Grate Temperature vs Dome Temperature

[John Setzler]

Here's another question that I get asked frequently:

 

Hi John
I was referred to you by [source deleted]. I’m very new to cooking with a KJ so trying to learn quickly.

Most recipes call for cooking at a certain temp, presumably as shown on the KJ thermometer. Recognizing that the temp at the grate level is typically hotter by 20-50 degrees than the dome temp (which is what the thermometer is measuring ). Does the suggested cooking temp take into consideration this variation.

I’ve heard that there’s lots of debate on the internet about this subject. Some suggest using a monitor that registers grate level temp. If so, how does one reconcile with the recipes suggested cooking temp.

All the best,

[Name removed]

 

***********

In all MY cooking and in my recommendations to others, I use the dome temperature. The dome temperature is the most consistent temperature reading inside your kamado grill. On the occasions where I use temperature controllers to operate my grill, I still use the dome temperature as my reference. I normally clip my electronic grill temperature probe directly to the stem of the dome thermometer so it will be as close as possible. If I am unable to do that for some reason, I use the temperature controller to make my DOME thermometer read at or near my desired temperature regardless of what the digital temperature at the grate reads.

 

Electronic probes placed directly at grate level will be inconsistent for many reasons. There are a few specific reasons that these readings are inconsistent. Electronic probes placed close to food on the grill will actually be cooled by their proximity to that food. Electronic probes placed too close to the outer edge of the grill will be heated by the hot air rising from around the heat deflectors. Food dripping grease or condensation on your probes will make their readings inconsistent. Finding the perfect balance of this can be tricky and will always, in my personal experience, be rather inconsistent. For ME, consistency is a higher value target than accuracy. 20 to 50 degrees variation at any given time in the grill is not going to make or break your cook. If it would, a majority of my cooks would be failures since I pay zero attention to any temperature at the grate level.

 

When cooking over heat deflectors, the temperature variations you see between the dome thermometer and the grate temperature will normally stabilize and normalize when the when the lid is left closed. Frequent lid opening will keep these two readings well apart from each other.

 

One part of being a successful grill chef is being able to tell when the food is done. Grills are, by nature, not as consistent as the average indoor oven. But Kamado grills and other computer controlled grills are challenge that idea very nicely most of the time. Your hands, eyes, and taste buds are more important tools for determining a successful cook than your thermometers and timers. Use these tools as reference only to get you CLOSE to the target. Use your human five senses to get you across the finish line 

 

Cheers and enjoy cooking on your grill!

[pmillen]

FWIW, on my Big Joe I use a stoker with the controller probe at grate level, close to the food (sometimes on a toothpick stuck into the food).  The stoker thermometer and the dome thermometer track.  It may be due to the stoker’s convection oven-like air movement.

 

I understand that the cool food is cooling the temperature probe.  That’s because it’s cooling the air surrounding the food.  But it’s exactly that air temperature that I want to control, not the air in the chimney.

 

BTW, most temperature differences or fluctuations don’t concern me.  The food’s internal temperature tells me when it’s done.  I'm really only interested in close temperature control as a way to estimate completion times in order to coordinate side dishes.

[Shocker]

I was dealing with this today. Bought the maverick X-r50 and used for first time today. Cooked 2 racks of ribs. Tried to dial dome to 250 grate temp . When I hit 230 I put the ribs on and watched it slowly climb. Problem was it never quit. Even when I put the brakes on it. I ended up taking another probe and putting at opposite side of rack. Temp was 50 deg hotter! Thought it was a fluke so I put a Weber temp probe through the gasket near one of the probes and it matched the Mavericks readings. The gauge on the dome never went above 250 and I had the bottom vent open about an inch and the top setting on about the second line (classic 2). A lot of head scratching and a few curse words later I’m not sure what was happening. Gasket was sealed tight. The above answer makes sense though. But why would I read about all these guys advising to set a probe on grate and one on meat??? I’m new to grilling/smoking so this was kind of frustrating

[Shocker]

Also the dome gauge was a lot lower 

[JohnnyAppetizer]

I have a Traeger pellet grill. Nothing fancy. Small Costco road show model.

The temperature can vary as it cycles. Set at 225, may be 200 or 250, depending on a variety of conditions. Overall the average is probably close to 225. I use a meat probe to dial in the final temp. I rely on that and experience regarding the end result of the cook.

 

My limited experience with the Kamado Vision is much the same, I try to dial in the dome thermometer, and it may move up and down a little during the cook. Towards the end of the cook, I am looking at the meat probe, maybe some additional testing with a instant probe Thermopop. Some shooting from the hip,  what I think is going on with the meat from past experience. 

 

 

 

[K_sqrd]

So... How did the ribs come out? A couple of thoughts... Placing the probe at the grate level can give

readings all over the map. The reasons are:

> Most Kamados cook hotter towards the back of the grill compared to the front.

> If the temp probe is placed next to cold meat on a hot grill, the cold meat will influence the reading.

> The grate temp will always (almost always) be hotter than the dome temp because the grate is closer to the coals.

>  Items like brisket, ribs, butts, etc. cooked on a grill can be done somewhere between 225 and 350 deg. F  and turn out fine.

 

Personally, I use the dome temp and have for years. It's a constant and reliable. Read John's posting above. Good advice.

 

Welcome to the forum!

[fbov]

It's about location. 

 

The dome thermometer is intended to give you a good idea what's happening under the lid, an average temperature. I've placed probes in a lot of places, and sometimes the dome reads the same, sometimes not. 

 

Look at the air flow in your Kamado. Hot air comes off the coals, rises and is deflected to the perimeter of the heat deflectors. Put a probe above the edge of the deflectors and you'll get an abnormally high reading. Put it in the gap between fire bowl and outer shell, and it will read lower, because cooler air is being pulled down around the fire bowl to feed the fire. 

 

Inside the perimeter of the deflector, this air circulation gives you a region of quite uniform temperatures. I just cooked two ~5 lb. brisket flats using the extension grate to put them above one another near the center of the grate. They were within 1 degree at 160 F and 3 hours.

 

Conversely, I've also cooked 45 lb. of brisket - five 9-pounders - which pushed meat right to the edge. I started fat-cap-down, and the meat at the perimeter was GB&D, golden brown and delicious, because the fire was running 300+ at the edge while the dome read closer to 200 F. It's hard to get things hot with that much cold food on the grill. 

 

My recommendation is to always put a probe in the exit vent. I find it invaluable for monitoring the status of the fire because it responds to temperature changes before the other locations. I did this on my offset smoker, and find it's not much different in a Kamado; after a few hours, 250 F exit is 225 F between the meats and the dome's reading 225-235. 

 

Have fun,

Frank

 

PS get the fire outside; you're on the wrong side of the garage door. 

[JohnnyAppetizer]

FYI, this is some Italian lemon chicken I made tonight. I like Greek chicken, but I saw this recipe on Milk Street, it's grilled, not baked. I hope Cristopher  Kimball does not have a lactose induced attack, I used boneless skinless chicken. Anyhow, the grill is a small (18) kettle I bought at Lidl last year, It's at my GF's house. Note, no dome thermometer. I did check with a thermopop. mostly fly by the seat of your pants. You can spend a lot of money on your hobby, and you can agonize over every detail, but you can relax and stop worrying, just start cooking.

[T_om]

I'm surprised to hear that John relies on the dome thermometer in this day and age of very good remote digital thermometers.  Different strokes for different folks... but every dome thermometer I have ever owned was, not to put too fine  point on it, crap.

 

That is not to say the dome units are not "usable"... they are just not "accurate".  I used them for years, with a caveat.  EVERY one needed to be used based on experience gained by good and bad cooks using the indicated temperature until you learned EXACTLY what was going on inside the grill with the dome thermometer pointing at apparently random numbers.

 

Indeed, all dome thermometers I have ever seen would be just as useful with no "temperature' scale markings at all... just a dial with markings from 1 to 100.  After getting some experience with it, you would just cook chooks at about 7, indirect low and slow at about 2,  hamburgers at about 6, etc.

 

Nowadays I know the grate temp and am a happy camper.  Not all tech is good tech.  But I love my digital thermometers.

 

Tom

[John Setzler]

1 hour ago, T_om said:

I'm surprised to hear that John relies on the dome thermometer in this day and age of very good remote digital thermometers.  Different strokes for different folks... but every dome thermometer I have ever owned was, not to put too fine  point on it, crap.

 

That is not to say the dome units are not "usable"... they are just not "accurate".  I used them for years, with a caveat.  EVERY one needed to be used based on experience gained by good and bad cooks using the indicated temperature until you learned EXACTLY what was going on inside the grill with the dome thermometer pointing at apparently random numbers.

 

Indeed, all dome thermometers I have ever seen would be just as useful with no "temperature' scale markings at all... just a dial with markings from 1 to 100.  After getting some experience with it, you would just cook chooks at about 7, indirect low and slow at about 2,  hamburgers at about 6, etc.

 

Nowadays I know the grate temp and am a happy camper.  Not all tech is good tech.  But I love my digital thermometers.

 

Tom

 

I think my original post in this thread is a great explanation of why I prefer the dome thermometer.  My desire for a consistent temp in my grill from cook to cook is significantly more important to me than an accurate reading from any one point on the grill grate.   That grill grate point may be 'accurate' but if you notice that it won't coincide with the dome thermometer you will start to understand my point.  If you compare it across several different cooks you will also see that one time your grate temp will be higher than the dome temp.  Another time it may be lower.  Another time it may be the same.  While it may be 'accurate' its just not consistent.  

 

My cooking skills and results improved dramatically when I quit relying on technology for my answers.  A digital instant read thermometer is the primary piece of technology involved in cooking that I would not want to give up.  That piece of technology makes me more consistent with my results.  There is no guessing or wives tale technique for knowing when your food is done.  

 

I love temperature control systems as well.  I am beginning to preach the gospel on how useful those are.   They save me time.  

 

Quote

That is not to say the dome units are not "usable"... they are just not "accurate".

 

 

I have experimented with this FAR MORE than most people have ever considered.  I have multiple electronic thermometer systems....

 

DigiQ 2 DX

PartyQ

Flame Boss 200

Flame Boss 400

iKamand

Fireboard

 

Thermoworks TW8060

Thermoworks Smoke

Thermoworks Signals

Smoke Bloq

iGrill

 

I am probably actually missing some on this list..   I have spent more money on electronics than most have spent on their grill and electronics combined.  That's over $2000 I have spent right there and I also excluded the price of the iKamand and the Smoke Bloq since I got those for free.  

 

Quote

I'm surprised to hear that John relies on the dome thermometer in this day and age of very good remote digital thermometers. 

 

With everything I said and listed here, you should seriously ask yourself WHY I would rely on my dome thermometer.  You will come up with one of two answers.  1 - He's a complete idiot.  2 - He's on to something.  Maybe I should figure out what it is

 

[fbov]

2 hours ago, John Setzler said:

He's on to something.

My vote. The only problem I have with dome thermometers is location... my location when reading it. 

[John Setzler]

36 minutes ago, fbov said:

My vote. The only problem I have with dome thermometers is location... my location when reading it. 

 

True.. in the modern world we can't be bothered with walking out to the grill occasionally to see what's going on

[keeperovdeflame]

58 minutes ago, fbov said:

My vote. The only problem I have with dome thermometers is location... my location when reading it. 

Here's a little trick to help with that. Step 1. remove the clip that holds your dome thermometer in a fixed position. Step 2. once the thermometer is able to turn, simply turn it so your target temp is straight up at the top of the dial. Step 3, now you can see your temp and it's progression by the angle of the needle on your thermometer without being close enough to see or read the numbers. If the needle points  straight out to half way up the left side of the dial, you are half way your target temp, if it points straight up, you are  on your target temp, if it points to the right of straight up, you are over your target temp. Using this technique, I learned from Ck Reef, I can read my thermometer while sitting on the couch watching football and looking out the window at my grill, or while looking  out the kitchen window while doing prep work. Once you work with this a bit, you can tell the "spot on temp" just by the angle of the needle without being close enough to see the numbers. In addition to using this technique, I purchased a 3" dial from TelTrue which is much easier to see from a distance. Old School Cool 

[K_sqrd]

41 minutes ago, fbov said:

My vote. The only problem I have with dome thermometers is location... my location when reading it.

I read of one fellow faced with that situation when attempting to do a long cook while he was at work. His

solution was to set up a video camera focused in on the dome thermometer. He then connected the camera

to his computer. While at work, he simply logged into his home PC and viewed the the dome temp. Sort

of redneck high tech, but it worked.

 

As for dome temps, make sure that the dome  thermometer is accurate, if not replace it. They are not

expensive and work very well in keeping track of a cook.

[ckreef]

Like @keeperovdeflame   explained swivel the thermometer so target temp is straight up and down. That was my old method.

 

I now use my Thermoworks Smoke or my Thermoworks ThermaQ devices. But not at grate level. I removed my standard dome thermometer and put the digital probe in the dome thermometer hole. I use either a slice of a wine cork or some foil to keep it in place depending on the grill. Nice accurate digital reading in the dome that I can take in the house with me. I even have this setup for my Wood Fired Oven. Single best upgrade I did to my grills.