Is this wood insert safe to use?

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New Member
Feb 1, 2023
Hello! I recently purchased a home that came with a Blaze King Princess 29 insert. Upon further investigation, it looks like the original fireplace was a Vermont Castings Winterwarm Zero Clearance insert with energy box. It looks like the previous owner replaced the insert with the Blaze King unit. From my research on the Winterwarm it looks like only the Winterwarm system was designed only for the Winterwarm insert. However, I was able to use an inspection camera to look around and the energy box is surrounded by concrete blocks, not combustible materials like the typical installation. The only combustible materials touching the concrete blocks are 1/2" furring strips on the front facing of the fireplace that the drywall is attached to. The closest furring strip is 16" above the insert which exceeds the clearance to combustible facing listed in the manual for the Princess by 2". There is also a heat shield with air gap between the furring strip and top of the fireplace. We have a masonry chimney with a 8" SS insulated liner with reducer to 6" single wall stove pipe that is attached to the insert.
Is this wood insert safe to use?
The blaze king manual states it is only allowed to be installed in a code compliant masonry fireplace. I’m no familiar worth the winter warm ZC. The professionals @bholler and @begreen can offer better advice
Because the box is inside block it may be ok. But honestly there is no way for us to know without being on-site for a full inspection
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It may be safe to use but it won't pass code so if something bad happens you won't be covered by insurance.
BKVP...It's not just about clearances. Your insert is very heavy. Few factory fireplaces are structurally engineered for 350lbs.

If it shifts or settles and the liner is compromised.....

Thank you everyone for the feedback. Sounds like I’ll need to find a pro to do a thorough inspection to back up my observations.

@BKVP the original Winterwarm insert that was installed there was actually 475 lbs. so we should be good there!