Replace fire bricks in fireplace

Question

I have a masonry fireplace where about 8 fire bricks have fallen off of the back wall of the firebox. The fireplace was built in the late 1960's, then mostly unused for decades. I was told that the last time it was used was around 2005. The room was un-climate controlled for long periods and could have had lots of moisture exposure, but is in Texas so unlikely to have experienced freeze spalling.

The bricks do not appear to be keyed in any way, just mortared in with mortar that failed.

Can I remove all of the loose fire brick, then reinstall them with a proper refractory mortar, or is there something different that should be done? Do I mortar the fire brick only to fire brick, or also to the regular brick wall behind it?

Answer 1

If the firebox looks like that the inside of the chimney probably looks worse. This is not a DIY job you need to have a pro run a chimney inspection camera down the chimney or your risking a chimney fire. If you are feeling that lucky then buy a lottery ticket and your winnings will pay for the chimney guy. ;-)