoming comfortable measuring doneness of the meat - it's supposed to be fun BBQ'ing after all! BBQ cooked at 225 is just as delicious as 275 or 300 as long as it is pulled at its peak juicy/tender/delicious point. Timing is often a factor for the start, but like I said, getting comfortable w/your smoker will allow you to speed up or slow down the cooking process as needed. Just my personal take.
 
Hmm, I'm running against the current here. I don't have a WSM yet, but I have a Weber Kettle and I started out measuring both the dome temp and the food grate temp. I used a Thermoworks k-type unit that is pretty accurate. I don't bother with it much anymore, but it was handy while I was figuring out what was going on in there. Now I use a Thermoworks kitchen probe at the food grate. I want to know what the temp the food is experiencing. If I was forced to measure at the dome only, no problem, I know it runs 30F to 50F higher than my food grate. If I had a bimetal thermometer, once I had verified what it reported, it would be just like my oven and I could estimate what was really happening. But in general, I'd rather know the temp at food level than someplace else in the smoker/oven/whatever.
 
I have a Pitmaster IQ-110. I now use that and pay no attention to the Weber Therm. But before I got the IQ I used the dome. My BBQ always came out fine. As some old time BBQ Boy once said: "Don't sweat the small stuff!"
 
I come from the 'Don't Fuss Too Much Over BBQ' school of thought. When I see the dome temp at 200-225, I know I'm good. I
know some folks are into taking temps from the dome, grate, middle of the smoker, edge of the meat, center of the meat, water pan temp, etc. If it works for you, cool. And I understand how that's part of the fun for some. I just can't be bothered. My 'No Fuss' method turns out perfect BBQ every time, no complaints, demands for more.
 
This thread or those like it come up all over BBQ forums daily. I've probably done like most of you and quit fussin with with it. You just realize it's BBQ and is very forgiving. I don't even use an auto temp controller anymore on any of the cookers. After a while, you realize that once the vents are set and the temp locks in, it stays in a range, rising and falling, for hours on end. Because I don't have a probe on the kettle or mini-wsm, and because I have a mav, I must admit I do use it in all the cookers so I can set the alarms in case any issues ever do come up. ... it seems like they never do. I have a buddy that doesn't use temp at all until he gets to a certain time in the cook and he uses a themapen looking for a target temp. He's very confident and used to his equip.
 
Good thread to read for a noob like myself and a Maverick ET-732 first time user. The grate probe does appear more sensitive to environmental factors (placement, meat temp, lid openings) and the instant read could compel a user to make premature vent settings. Cooking in general is more forgiving. The internal and grate probes provide more situational awareness; for now I will use the the lid temps to make any vent changes and measure over 15-30 minute periods.
 
I use a Pitmaster IQ-110 controller which is great for long cooks and allows me to not "hover" over my WSM. But before I got the IQ, I just went with the dome and food turned out great. Temps almost always stayed within 30-50 degrees of what I wanted. And I think given the fact that we're working with a live fire, the temps are gonna move around a bit. If my pit stays within the gray or smoke area of the WSM dome, I'm happy with that...

Today I'm cooking a 10.5lb pork butt. The Pitmast IQ, clipped on to the cooking grate, is set and holding at 250*. The dome is holding steady at 210*. I can live with that.

WSMDome210.jpg
 
Last edited:
Like I suspect many here did, when I first got my WSM I was comparing temperatures at grate level to dome therm and as time went on I stopped worrying about it.
I did notice last weekend with the Auber probe clipped to the grate and a welding blanket draped over the smoker that the Auber and the dome thermo were within a few degrees of each other. It is not normal for them to be that close, I'm guessing it was the welding blanket holding in the heat that evened things out.
 

 

Back
Top