temperature stabilization

CSILVA1129

Hey all! I've had the large egg for about 3 months now and have smoked quite a few times already. As I'm typing my egg is lit and starting up. I have issues getting the egg to start up and maintain temperature. My egg right now has fogo lump with hickory chunks and a little pecan chips sprinkled on the top. I do have a drip pan on the plate setter with water in it and some apple cider vinegar. Normally i don't use water in the drip pan but my pork butt was boneless because last minute i couldn't find one bone in. However my issue remains with or without water. So onto the problem. I get it started and warm it up to about 230 degrees wide open. Once I dial in the vents to try to get it to maintain 250 my temp drops like 100 degrees to about 137. I wait about 30 minutes and the temp still won't climb back up to 250 or within a few degrees. I open it up again and get it to 240 and then dial it down and it begins to level off and hit 250 for a good 3 minutes. Then the temp drops again to 237 and doesn't wander it's way back up. Right now I have it relatively close but I never get spot on temps and it's always a fight. Am I not patient enough or am I doing something wrong?

Note that my estimate for 250 is the daisy wheel a little less then half open and the bottom vent about an inch and a half ish.

Any help greatly appreciated!

Chris

lousubcap

Welcome aboard and enjoy the journey.  Above all, have fun.
As you know the BGE is an air-flow driven machine.  The volume of air dictates the size of the fire and thus the cook temp.  First up-is your dome thermo cal checked in boiling water? 
Your vent settings seem excessive for about 250*F but if the thermo is good then that's what they are.  Also, most bGE's have a sweet-spot somewhere in the 240-260*F range where they settle in.  This is an analog operation not digital.  If you are within +/- 10-15*F of your target temp, close enough.
The water pan-not needed for moisture or temperature control.  It acts as a heat sink as long as you have liquid in the pan.  Should the liquid evaporate then your temperature will increase to the wherever the non-pan vent settings will take it and then stabilize there.  FWIW-
A question-you mention 230*F wide open.  Can you expand on "wide-open"?  Most here start with the dome open, bottom vent full open and wait til they get some quantity of lump burning (about soft-ball sized for a low&slow cook) before closing the dome.  

Legume

Don't fret 15 degrees either direction unless you're trying to run really low.  I can't say that I've seen my egg drop temps like that, but if I'm trying to set at 250 or below (what I would consider low temps) then I usually adjust the vents several times on the way up, ease into it rather than just try to hit the mark in one adjustment.  Make smaller adjustments on the way up, see if that helps.  270 is the new 250.

Carolina Q

This is @Grandpas Grub's pic of what he uses for 250°.
That's about what I use as well. If I leave it wide open until it reaches 220° or so, and then shut it down to this, it stabilizes at 250° or so.

CSILVA1129

Thanks for the response! I do have a dual probe meat thermometer that was tested with boiling water and one probe is measuring done temp. Normally I don't use a water pan but I figured if the butt was boneless maybe it could add some moisture but for sure next time I'll do without. So when I fire it up the dome dome open and the bottom vent is open all the way until I get a good coal base going. Once that happens I close the dome and leave the bottom vent open and daisy wheel slid open. So what I mean by wide open is the daisy wheel is slid open completely and the bottom vent is slid wide open. This to let the temp rise close to where I want it to be and then I dial down the vents to start to slowly rise and not overheat. But it never usually works that way haha.

gdenby

You should be getting a hotter fire w. those vent settings. I'd expect at least 350. Is the fire box bottom hole lined up with the vent door?

Less likely, you may already have a lot of ash build up around the bowl below the holes. Myself, I need to take all the inner parts out about every 6 months and clean away ash, bits of lump and chips, or the heat won't hold at 250 w. ordinary vent settings.

How are you starting the fire. Early on, I used fire cubes, and had similar temp drops. The cubes produce an open flame that heats up the top of the dome around the thermometer, but the body of the Egg isn't warmed much at all. The 'setter absorbs lots of energy. Eventually, it will be about 600F if legs up. So it needs a pre-heat also.

Sometimes, if the Egg has been out in lots of rain, the ceramic is saturated w. moisture. I've had a few cooks where it took me over 2 hours to reach 250 'cause the ceramic was so wet. Most of the fire was just just baking that out.

reinhart36

Howdy!

What method are you using to light your charcoal?

Perhaps your initial temperature is being driven more by heat from that, and less by charcoal actually being properly lit.?

CSILVA1129

@gdenby I cleaned it out this morning before starting. Took everything out and vacuumed out the ash and added fresh lump to it. I use a half of a lightning nugget to get it started and I made sure that the flame was out before closing it up. However I can't tell if it maybe flared back up after closing it. The rain theory sounds like it could be an option as I currently do not have a cover for the egg and it is exposed to the elements.

GrillSgt

There are a lot of ways to get to your target temp but here's mine and I've never been disappointed. I light using a couple of oil soaked folded paper towels and I immediately close the egg up with whatever goes in. Platesetter, drip pan, raised grill. Bottom vent about 1/3 open and daisy about 1/2. When I get to 200 I start closing up the vents to the openings I know will be where the cook needs to be. Bottom vent first and daisy slowly getting to the right opening. Takes about 1/2 hour, 45 minutes top. Your temp needs to be stable for 10-15 minutes before your good.