What is this metal grille for?

[Scarlet Raven]

My home is built in the 1920s, and I have done all sorts of online searches to find what this is called and how it functions, but I've come up with nothing. I apologize for misidentifying any parts of the fireplace...

On the front of my fireplace, above the brick surrounding the fire area, below the wooden mantle shelf, there is a metal grate. Behind it lies 3 large open tubes. We've assumed it is a venting mechanism for hot air. The only reason I'm asking now is because I'm remodeling and I want to make sure when I redo this area, it keeps true to the original design. I have no idea how it works, so I'm hoping someone here can enlighten me.

Thank you in advance!

 

[begreen]

Sounds like the fireplace has a heat exchanger built in. Hot air exits out of the grille. It might be a heatform style. Is the firebox metal or masonry?

 

[Scarlet Raven]

Sounds like the fireplace has a heat exchanger built in. Hot air exits out of the grille. It might be a heatform style. Is the firebox metal or masonry?

It seems to be metal. I just looked up "heatform fireplace" and it does have those cool air inlets on the sides also. Thank you.

 

[begreen]

It seems to be metal. I just looked up "heatform fireplace" and it does have those cool air inlets on the sides also. Thank you.

Yes, most likely it's a heatform then.