I have the same stove as you with the 3 glass panes. Mine was refurbished at the Harman factory and new glass was installed at the time. The gaskets were installed as you describe and I have had no problems what so ever. I have been burning this stove for 17+ years now.
Which way are your gaskets again? I've talked about so many ways I'm not sure which your referring to! LOL
To experiment, I installed the gaskets leaving only the bottom open and fired it up. It burns quite fine, but I can see how the air wash would work much better with the top open as well. It seems to me that's the way it was designed as many of you have pointed out. I plan on removing the gasket from the top of the panes as well..... thanks for all the input!
The stove was in the house when I bought it 1.5 years ago. The only thing the previous owner burned was a substance that resembled oregano.... needless to say, a set of gaskets and cleaning was all that stove needed to be the primary heatsource despite the previous owner saying it didn't burn well.
As for getting parts, I went to a dealer local to where I live in Glen Rock which is in York County. What a mistake! I'm very familiar with the folks at Fisher Stoves as I'm from the Tunkhannock area. My Grandfather always burned Fishers. From now on my parts will be picked up on my trips home!