A system and method of producing oil is provided. The system includes a support module that provides air, water and fuel to a well. A steam generator is fluidly coupled to the support module to receive the air, water and fuel. The steam generator includes an injector having a plurality of tubes. The tubes have an outer surface with an oxidation catalyst thereon. The steam generator is configured to divide the supplied air and direct a first portion through the tubes. A second portion of the supplied air is mixed with supplied fuel and directed over the outside of the tubes. The air and fuel is burned in a combustor and water is sprayed on the combustion gases to produce steam. The steam and combustion gases are directed in the direction of the oil reservoir.