Heritage side loading door

[nortcan]

I changed the rope gasket on the side door for my Heritage 8024 T.Hybrid. I put a new1/2 inc. gasket as said in the tech. sheet. But the door was almost impossible to be closed , I had to use an unusual force to be able to lock it and that after adjusting the latch as loose as I could. I removed the 1/2 gasket replaced it with a 3/8 new but the door was as hard to close as with the 1/2. I went to the Hearthstone dealer and got an other 3/8 but black, the dealer told me that one would be softer than the other ones. Same thing with the black one , just a little less hard to close the door but still a lot too hard, impossible for my wife to even try it. I changed a lot of seals on different stoves and never got any problem. I changed the seal on the front door of this stove and had no problem. Now, having no good result with the black 3/8, I decided a very curious thing : use a 1/4 rope gasket. So I removed the 3/8 and installed the 1/4 one. The door is easy to close and the latch works correctly. So, having try blak and white gaskets, 1/2, 3/8 and now 1/4 size, what could be the problem? Before and after changing the gaskets I tried many latch adjusments but without good result. Someone know the secret to my problem ?