a method of controlling no x emissions from a glass melting process in which combustion fuel produces exhaust gas in a melting furnace including no x compounds is disclosed . furnace exhaust gas passes from the melting furnace through a regenerator to a zone downstream from the regenerator . ammonia is injected into the furnace exhaust gas at the downstream zone while the furnace exhaust gas is within a desired temperature range to reduce the amount of no x compounds . additional gas is introduced into the furnace exhaust gas as it moves from the regenerator to the downstream zone whenever the furnace exhaust gas has a temperature which is outside the desired temperature range at the downstream zone so as to modify the furnace exhaust gas temperature such that the furnace exhaust gas is within the desired temperature range when furnace exhaust gas reaches to the downstream zone . in one particular embodiment of the invention , the additional gas is the exhaust from an excess air burner which is injected into the furnace exhaust gas at a temperature such that the furnace exhaust gas and the injected gas have a combined temperature between about 870 to 1090 ° c . at the downstream zone .