Hi300 back draft/gasket problem?

[rick clifford]

I have had the hi300 for a couple years and never seem to get the heat out of it the way I anticipated and due to a back injury a havent installed the block off plate but it heats the 1st floor ok. Never does it get really warm. (T shirt warm) Thats another story for another day....Well yesterday was my second burn of the season which I didnt want to do as it was going to be about 60 degrees out but my wife was having her sisters over and I was getting out of here. So the temp is 55 and really windy as a Low was moving in and a hugh storm was brewing for later that day. I lit it up as I always do and immediately got a huge back draft and the house began to fill with smoke. Opened front and back doors of the house and partially closed insert door and no good. Couldnt stop the smoke no matter what I tried so i finally shut the insert door completely. HERE it got freaky.. Smoke started appearing everywhere like a Si Fi movie.. Passing through all gaskets and creeping along the living room floor filling the room. Around the door, around the glass with the decorative front almost like it was passing through the glass, sides and bottom of the fan housing. Every where it was appearing. Really wild to see. Now I had replaced my door gasket last year and the section on the bottom of the door has flattened more than the rest and I am going to order another and adjust the latch washers when I do but.. Has anyone experienced something like this and is it common for the glass gasket to wear out too as I now assume that must be shot? Is that hard to replace and how can I tell ifs its shot? BTW my wood is very dry hardwood some going back to super storm Sandy. Finally does anyone know where to get these other than Hampton Regency as their prices are crazy and are there any tutorials for replacement of these gaskets so I do it right.
OK, While I am at it, my chimney is an exterior wall chimney and I am wondering if there is anything non flammable (Pliable blanket like material ) that I may be able to slide behind the insert to insulate back there. Sorry for the blah blah blah and thanks for any tips..

 

[jetsam]

You shouldn't be going through a gasket a year unless it's improperly installed.

Your draft reverse probably had several contributing factors including weather. Others may have been short stack height and envelope depressurization (were you also running a dryer and/or exhaust fans?). Check for flue blockages asap. Get this one figured out- it is a CO hazard even if you are not getting smoke in the house. Look into an outside air kit, especially if it is a tight house. Look into adding some flue if the flue is short.

You can put Roxul (which I think had the name changed to Stone Wool or something last year) behind your insert. They make a product called Safe'N'Sound which is what most people use. If you are concerned that stone wool fibers will somehow get in the house, you can put it behind cement board.

 

[rick clifford]

Thank you. My chimney is 20 feet or a little over. Good point about the exhaust. They may have been in the shower and dryer could very well have been running. I am not sure but will remember that next time. Flue is clean as I had it cleaned before my my 1st fire and visually looked through it. My house is a small cape cod, 70 years old and certainly not tight as when i pull down some dry wall there is very little, thin insulation that has collapsed like an accordian. Oil was cheap back then. Can the roxul rest against the back of the stove. There is very little clearance at the top rear. 1 to 2 inches max. Same for cement board, can that come in contact with the stove? It was weird as I rarely ever get any smoke in the house even during a reload. Thanks again

 

[jetsam]

Yes, stone wool and cement board are noncombustible.

If the house is not at all tight it is a lot harder to depressurize it... but a wood stove, a dryer, a bath fan, and a range hood all going at once is a lot of air being pushed out, too.

I wouldn't count on that having been a one time thing. The least you should do is to put a dedicated CO detector near the stove so you can get notified of any future draft reversals that happen when the fire is low.