I have an insert fireplace that is on a raised platform. I want to lower it to normal height (i.e. almost level with the floor). I am looking at the setup and I am not sure how to (non-destructively) disassemble it. The problematic part is disconnecting the flue and what appears to be a firewall around the flue. (By flue I mean the tube leaving the firebox where the smoke comes out, to be clear.)
In each picture the number points to the same feature, with an 'a', 'b', or 'c' modifier in later pictures to make it easier to refer to which picture you mean.
1 is the outer "firewall" around the actual flue.
2 is what I'm calling the "flue"--it's the pipe where the smoke travels out.
3 is the top of the firebox.
4 is what looks like a standard sheet metal screw to me.
5 is an indentation I don't know the purpose of, possibly irrelevant.
Annoyingly, I did not mark the screws that hold part (1) to part (3)--two of them are very clearly visible and close together in the foreground of the (a) picture.
So, if I unscrewed those (the unmarked screws), I think that part (1) would be free from the lower assembly and able to hang in place. (1) is strapped to the frame of the house as you can see in the (b) picture (although it looks like stabilization, not really weight bearing, maybe?).
Supposing I had those (unmarked screws) unscrewed, how do I get the firebox down? I can't see under part (1) so I don't know how the firebox connects to (2), the "inner" flue/exhaust pipe. Does that pipe just go a short distance up or is it all the way up the chimney? I was assuming it went all the way up the chimney, but was in segments like (2) is. I don't want to damage that pipe but I'm not sure how to safely disconnect it.
My end goal is to disconnect, then get a short length of (1) and (2) to extend the flue downward to where the firebox will sit in the final installation.
(Also, please feel free to correct me on terminology; I will edit and fix so it's easier for people to understand/find the question.)
Top of the firebox:
Closeup of same:
Outer firewall/separator:
Upper piping:
