Maintaining Temperature

OshawaDave

I cooked a roast chicken yesterday on my BGE and I had trouble keeping the temperature below 400 degrees. I calibrated the thermometer and it is correct.

I filled up the fire box with Royal Oak lump charcoal and used the plate setter for indirect cooking. I let the fire stabilize for about 40 minutes. Even when I dampered down the bottom vent to almost closed I was still at 400 degrees. The bird was fine, it just cooked sooner than I had anticipated.


I am planning on slow cooking some back ribs next weekend and need to figure out why I can't get the temperature lower. 

Any thoughts form the experts are welcome? 

lousubcap

Sounds like it could be air leak (but if post-cook it shutdown fine then that can be ruled out).
Did you get a large quantity of lump initially burning and then try to control the temp and dial in a lower temp?  If no air leak with those vent settings, then you must have had too large a fire.  Have you been able to run at lower temps previously?  As you know, the BGE is an air-flow driven machine (if you have adequate fuel and an ignition source).  
BTW-welcome aboard and enjoy the journey.  Above all, have fun.   

pgprescott

Once the ceramics heat up to a temp, it’s pretty much game over. You prolly let the fire get a little too big prior to closing the vents down. Hard to say. 

OshawaDave

It shut down fine, so I'm assuming no air leak. I've been filling the fire box full with charcoal each time I use it. I cooked a prime rib two weeks ago and couldn't get it below 375. And you're right, it was a hot fire.


Perhaps I shouldn't be using so much coal for a 2 hour cook? 

Eoin

Volume of lump isn't the issue. How hot did it get before you shut the daisy/vent? If you are at 400 F and then reduce the settings it will take a while to come down.

ColtsFan

Choke it back sooner. Like mentioned above, its hard to get temps down once she gets rippin'. 

MattBTI

This would happen to me when I was relatively new to the egg. To better understand, is the temp creeping up higher and higher, even when dampers are almost closed? When you say stabilize, are you getting the egg right to your target temp then setting vents? If so, you will always overshoot. 

OshawaDave

MattBTI said:

This would happen to me when I was relatively new to the egg. To better understand, is the temp creeping up higher and higher, even when dampers are almost closed? When you say stabilize, are you getting the egg right to your target temp then setting vents? If so, you will always overshoot. 

The temp is not creeping up once stabilized and the vents adjusted. I've been letting the fire get going  up to maybe 500 and then starting to dial it back. I just can't seem to get it down below 375-400.

I've been afraid to start dialing back when it hits my desired temperature, as I feel the fire will smolder and give me that awful smoke taste.

pgprescott

Definitely shut the vents down sooner. You don’t want the temp to get up to the desired temp let alone over it. If you want 250-275 you better start dialing it back at 200 or less 

Woodchunk

OshawaDave said:

MattBTI said:

This would happen to me when I was relatively new to the egg. To better understand, is the temp creeping up higher and higher, even when dampers are almost closed? When you say stabilize, are you getting the egg right to your target temp then setting vents? If so, you will always overshoot. 

The temp is not creeping up once stabilized and the vents adjusted. I've been letting the fire get going  up to maybe 500 and then starting to dial it back. I just can't seem to get it down below 375-400.

I've been afraid to start dialing back when it hits my desired temperature, as I feel the fire will smolder and give me that awful smoke taste.

If your target is 400 then I would start dialing back at 350 or sooner. Put some lump in the egg and light it off without food and practice

Eoin

If you are getting 500F on the dome with the platesetter in, thay means everything in the Egg is hot. You have a lot of ceramic to cool down and you are still running a fire, albeit a small one. If you light the fire in one spot with vents fully open and wait for the smoke to clear / glowing lump, close to what you show on your picture and walk away for an hour, likely you will be stable at between 250F and 275F.

Experiment like this and once you have it nailed, you can practice faster starts.

MattBTI

I've found that a guy has to get the right fire going for the desired cook. I start my fires with a starting square for anything under 350F or so. If i'm cooking hotter than that I get out the weed burner. 

kl8ton

You will need to try to catch it on the way up.  When it looks like a baseball sized amount of lump is glowing, close the dome and set the vents.  You may be at 250 or so. Watch it creep up from there.  From what you are describing, I would guess about 75% of the coals on the top surface are glowing hot.  Also, using the daisy wheel AND the lower vent to try to control temps just complicates things.  If you want to be over 300 or 350, the daisy wheel can be removed.  If under that temp, keep it on with the small holes, full open and use the lower vent to control temps.

OshawaDave

kl8ton said:

You will need to try to catch it on the way up.  When it looks like a baseball sized amount of lump is glowing, close the dome and set the vents.  You may be at 250 or so. Watch it creep up from there.  From what you are describing, I would guess about 75% of the coals on the top surface are glowing hot.  Also, using the daisy wheel AND the lower vent to try to control temps just complicates things.  If you want to be over 300 or 350, the daisy wheel can be removed.  If under that temp, keep it on with the small holes, full open and use the lower vent to control temps.

Yes, the fire was glowing. Perhaps part of my problem is closing the dome too soon.

Great suggestions from all. I'll try to catch it on the way up and see if that works.

jtcBoynton

The picture you showed for "Even when I dampered down the bottom vent to almost closed I was still at 400 degrees" isn't  really closed down enough for low temps.  That opening is about 3 times larger than I sometimes use for low temps.  One, two, or maybe three sreeen grids is all you need (varies with weather conditions).

SoCal_Griller

Here is a good read on controlling heat with airflow.
http://http//www.geekwithfire.com/Articles/TheBasicsManualTemperatureControl/tabid/77/Default.aspx

"Temperature in you cooker is directly affected by volume of ignited fuel and the amount of oxygen feeding it. "

Notice the article mentions  volume of ignited fuel.
So for a low and slow, don't let the amount of ignited fuel get to large otherwise it's like riding a pissed off horse.