BGE slowly loses temp during long cooks

lkmunoz80

Hello, need some help from the BGE experts.  We've had our large BGE for about six months, and we're quite happy with the quality of food we're creating!  But we have a problem that we can't seem to dig up an answer on. 

No matter what temp we cook at (we generally use the 225 to 300), slowly throughout the day the temp of the dome drops.  We have to bump the vent open slightly more and more every 45-60 minutes throughout the day to maintain the temp.  Once we hit about the six-hour mark of any cook, regardless of meat, the temp starts dropping off fairly drastically. 

Once we get our fire going, we close the daisy wheel to less than 1/4" and roughly the same on the vent.  We hold steady at whatever temp we're targeting for about two hours.  But then over the course of the next 4-6 hours, we'll get to where we have the daisy wheel open 3/4" or greater and the vent at the bottom open the same to maintain our targeted temp.  

This doesn't seem right.  We keep reading that we should be able to set those vents and the fire will hold reasonably steady for hours on end, but this has not been our experience.  Any ideas what we're doing wrong?

PS - I should add, we're starting with a completely clean egg every time.  We empty all of the ash and completely clear the bottom before every fire.

lkapigian

Welcome and quick question, are you running out of file and temp or just temp loss? If plenty if fuel and just temp loss i would assume airflow since you already have 2 of the 3 things needed for fire 

JohnInCarolina

If you have enough fuel (lump) then the only thing that really impacts the temp in the Egg is airflow.  For what you describe to happen, there would have to be something going on internally to your BGE that would be restricting the airflow.  I just have a hard time imagining what that could be if you’re also starting with a clean Egg every time (by the way - there is no real need to do that).  

Could also be something wrong with the thermometer I suppose.  

lkmunoz80

lkapigian said:

Welcome and quick question, are you running out of file and temp or just temp loss? If plenty if fuel and just temp loss i would assume airflow since you already have 2 of the 3 things needed for fire 

We're just running out of temp.  We look down in the pit and the coals are all nice and evenly glowing.  It's just that the temp drops off and we have to continually increase the airflow to maintain a steady temp.  

lousubcap

Welcome aboard and enjoy the journey.  Independent of the aboce issue, above all have fun.
Gotta admit that your described issue and set-up don't make sense.  You have the fuel, fire and air-flow.  No way with those that you should lose temp however, your description independent of anything else reads like a loss of fuel (aka fire source).  So how full do you fill the BGE before each cook?  
You can have glowing lump but if not much of it left then you will lose temperature.  
Make sure your thermo is calibrated although even if not then the relative behavior you describe still doesn't fit for me.
Best of luck.  

lkmunoz80

lousubcap said:

 So how full do you fill the BGE before each cook?  

It’s weird for sure.  We’re filling the charcoal almost all of the way full, but not heaping over the top to start with.  Like level or just under with the top of the basket.  We smoked yesterday for six hours (until our temp dropped off drastically) and now it’s about a third full.

lkapigian

Dumb question but, is the firebox lined up with the opening ....and a long shot, are you extreme elevation 

iudex

Could you provide a picture of the filled egg before lighting?

I am by no means a veteran in the BGE game, but my fire has only died twice on me in over a 100 cooks and only when aiming at 80C and 100C for an extended period of time.

I have never had any significant temp drops for no reason. It should actually bounce back to the set temp even  when adding cold gear or food to the egg (although slowly).

Langner91

lkmunoz80 said:

lousubcap said:

 So how full do you fill the BGE before each cook?  

It’s weird for sure.  We’re filling the charcoal almost all of the way full, but not heaping over the top to start with.  Like level or just under with the top of the basket.  We smoked yesterday for six hours (until our temp dropped off drastically) and now it’s about a third full.

You are only filling the basket?  Like Kick Ash Basket?  You should fill all the way to the top of the fire ring.  You will be way overfilling the basket, but that's ok.  You are running out of fuel.

Fill 'er up!  You can snuff it out after your cook and re-use it.  Charcoal is also the cheapest ingredient in your long cook, so go ahead and put as much in as you can.

lkmunoz80

Langner91 said:

lkmunoz80 said:

lousubcap said:

 So how full do you fill the BGE before each cook?  

It’s weird for sure.  We’re filling the charcoal almost all of the way full, but not heaping over the top to start with.  Like level or just under with the top of the basket.  We smoked yesterday for six hours (until our temp dropped off drastically) and now it’s about a third full.

You are only filling the basket?  Like Kick Ash Basket?  You should fill all the way to the top of the fire ring.  You will be way overfilling the basket, but that's ok.  You are running out of fuel.

Fill 'er up!  You can snuff it out after your cook and re-use it.  Charcoal is also the cheapest ingredient in your long cook, so go ahead and put as much in as you can.

Yes, just filling the kick ash basket.  I bet this this the problem!  We didn’t think to overfill it.  But it makes sense.

We’ll give this a shot next weekend.  Thank you all for the help!

lkmunoz80

iudex said:

Could you provide a picture of the filled egg before lighting?

I am by no means a veteran in the BGE game, but my fire has only died twice on me in over a 100 cooks and only when aiming at 80C and 100C for an extended period of time.

I have never had any significant temp drops for no reason. It should actually bounce back to the set temp even  when adding cold gear or food to the egg (although slowly).

From reading some of these other responses, I don’t think we’ve been putting in enough charcoal.  We’ll trying loading it up next Saturday.  If that ends up not working, I’ll post some pics to help troubleshoot further.

Thank you!!

GregW

lkmunoz80  What you are describing, having to open the vent as the cook progresses, is why I bought a BBG Guru and then a Stoker to automatically tend the fire. There are a number of devices on the market now that utilize a fan to control the temp. There is also one that modulates the damper rather than using a fan.

These temp control units are pricey, some more than others, but you have to ask yourself, what's a night of uninterrupted sleep worth, multiplied by the years of use. It's a pretty good investment.

There are a number of members that use the various brands of temp control devices on the forum. I'm sure they can make a recommendation. 

A temp control is not absolutely necessary, and a true master of the BGE can run the egg all night without babysitting the fire, but I never attained that level of expertise.

dstearn

Looks like you solved your issue. Not enough lump to start. For a low and slow you need to add lump above the basket for longer cooks.

Powak

Yup fill that sucker up to maybe half inch or so below top of fire ring - just enough to fit some some wood between the coal and plate setter. I’ve gone 22 hours on a smoke without workin the vents.

Archcam

You could also check your gaskets to make sure you're getting a good seal when the lid is down.

BigreenGreg

Archcam said:

You could also check your gaskets to make sure you're getting a good seal when the lid is down.

Think this would cause temp to rise, not fall

saluki2007

Sounds like you have your answer but would also add make sure you get an even fire across the top to avoid a straight burn down the middle.