Rope Seal for Stoves
Air-controlled appliances must have a way to reduce leaks into the firebox so that the only air entering the stove or firebox is through the air control. There are some older stoves that have fitted ground cast iron "gaskets" that seal well enough without rope seal, but almost all modern wood stoves need gasket material around the loading doors for sealing. Some ash pan doors have such gaskets too.
Gasket material used to be made from asbestos, but now it is made from various densities and sizes of glass fibre. Most rope seal gaskets are from 3mm to 20mm thick. If you need a new rope seal but don't know what size or density to use, you can remove the stove door and take it with you to a stove supply store where you can test a number of rope seal gasket sizes in the groove. In some cases the gasket is cut to length from a reel, and sometimes it comes pre-cut in a kit with the cement you need to hold the rope seal in place.
If Vitcas Heat Resistant Rope Adhesive doesn't come in a kit when you buy rope seal, you can purchase a small tube of it. If you can't find something specifically labeled "Vitcas Heat Resistant Rope Adhesive" you can use silicone sealant that comes in a caulking tube. Users debate whether silicone hardens the gasket sooner or later than stove cement, but there isn't that much of a difference.
Installing the gasket is simple. Remove the door and place it on a sheet of cardboard or an old cloth. Pull off the existing gasket. Next, clean out the gasket groove with a screwdriver to get out any pieces of old silicone or gasket cement. Clean out the groove with steel wool to give the door a clean surface for the cement or silicone to bond to.
Apply a bead of 5mm to 10mm wide (depending on how thick the gasket is) along the entire groove. Then lay the rope seal in the groove being careful to avoid bunching or stretching it. Start on one of the long edges of the groove. When you've gone all the way around, cut the gasket a little longer than you need so that the ends can be tucked into each other and form a continuous seal. Gently press the gasket in place all the way around.
When the cement or silicone is dry, mount the stove door and test out the seal. Try firmly closing the door and check that you hear a muffled sound of the gasket (and not metal) hitting the body of the stove. If this is OK, do the "paper money" test. open the door and close a bill in the stove door so that half of it is inside the stove and the other half is outside. Make sure the door is latched. Try to pull the bill out. It should not slip out easily. If there is an area in the door where it slips out easily, then that part of the door seal needs redoing.