Abstract: A fuel-air combustion chamber with improved mounting and thermal distribution features. The combustion chamber is formed with a flange adapted for receiving a plurality of retainer rings therearound for direct securement of the flange to a burner mounting plate adjacent a fuel-air nozzle for generating heat within the combustion chamber. The combustion chamber is also temporarily supported within the furnace housing by a combustible support leg affixed thereto. In this manner, the combustion chamber is supported during shipping and handling by a support leg which is automatically disintegrated during use of the combustion chamber.