GAS WATER HEATER WITH INCREASED THERMAL EFFICIENCY AND SAFETY

摘要

A gas water heater having increased thermal efficiency comprises a water tank having a sealed combustion chamber thereunder. An atmospheric burner is located in the combustion chamber. A flue pipe extends from the sealed combustion chamber and through the water tank for heat exchange of hot atmospheric gas therein with water in the water tank. A heat exchanger is in communication with the combustion gases exiting the water tank to extract residual heat from the combustion gas in the flue pipe for mixture with ambient air to produce pre-heated combustion air. An air convection or draft inducing device directs the hot combustion air from the heat exchanger through a sealed conduit to direct the pre-heated combustion air to the combustion chamber.