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Fireplace Glass Blowing out

I have a Monessen 320DV4136NV (without blower) natural gas fireplace that was installed while my house was being built in 2001. The glass has blown out of it 3 times (the last time being last night). We are empty nesters so there is not activity in ther home that would scratch or damage the glass. There has not been any cleaners containing any abrasives which could scratch the glass. The 1st time Monessen replaced the entire door. The second and third replacements were done by different fireplace dealerships. The last replacement was not even a year ago, The glass didn't even have a chance to get dirty! No one (includung Monessen can tell me why this is happening. The door does have the optional brass door trim from Monessen. CAN ANYONE HELP ME! Outside of the shear expense, it's dangerious to have bits of glass being expelled into our living room.

Frustrated by watching TV in goggles
Dean C. Sippel
[email protected]

Re: Fireplace Glass Blowing out

Just a suspicion, but your gas fire may be to close to the glass and it is not heating evenly. If you hold a flame on one spot on a pane of glass it will explode due to the localized heat expansion.

Re: Fireplace Glass Blowing out

1) Tempered glass is only good to about 600-700 degrees. Ceramic glass will get you to 800-900 degrees. But, it's very easy to exceed these temperatures in most fireplaces. Get a non-contact infrared thermometer and see what temperature it's burning at.

2) What does the manufacture say about the doors being open/closed when burning a fire?

Blue RidgeParkway
Re: Fireplace Glass Blowing out

any chance someone squirts or splashes water on the hot glass doors, even fido or felix walks by and sneezes on them, then glass breaks?

or does this happen just as your starting up? if so i'll guess that between uses you're getting condensation on the inside of the glass doors and frame and that these doors explode soon after you've started a fire and closed the doors up after a period of time which the fireplace was not in use and the insert, gas logs flue are very cool and full of condensation. therefore creating cool spots on the glass when the rest is heating up much quicker is this direct vent fireplace on an outside cold wall and has a radiant heat plate?

is your vent clogged? gas logs not in the proper arrangement?

is somebody putting anything foreign in the fireplace like those scent cones, scented paper, etc. - anything foreign can burn too hot enough to burst the doors in a DV even a bunch of dust bunnies and cob webs.

the other guess is that you're running it too long without a blower on and everything is shifting and pinching putting too much pressure on the door frame breaking the tightly sealed glass. is the convection air intake blocked by furniture or full of dust or dog hair in the grille? something blocking the convective heat coming out of the top front? why don't you have a blower for the direct vent fireplace? fan broke or never opted for it? I'd get one especially since your blowing doors. if you have a radiant plate you'd then have to remove it. you don't have a natural (b)vent log set in a direct vent fireplace do you?

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