Hearthstone Montgomery WFP-100 Door Gasket Kit
REPLACING THE DOOR GASKETS: It is important to maintain the gaskets in good condition. After a year or more of use, the doors gaskets will compress and become hard, which may allow air to leak past it. You can test the condition of the door gaskets by closing and latching the doors on a strip of paper. Test all around the door. If the paper slips out easily anywhere, it is time to replace the gasket.
Place the door face-down on something soft like a cushion of rags or piece of carpet. Remove the old gaskets from the door by pulling and prying it out with an old screw driver. Then use the screwdriver to scrape the old gasket adhesive from the door. Now run a 1/4" (6 mm) bead of high temperature silicone in the door gasket groove. Starting from the middle of the hinge side, press the gasket into the groove. Do not stretch the gasket as you place it. Leave the gasket about 1/2" long when you cut it and press the end into the groove. Tuck any loose fibres under the gasket and into the silicone. Close the door and do not use the fireplace for 24 hours.