Smoke explosions...

[benson56]

So I put some chicken in the smoker and set it at 250*. When the pellets get hot enough to ignite, there's a small explosion and smoke puffs out of the smoker somewhat violently. What the heck is causing this and how do I prevent it?

 

[chopsaw]

When the pellets get hot enough to ignite, there's a small explosion

What type of smoker ?
Sounds like it might be an electric . Like an MES . If so DO NOT use pellets on the heating element in an MES .

 

[smokerjim]

If it's a pellet smoker are you starting it right,

 

[DougE]

If it's a pellet smoker are you starting it right,

That's what I was thinking. I've seen quite a few videos of pellet grills going boom from people starting them with the lid closed.

 

[smokerjim]

Yep, my pellet grill I start with lid open on lowest setting until the fan kicks on and clears the heavy smoke, then I close the lid and set it 300 , when it settles in around 300 then i set to my temp, if its lower then 300 I'll open lid for a bit to let some heat out. Your probably seeing the thick smoke when your smoker hits a certain temp and the fan kicks on igniting the pellets.

 

[mosparky]

I learned years ago when I was internet researching about knife making that wood will off-gas very volatile gases when heated. Some folks were making char-wood (much like lump charcoal) for their forges. This is wood baked until fully charred like lump. The baking vessel must be vented due to said off gassing.
I seem to remember a few threads here when I first joined, where people had their MES door blown completely off due to mis-haps of this nature.
You got lucky.
Note : always vent the smoker.

 

[DougE]

My Camp Chef has a startup cycle. With the lid open, select cook temp and smoke level. It will then start. When the startup cycle completes, close the lid and let it come up to temp.

 

[chopsaw]

wood will off-gas very volatile gases when heated.

Exactly . When the mixture leans out enough it explodes .

I seem to remember a few threads here when I first joined, where people had their MES door blown completely off due to mis-haps of this nature.

That's what made me think MES . Can also blow the chip loader out of the hole .
You can do the same thing with loading to many wood chips .

 

[chopsaw]

Yep, my pellet grill I start with lid open on lowest setting until the fan kicks on and clears the heavy smoke

I was wondering about this , because my SmokeFire starts with the lid closed .
I've seen the videos of other grills incorrectly started . Pretty scary .
I questioned that at first , but it says on the display " heating up keep lid closed "
The fan comes on right away at high speed . So maybe that's the difference ?

Just so there is no confusion . Follow your grills start up procedure .

 

[DougE]

Just so there is no confusion . Follow your grills start up procedure

Yep. Mine says to start with the lid open. I get a notification on my phone that says, "Startup is now complete, you may now close the lid", or some such when startup is done.

 

[YoderGuy]

I was wondering about this , because my SmokeFire starts with the lid closed .
I've seen the videos of other grills incorrectly started . Pretty scary .
I questioned that at first , but it says on the display " heating up keep lid closed "
The fan comes on right away at high speed . So maybe that's the difference ?

Just so there is no confusion . Follow your grills start up procedure .

My Yoder is the same as your SmokeFire, fan kicks on as soon as you press the power button, then you hit the ignite button. (start)
Smoke is unburned fuel, the result of incomplete combustion, so if the cabinet is full of thick smoke from a smoldering fire when air is suddenly introduced, you get a Backdraft in a structure fire situation.

A backdraft is a smoke explosion that can occur when additional air is introduced into a smoldering fire and heated gases enter their flammable range and ignite with explosive force. A backdraft is an “air-driven event,”

Hence having " had their MES door blown completely off" makes perfect sense

 

[chopsaw]

you get a Backdraft in a structure fire situation.

Yeah , I'm not using the correct terminology I guess . I understand it though . Been involved in rated enclosures and smoke wall construction .

Good to know on the Yoder .

 

[benson56]

Yes it is a MES. No fan. I've used it alot with pellets and this the first time I've seen it puff like it did. I'll leave the door open until it gets going. Thank you for the help.

 

[chopsaw]

Yes it is a MES.

I figured it was from the way you described it . Man be careful . Don't pile them to deep . Do you have a tube or a tray ?

 

[BrianGSDTexoma]

Hmm first hearing about this. Have a RecTec I guess that would go for that also.

 

[SmokinEdge]

My Yoder is the same as your SmokeFire, fan kicks on as soon as you press the power button, then you hit the ignite button. (start)
Smoke is unburned fuel, the result of incomplete combustion, so if the cabinet is full of thick smoke from a smoldering fire when air is suddenly introduced, you get a Backdraft in a structure fire situation.

A backdraft is a smoke explosion that can occur when additional air is introduced into a smoldering fire and heated gases enter their flammable range and ignite with explosive force. A backdraft is an “air-driven event,”

Hence having " had their MES door blown completely off" makes perfect sense

I run a YS640 they are nice machines. Much different than the GMG I had before. That one would often huff on ignition, for lack of a better word. Like a flash ignition kinda. Yes the Yoder runs the fan continuously, the GMG didn’t and that made sense to me. Once the set temp was reached the fan would surge at low speed just enough to keep the coals hot. As the pit temp lowered the fan would kick back up to steady full speed.

 

[normanaj]

Yes it is a MES. No fan. I've used it alot with pellets and this the first time I've seen it puff like it did. I'll leave the door open until it gets going. Thank you for the help.

Where are you putting the pellets?The MES chip tray IS NOT designed for pellets.

Use an Amazen tray or tube placed properly and you'll not encounter that issue again.

 

[YoderGuy]

Hmm first hearing about this. Have a RecTec I guess that would go for that also.

Sounds like your fan comes on at startup, should be ok with the lid closed.
I watched several videos on the tube and the Recteq guys never left the lid open on startup.
But you should always read the startup procedure in your owners manual to be sure, would not want to blow the horns off that baby.

 

[chef jimmyj]

That's what made me think MES . Can also blow the chip loader out of the hole .
You can do the same thing with loading to many wood chips .

LOL. Been there, did that. First run of my MES I added 1 Cup of Chips, a full load. A few minutes pass and BANG! A flash of fire and my loader gets blown out into the yard 3-4 feet. Scared the heck out of me!

Here are a couple Videos on Exploding Pellet Smokers. The first sounds like a Flame Out and restart without clearing the excess pellets out of the burn pot. The second seems to be a Start up with closed door explosion... JJ

 

[chopsaw]

1 Cup of Chips, a full load. A few minutes pass and BANG! A flash of fire and my loader gets blown out into the yard 3-4 feet

Yup . The first models you could fill the whole length of the loader . They figured out it could be a problem , so they blocked off half of the capacity .