Sweep's Library: Installing Insert in Manufactured Fireplace

Q: I want to put a fireplace insert in my manufactured zero-clearance fireplace, but my local Chimney Sweep refuses to do the installation, even though the insert in question is UL listed for installation in manufactured fireplaces.  He says he's afraid of liability issues in the event that something goes wrong, because this insert was never tested or listed for installation in this particular fireplace model.

A: You might ask your Sweep if the last insert he istalled in a masonry fireplace was UL listed for installation in that particular fireplace.  Of course it wasn't: it was listed for installation in ANY code-approved masonry fireplace.  This is known as a "blanket listing."

The UL listing that allows installation of a given insert in manufactured fireplaces works the same way, as long as the fireplace manufacturer doesn't specifically forbid inserts. Note: the insert must be installed without modification of the fireplace other than removal of the damper assembly and smoke shield, if present.