That's a little out of my normal service area, but WTH, If you pay travel time, I'm there !!! LOL, I'm sure someone can point you in the right direction.
Nice.... have you ever been in St Louis in the Summertime? Can you spell hot and muggy!
I have a lead on a fireplace company not to far from here as the ones who sold it to me more or less said that they can't figure it out.
Par for the course I guess!
A question to everyone what is a good brand? Obviously this "heat n glo.... Royal brand" is one i am going to avoid at all costs in the future. I hate buying stuff twice when it should work the first time.
From an analytical point of view, this is what I think is happening. When you have a fire in the Fire box, the box and the door expand due to the heat. There is an imperfection in the casting with the way the box and door fit together. When the unit is heating up the expansion provides enough clearance for the door to slide over this imperfection. When you cool down the contracted parts get smaller and there is not enough clearance for the parts to slide back over this imperfection. The tension slowly builds up till it's past the resistance point. Then you get this sudden release of energy, as the door goes back in to place, and the glass breaks do to the shockwave. BiMetal Klixon switches use this same action, I've had my thumb busted open from the metal going back in place.
Could you get a piece of heavy gauge sheet metal and have it cut to the dimensions of the glass? Install it temporarily in place of the glass. Mark where the door is. Heat the unit up, and see where the door is. It should be close to the cold mark. Cool the unit off and check several times over the next hour for uneveness on the match up of the mark? IE it's an 1/8" off on one corner and 3/8" off on the opposite corner.