Temperature lower at dome than grate


 

GBurgess

New member
Anyone have issues with the dome temp on a 18.5 WSM being 30 degrees LOWER than at the grate? I'm running a CyberQ system with the pit probe at the grate, and my past several cooks have taken 1-2 hours longer than when I ran everything manually.
 
Lots of folks have that (as well as the expected higher in the dome than the grill). Just be aware of the uniqueness of your WSM and you're good to go.
 
When I got my new to me 22, the dome gauge was almost identical to my probe thermometer.
which apparently is rare. Now, it's full of water and I no longer even check it, :)

I like Thermoworks DOT probe thermometer for grill temps, and have another one for meat temps.
 
I had the same phenomenon in my rib cook on Saturday (albeit with my WSM22.) I think there are just variations between temps at different spots in the cooker, these can be affected by what you have in your pan (water, sand, nothing?), how much meat you have loaded and where, thermometer accuracy differences, weather, etc. My general practice has been to use a single measurement as my guide for cooking, but even then, there are so many variables that nothing replaces your vigilance and experience when judging when something is done, or has to change during a cook (meat placement, temp, etc.) All of my copious notes about temps, times, etc, become just general guides as no two cooks will ever be the same.

R
 
I have the same thing occur. I don't really rely on the dome thermometer. I use a remote at the grate level. I agree with Rich about all the variables that can effect the temp reading as well as the actual cook itself. Like Rich I too keep notes of each cook. More to help me develope my process as well as seeing how different conditions such as temp, humidity, wind, all of which I record, can effect any particular cooks process.
 
The dome thermometer is notoriously unreliable and it does change over time as goo builds up on it, etc. A remote probe at the grate is the best solution, but if you don't place it in the same location for each cook, you might also get inconsistency.

Jeff
 
Anyone have issues with the dome temp on a 18.5 WSM being 30 degrees LOWER than at the grate? I'm running a CyberQ system with the pit probe at the grate, and my past several cooks have taken 1-2 hours longer than when I ran everything manually.

I'm thinking I will try adding a second pit probe clipped to the inside of the dome thermometer and then average the temperature with the grate probe. Anyone ever try this?
 
My pit probe sits below the top grate, about an inch inside the middle section.
My water bowl is always empty but covered in aluminum foil.
As such, my pit probe never has to content with the influence of water in the pan nor the temperature of the meat.

If the "fire" is lit and there is no meat on the top grate, my dome thermometer matches the temperature of my pit probe.
If the "fire" is lit and the meat on the top grate is almost up to temperature, my dome thermometer almost matches the temperature of my pit probe.

If the "fire" is lit and the meat on the top grate is cold, my dome thermometer shows a far lower temperature than my pit probe.

Why is this...
Because that heat energy that was added to the air inside the WSM by the hot coals was partially absorbed by the cold meat. ( Otherwise, the meat would never cook ! ) So, there is more heat energy in the air as it passes by the pit probe than there is when it passes by the dome thermometer. (and less heat energy as it passes by the dome thermometer than it did when it passed by the pit probe.)

YMMV... depending upon if you run water and where you placed the pit probe.
 
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It is frustrating isn't it?

But, here's the question - how and where is everyone measuring temp "at the grate"?

How close is the probe to the meat? Or is the probe tip in the gap between the inside wall and the water pan below?

I've kept spreadsheets of this and I've found that the temps at the grate can be lower than the lid (like when doing a large butt that is still cool from the fridge which will act like a cool 'sink'), or it can match (later on in a cook as the meat is coming up to temp), or even higher than the lid (when the probe tip is in that gap and is directly reading the heat being deflected by the water pan and up the inside gap).

I've let go of obsessing about a +/- 10degree variation in my target temp or whether the grate is hotter than the lid (it varies from what I've kept records for).

Larger cuts I will use a constant read meat probe, but am taking the advice here; it's ready when it's ready.
 
It is frustrating isn't it?

But, here's the question - how and where is everyone measuring temp "at the grate"?
How close is the probe to the meat? Or is the probe tip in the gap between the inside wall and the water pan below?

Larger cuts I will use a constant read meat probe, but am taking the advice here; it's ready when it's ready.

Standard clip that comes with the 732 sets the probe about 1" above the grate. I use that plus try to keep it a minimum of 2" from the meat (IE: as far as possible).

Dont sweat 10-20o difference . I only use the dome thermo to guesstimate WSM temps. I rely on my 732.
 
I use a wood clothespin with two holes drilled for the probe in the "squeezie" part, lol, yeah I'm that cheap.
I clamp it so the probe goes between the meat a few inches in from the edge, above the water pan so as not to get a false reading from heat coming around the pan.
But, it's just to get a ballpark temp for that cook. As long as it's consistant and around where I want it, we're good to go.
 
I use the factory clip I keep it away from the meat and I try to put it in about the same place on the grate each time so I can get the same basic heat flow, so I can build a cook time based on as much reapetable info as I can get.
The dome I use just to monitor heat rise when I start the smoker gives me a point at which I adjust the vents and stabilise the temperature before putting on the meat and true temp probes for grate and food.
 

 

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