I have an Empire 15,000 BTU direct vent heater. The gasket at the inspection window lasts only a short time and then fumes are vented to the room instead of outside. Would furnace cement work just as well? How difficult would it be to get it apart if the pilot needed to be relighted? The heater has one of those piezo ignitors but due to faulty design or manufacture, it never worked so the inspection window must be opened to relight the pilot with a match. Is there a longer lasting material that I could cut for a gasket?
Bob