AS owners: low roar in stove pipe?

For testing MC of splits....I wonder how long it takes the piece of wood to get to that 70 degree mark for testing? It's supposed to be almost 70 here on Friday... If I test in the afternoon near the high temp of the day, is that sufficient...or do I need to bring a piece of wood into the house (temps 68 ish degrees) for "x" amount of time to let the wood warm, and then test? Not trying to overly complicate things, but I imagine those details do matter if you really want to figure things out....

 

Here's what I'm thinking-
I was on the lookout for the sound myself today when I got home from work and got the fire going. The sound I'm used to as I described in a previous post about the whoosh/rumble combo gets going on mine when the stove starts to really heat up and get going.
What I think is happening is as the stove is reaching temperature, the wood begins off gassing more- and the hybrid design of the stove has the secondary burn working in conjunction with the catalytic burn. I don't have a technical grasp on what's happening or the vocabulary to describe it, but what I think is happening is the air is being shot in through the secondary supply and it's becoming really productive and that's the sound you're hearing.
Check out the diagram of your stove below- I think you're hearing a rush of the air/gasses being combusted.

 

I know downdraft boilers have a certain "rumble" when they are gassifying...little different animal though...

 

Should read dryer when warmer...

Correct, its just that the meter is calibrated for a certain temp (the cheap ones we all use for firewood are supposedly at around 70*F, the moisture in the wood is the same no matter the temp.

 

Try measuring some splits outdoors Fri. afternoon. If you can, also take a few splits indoors for 24 hrs and test them afterwards for a comparison. Good test. Your meter may also have a temp option if its like mine. Fun toy.

 

I'll have to look at mine to see if it has a temp option. Really haven't looked too much into it to see what, if any, options it has.....

 

I found a post from another wood forum from about 10 years ago where a couple of people chimed in mentioning they have the same noise coming from their catalyst.

You've got the essentials covered from your earlier posts: stove pipe cleaned / chimney cleaned / stove maintenance / dry wood.
See if playing with the air control gives you a better peace of mind.

 

Not sure if you are asking me for the make/model M/C meter I use? Fleabay China special. Likely straight from Wuhan The entire investment was $10 to $15 including shipping. This model is not exactly the same but similar.

Digital LCD Wood Moisture Meter Detector Tester Wood Firewood Paper Cardboard | eBay

 

Yes that was what I was asking but I think I screwed up my post. Thanks!

 

Thought you might be interested in our tentative results:
After many emails, 20-odd pictures, a handful of phone calls, and some welding, the noise has been determined to be: unknown.
The most interesting possibility we checked off the list was the tertiary air intake on the back of the stove. They have a little pad that sometimes slips off after years of wear. Alas, this wasn't our problem. But, all in all, I did get to know my stove a little better and accidentally fixed an issue with the damper.
The noise hasn't happened again. I think 4 times in total? Our weather has been unseasonably warm, so we had some time without any burning, and I am significantly less uptight about the whole thing. Woodstock is still mulling this issue over and if it does happen again, I'll be trying to record the noise so they can hear it second-hand, at least. For now, they don't think it's a hazard, as the stove still seems to be operating well and there isn't any obvious damage occurring anywhere.

Per the hypothesis from RGrant about the stove being really productive-- I did mention it in one of my phone calls with Woodstock. They seemed to think it was "possible, but not common" enough for them to confirm that's what's going on with my stove.

Thanks for the help everyone. If I ever have a proof-positive answer on this noise I'll make sure to update this thread.

 

Its a feature, not a defect.

 

Over the last couple years I've occasionally (maybe 6 times) had a very brief small rumble like explosion. Needless to say, it was very concerning, I checked my stove and pipe, the connections, and all looked good. I cleaned my pipe and got a little more than a cup brown ash, of coffee consistency. After some research it seems like the most likely reason was a back puff, but it didn't seem to fit all I read about back puffs. I still don't have a definitive answer, and that drives me crazy because I want a solid reason. It happened a couple weeks ago, and I've come to live with it.