Any heat benefit to steel doors on standard fireplace?

[jwwill0]

The home we recently moved into has a 2 sided fireplace with heavy steel doors on both sides. They seem to be about 3/4" thick and seal fairly well. There is no alternate outside air intake that I can find. Is there any purpose for these types of doors from a heat supply standpoint, or is it purely decorative? Could you even maintain a fire with all the doors closed?
We are looking to replace these and put a free standing stove in the fireplace next year.

 

[brad wilton]

I might be wrong usually am but i think it's to keep heat in house from going up chimney when not in use

 

[webby3650]

I would guess that the doors were added to prevent smoke spillage. Most all see through fireplaces smoke out if both sides are left open, they aren't supposed to but they usually do.

These doors were added so that they could use either side they choose. Glass doors can't be closed with a fire going because the tempered glass will break. Except for very high end doors, some of those have ceramic glass as an option.

 

[jwwill0]

Great. Thanks everyone. Makes sense.

 

[brad wilton]

Told ya lol

 

[webby3650]

I'm sure it was also to prevent conditioned air from pouring up the flue.

 

[brad wilton]

Thanx almost had it