Here is a copy of page 10 from the quad 2700I insert manual. you can find and read the entire seciton here.
2700 I
The following modifications of factory built fireplaces are permissible: 1) removal of damper; 2) removal of smoke shelf or baffle; 3 ) removal of ember catches; 4) removal of fire grate; 5) removal of viewing screen/curtain; and, 6) removal of doors.
NOTE: Installation into fireplaces without a permit will void the listing.
The factory built chimney must be listed per UL 127 and meet the type HT requirements of UL 103 . Factory built fireplace chimneys tested to UL 127-1998, may be at the fireplace manufacturer’s option, tested to the same criteria as UL 103 HT requirements. If the chimney is not listed as meeting HT requirements, or if the factory built fireplace was tested prior to 1998, a full height listed chimney liner must be installed from the appliance flue collar to the chimney top. The liner must meet type HT requirements (2100ºF) per UL 1777. The liner must be securely attached to the insert flue collar and the chimney top. To prevent room air passage to the chimney cavity of the fireplace seal the damper area around the chimney liner with high temperature sealant.
The fireplace must not be altered, except that the damper may be removed to accommodate a direct-connect starter pipe or chimney liner, and external trim pieces which do not affect the operation of the fireplace may be removed providing they can be stored on or within the fireplace for reassembly if the insert is removed. The permanent metal warning label provided must be attached to the back of the fireplace, with screws or nails, stating that the fireplace may have been altered to accommodate the insert, and must be returned to original condition for use as a conventional fireplace.
If the hearth extension is lower than the fireplace opening, the portion of the insert extending onto the hearth must be supported.
Manufacturer designed adjustable support kit can be ordered from your dealer. See page 15.
Final approval of this installation type is contingent upon the authority having jurisdiction.
Direct Connect Seal OptionFull Listed Liner OptionMasonry ChimneyFlue Tile MantelDamper AreaSEAL DAMPER AREA
Figure 10.1 - Installation Into A Factory Built Zero-Clearance Fireplace
The Quadra-Fire 2700-I Insert is listed to UL Standards for Safety 127 and approved for installation and use in factory built zero clearance fireplaces conforming to the following specifications