Flames from a chimney fire can generate temperature that exceed 2000?F. [2] Installing the weather-sealing, stainless steel cap on a Ventinox relined chimney.[3] The Ventinox system usually uses a stainless steel baseplate inside the smoke chamber. [4] To reline a chimney with the Insulcrete system, a bladder is inserted into the flue and inflated with an air compressor.