Had a hopper fire last night, need advice

[mgambuzza]

This morning no fire trail, no sawdust trail up the chute - feel much better than the sinking feeling I was having yesterday looking at the flames playing "follow the chute".

 

[goathead]

This morning no fire trail, no sawdust trail up the chute - feel much better than the sinking feeling I was having yesterday looking at the flames playing "follow the chute".

Good news! I had a bad batch of pellets last year that kept clogging the auger with all the sawdust. Glad to hear you got it cleared up.

 

[Czech]

Whether the chute is plugged with pellets or even has saw dust on it, it still needs postive airflow up the chute to burn back. The fire box should be under negative pressure, thus causing a slight draw of air down and out of the chute (hopper is not sealed for this reason?). Try lighting a pile of pellets with a lighter sometime. After you've burned the heck out of your thumb from the lighter, note that there is no way a pile will smolder or light without airflow, even if you do wait until your thumb is blistered and get the pile lit in the first place. The sawdust deal is not a big problem, my stove does this all the time. Basically it tells me I should vacuum out the hopper and auger next time the stove runs dry.

 

[BIGISLANDHIKERS]

Whether the chute is plugged with pellets or even has saw dust on it, it still needs postive airflow up the chute to burn back. The fire box should be under negative pressure, thus causing a slight draw of air down and out of the chute (hopper is not sealed for this reason?). Try lighting a pile of pellets with a lighter sometime. After you've burned the heck out of your thumb from the lighter, note that there is no way a pile will smolder or light without airflow, even if you do wait until your thumb is blistered and get the pile lit in the first place. The sawdust deal is not a big problem, my stove does this all the time. Basically it tells me I should vacuum out the hopper and auger next time the stove runs dry.

The Hopper lid on my Mt Vernon AE has a seal on it. Is it different than the Castile?

 

[Czech]

Yes. The Castiles that I've seen do not have a sealed hopper.

 

[goathead]

Ok, finally got the stove back yesterday. They replaced: Exhaust motor, convection blower, auger motor and assembly, and the door gasket. They also bead blasted everything while they had it apart to clean it. They couldn't give me 100% answer on why, but said it was likely a combination of things that were in bad shape that caused it:

Exhaust motor: Failed - definitely part of it, most likely the initial cause
Door gasket: Frayed and leaking - in retrospect, I probably should have replaced this although I wasn't sure "when" was the time to replace it. Obviously next time as soon as it shows any wear I'm changing it.
Convection blower: Bearings were dry and seized. This had pellets lodged in the fan blades which likely threw it out of balance and burned the bearings. Think this may have been induced by a curious 4 year old and 2 year old firing pellets down the convection tubes. Grrr.

The auger motor cooked as a result of the fire.

So, they ran the stove for 3 days and said it runs perfect. I'll be hooking it back up today and looking forward to shutting the electric heat off. All set with $450/month heating bills. Ugh..

Lessons leaned:

I'll definitely be a better cleaner and will give it a more thorough inspection every year going forward. Taking apart the exhaust blower and convection blower to inspect the fan blades and clean them thoroughly. Also, if the kids are giggling...they are up to something. Thanks for all the tips and advice!

 

[Lousyweather]

I have to hand it to you, Goathead! You seem to communicate in your lessons learned that youre taking at least some of the responsibility...all too rare these days! hats off to you. Also, kids: Weve taken matchbox cars out of augers, and crayons out of heat exchangers....the little buggers can mess with stoves!

 

[stoveguy13]

Dirty stoves can cause some real issues keep it clean you should be happy from now on. cleaner it is the better it will run and heat.

 

[goathead]

I have to hand it to you, Goathead! You seem to communicate in your lessons learned that youre taking at least some of the responsibility...all too rare these days! hats off to you. Also, kids: Weve taken matchbox cars out of augers, and crayons out of heat exchangers....the little buggers can mess with stoves!

I'm just hoping that others learn from the experience that I've had. This is my first pellet stove so even thought it's been five years it's still a learning experience. Some things I took for granted I learned I need to pay more attention to and they aren't as "hands off" as they are sometimes portrayed. If I made a mistake, I made a mistake...fortunately it wasn't costly (other than financially). I know what to watch for going forward and I'm glad I know that now. I also learned the importance of multiple smoke detectors and multiple CO detectors which have been added. I'm extremely thankful that the experience was as it was and not worse and hopefully it will give folks tips on what to check and keep an eye on.

 

[jtp10181]

Sorry if this has been said already but I only read the first post. One of the things that is often overlooked is the holes in the burn pot. If these are not cleared out regularly the stove will appear to "over feed" which actually its juts not burning fast enough due to lack of air to the fuel. I had a customer locally with a Castile (or maybe Santa Fe) have a hopper fire and he insists there is something defective about the stove because he is perfect and has not done anything wrong. He wont pay us to come look at it either so I ordered a new auger assembly (everything that could melt on his, did). Only thing we can think of is that the burn pot holes here not cleaned on his unit.

 

[Jack Morrissey]

Your baffle plate is definitely not in the right position Should be a inch plus gap on the left

 

[Jack Morrissey]

On second thought, that baffle plate is definitely in the wrong place if it was on a 2006 castille insert like mine, i guess yours is an earlier model- Very big difference in the positions!!

 

[goathead]

It's a 2004 model, baffle is in the right place. Left it in place and the dealer verified that.

 

[alexdrozd]

I still don't get why a hopper fire would start. Even if all 3 of these items failed, shouldn't the snap disc sense an overfire and stop the auger from feeding more pellets? No pellets, no fire, correct? Can someone please explain?

 

[JIM P1]

looking at the second picture (assuming nothing was touched prior to the shot) i'd say the exhaust blower failed and the stove fed for a time before it stopped feeding, thats likley where the ash around the chute came from ,the pot would have piled up and fuel would have nowhere to go, combine that with possible negative pressure (does the instert have an oak?) or an at least partially stopped up flue. smoke is pulled or forced up the chute from the lack of exhaust allowing positive pressure to build in the front of the stove, heat and all, cooks the pellets all the way back , usually a sealed feed system and hopper will help to keep this from happening, also the stove should have had a trip switch of some sort that would have killed the auger as soon as the exhaust blower stopped. if this stove is so equipped i'd take a look at that particular sensor as well assuming it didnt trip and stop the auger from continuing to feed.

burnbacks arent common , usually it takes more than one component failing to cause this usually exhaust blower being one ,and its monitoring sensor being the other. pellet stoves are rigorously tested to assure that the design can withstand and contain a hopper fire, usually the only thing getting out of the stove is smoke.

i do not really know how the quads are set up to avoid this so i cant point you to a direct part or sensor, but usually the setup is laid out in their tech manual.

hope this helps ya.

The only thing I touched in that picture is the white mark on the fire brick. I gave it a quick scrape to see how thick the soot was. The quads have a vacuum switch as well which should trip if the exhaust stops so I'm wondering if the vacuum switch failed also? I might bring it up to the place I bought it and have them take a look at it. I have to totally disassemble it to clean it thoroughly anyhow.

For the other poster, The stove is either 4 or 5 years old so unfortunately it's out of warranty.

 

[JIM P1]

HOPPER FIRES ARE VERY RARE. I KNOW THAT IF THE STOVE IS OUT OF WARRANTY MY COMPANY WOULD REPLACE EVERTHING ON THE STOVE THAT HAS CREOSOTE ON. ESPECIALLY THE AUGER IF IT CAN'T BE CLEANED PROPERLY. YOU HAVE TO GET RID OF ANY STICKY OR HARD COATINGS OF CREOSOTE. AT HARMAN STOVES THEY REPLACE THE STOVE IF THERE IS EVER A FIRE WHILE STOVE IS UNDER WARRANTY. THANKFULLY, WE HAVE ONLY HAS TWO IN THE LAST 4 YEARS. WE HAVE SEEN A FEW QUADS WITH HOPPER FIRES. IF THE COMBUSTION BLOWER FAILS THEN THE SMOLDREING FLAMES CAN GO STRAIGHT UP THE PELLET DROP TUBE. IT DOESN'T TAKE LONG FOR CREOSOTE TO MAKE A MESS AND IGNITE. CALL YOUR LOCAL DEALER AND IM SURE THEY CAN HELP.

 

[woodsman23]

HOPPER FIRES ARE VERY RARE. I KNOW THAT IF THE STOVE IS OUT OF WARRANTY MY COMPANY WOULD REPLACE EVERTHING ON THE STOVE THAT HAS CREOSOTE ON. ESPECIALLY THE AUGER IF IT CAN'T BE CLEANED PROPERLY. YOU HAVE TO GET RID OF ANY STICKY OR HARD COATINGS OF CREOSOTE. AT HARMAN STOVES THEY REPLACE THE STOVE IF THERE IS EVER A FIRE WHILE STOVE IS UNDER WARRANTY. THANKFULLY, WE HAVE ONLY HAS TWO IN THE LAST 4 YEARS. WE HAVE SEEN A FEW QUADS WITH HOPPER FIRES. IF THE COMBUSTION BLOWER FAILS THEN THE SMOLDREING FLAMES CAN GO STRAIGHT UP THE PELLET DROP TUBE. IT DOESN'T TAKE LONG FOR CREOSOTE TO MAKE A MESS AND IGNITE. CALL YOUR LOCAL DEALER AND IM SURE THEY CAN HELP.

Most times it is so hard to even get in touch with a dealer but this guy is a dealer and he continues to yell... (welcome)