Checked out the dimensions page, thanks. And, I didn't realize the cast iron collar was removable -- now if the Buck model 74 has that too, it might just work for us.
The house was built in 1966, and the fireplace is built-in, masonry. Has steel block plate, with what appears to be cast iron damper with heavy chain opener, and lined with tightly fitting (mortared) firebrick. Opening is same width and height in back as in front; width is 33.5", depth 30", the height, as mentioned earlier, is probably the limiting factor, at 21.75". It has a raised hearth (limestone slab), which I actually lowered by one course of brick last year, to put it about even with the floor of the firebox (just 1/4" lip at this point). The floor of the firebox (and the hearth again) could be removed and lowered, but I'd really rather avoid that if possible. The chimney is 12" x 12" ceramic tile, I believe; approximately 20'. We had it inspected last year, and they found a crack or small opening (but didn't confirm how far this might extend), so we've been avoiding using that fireplace, until we could decide whether to reline it for use as a fireplace, reline it with 8" (to use an older insert given to us), or reline with 6" (giving us more options with newer inserts). We're leaning towards the newer insert route, as we prefer the cleaner/larger glass viewing window with possible airwash, and the secondary burn for lower emissions and creosote buildup.
I should also mention there is a second fireplace in this house. For time being, we plan to keep that one as a normal fireplace -- it looks very nice and we enjoy the fires in it, albeit it goes through wood really fast. Moreover, our floor plan is not open, but quad level. Given these factors, I think rather than aiming to heat the whole house with this one insert, we'd be happy to heat most or all of the first floor, perhaps down the line a second insert in family room would take care of the upstairs...
One thing I've noticed with inserts in general they tend to be more square in their fireplace opening requirements -- or in other words, our fireplaces both seem generously large in width and depth, but perhaps a tad shorter in height than is/was common. It'd be great if we could find an insert which used more of the width and depth, but with a shorter height of 20-21". With most inserts we'd end up with lots of airspace in back, and/or the sides. Wonder if there'd be much benefit to filling in that space with brick/firebrick, as extra heat mass...
At this point, we'll probably have a local installer out to take a look.
