Amerique heating incident - Please help!!

The canola spray does contain a propellant of isobutane and propane, but their ignition pt is well above 400 F. There is a dimethyl Silicone additive as well, but it should be stable at the the temp of the incident. The string is 100% cotton.

Any thoughts?? 1 hour later, things look normal. Temp gage and internal temp are equal.

If you search for post: BOOM/BANG  it may give you some kind of idea.  I've had it happen just a couple of times and have heard of it before with friends of mine.  Seems mostly to be from using too much wood creating a lot of smoke.  Never seems to hurt the smoker.

It does usually get your attention when it happens!

 Yes, it can be a little exciting. I've seen it too, and I've thought it might be due to moisture in the wood, or perhaps the wood briefly igniting instead of smoldering. I never have figured it out but it doesn't seem to cause any bad result, and hasn't recurred in the past year or so.

Cookshack says that there are several variables, in my case most probably too much wood smoke at the onset of the cook. At some point, it goes pressure critical, releasing through door and vent, then creates a momentary vacuum before going back to normal. Tech OPS says it's not really an issue, but he heard of incidents on larger commercial models where the "burp" is so powerful that the smoker doors are damaged.

Having never experienced this before, it definitely caught my attention at a distance of 5 feet. I'm glad I wasn't drinking or I might have wondered if this event happened at all.