Central Boiler E-Classic 2400 rear doors blown off!

[DeerMeadowFarm]

Saturday night it started getting cold in the house. Sunday morning I went outside and sure enough the fire was out in the boiler, BUT the wood was still in it unburned. I got it going again but then I closed the bypass lever the temp started dropping. When I opened the door, it would take off again. This has happened in the past when my intake tube has gotten packed with creosote but since I added my removable side plates inside the boiler box, I haven't had hardly any backup but I went to check.

To my surprise, both access doors were lying on the ground, side by side, just as if they'd fallen together off the back of the boiler. This was strange... I checked the intake tube and it was clean, but the solenoid wasn't opening the cover. Of course I don't keep a spare solenoid, so I propped it open so it would allow air into the firebox.

I was in the middle of evaporating maple sap so I'd mess with the OWB and then check on the evaporator. Each time I'd come back, the OWB was on the verge of going out. WTH? So I ran it for a while with the bypass lever open for a while. When I came back to check it again the temp was getting there, so I closed the bypass lever. When I did, smoke started coming out from under the roof and out of the back panels, like a lot! Then, right in front of me, both rear doors blew right off of the back of the OWB!!!! Obviously it must have happened before when it went out because the panels were lying there just like I found in the morning. What would possibly cause this????

I opened the bypass and ran the OWB with the door open for 5-10 minutes while I checked back on my evaporator. I came back to the OWB, closed the door, closed the bypass, and it ran fine the rest of the day and all last night!

I don't know who to talk to as just this Friday we received a letter in the mail saying the place we purchased our OWB from was no longer a Central Boiler dealer and to go on line to find another one.

[E Yoder]

Sounds like a clog somewhere, with a small wood gas explosion that can't get out the chimney.

[buckgrunt]

I have a CB-2300 and I cannot fathom why the "rear doors" would blow off.  Photos would be nice.  I have had flashes of flame shoot out of my firebox before when I open the firebox door, but never something like this.  The only explanation is that your fire was Oxygen starved and somehow when some Oxygen entered, the rear doors blew off.  Like Mr Yoder stated, there must be a clog somewhere that did not allow Oxygen to enter the firebox.  Check your chimney, by-pass door, air channels and air holes...

[DeerMeadowFarm]

I can't fathom it either that's why I was asking about it. How would smoke escape from under the roof and rear doors? I mean, there was a lot of smoke before the doors blew off!

[bobby s]

I'd check to make sure the reaction chamber isn't blocked with ash/coals.
Are you getting good exhaust  flow up through the heat exchangers and out the chimney?

[DeerMeadowFarm]

It seems like I get good flow. The chimney bellows smoke...?

[Roger2561]

Have you removed the outer skin of the OWB to inspect everything?  And have you removed the end cap off the chimney Tee to see if there may be a restriction/clog in the horizontal piece?  I've experienced minor "explosions" on my E-Classic 1400 but nothing like you are describing; mine was more of a "poof".

[DeerMeadowFarm]

All I've removed are the back doors and inspected the "T" in the chimney, which was clear except for a little fly ash. I've never taken the sheet metal off of the sides or anything before...?