A water heating system, comprising: ∘ a burner assembly for providing a source of thermal energy, the burner assembly comprising a combustion chamber, an air intake to supply an air stream, an air fuel delivery system and a fuel inlet to supply fuel to said air fuel delivery system wherein said air stream and said fuel are mixed to form an air/fuel mixture, and a blower to blow said air fuel mixture into the combustion chamber where said air/fuel mixture is ignited to produce products of combustion; ∘ a heat exchanger assembly operatively coupled to the burner assembly, the heat exchanger assembly comprising a first fluid conduit in heat exchange relationship with a second fluid conduit; ∘ a water inlet conduit coupled to the heat exchanger assembly for supplying fresh water to be heated; ∘ a water exit conduit coupled to the heat exchanger assembly for delivering the heated water to a point of use; ∘ a bypass conduit connecting the water exit conduit to the water inlet conduit; ∘ a feed-forward temperature sensor positioned in the water inlet conduit between the heat exchanger assembly and the bypass conduit for monitoring the temperature of the mixed water entering the heat exchanger assembly; characterized in that it further includes: ∘ a pump operated at constant flow rate, disposed in the bypass conduit and continuously circulates at least a portion of the heated water from the water exit conduit to the water inlet conduit at a constant flow rate, thereby providing a mix of fresh water and recirculated water to the heat exchanger assembly; and ∘ a processor for controlling the operation of the burner assembly by a feed-forward control system to maintain the temperature of said heated water to the point of use, based at least on the monitoring of the water circulating in the inlet conduit, said monitoring of the water circulating in the inlet conduit being only temperature monitoring and being provided by at least the feed-forward temperature sensor. ∘ a burner assembly for providing a source of thermal energy, the burner assembly comprising a combustion chamber, an air intake to supply an air stream, an air fuel delivery system and a fuel inlet to supply fuel to said air fuel delivery system wherein said air stream and said fuel are mixed to form an air/fuel mixture, and a blower to blow said air fuel mixture into the combustion chamber where said air/fuel mixture is ignited to produce products of combustion; ∘ a heat exchanger assembly operatively coupled to the burner assembly, the heat exchanger assembly comprising a first fluid conduit in heat exchange relationship with a second fluid conduit; ∘ a water inlet conduit coupled to the heat exchanger assembly for supplying fresh water to be heated; ∘ a water exit conduit coupled to the heat exchanger assembly for delivering the heated water to a point of use; ∘ a bypass conduit connecting the water exit conduit to the water inlet conduit; ∘ a feed-forward temperature sensor positioned in the water inlet conduit between the heat exchanger assembly and the bypass conduit for monitoring the temperature of the mixed water entering the heat exchanger assembly; ∘ a pump operated at constant flow rate, disposed in the bypass conduit and continuously circulates at least a portion of the heated water from the water exit conduit to the water inlet conduit at a constant flow rate, thereby providing a mix of fresh water and recirculated water to the heat exchanger assembly; and ∘ a processor for controlling the operation of the burner assembly by a feed-forward control system to maintain the temperature of said heated water to the point of use, based at least on the monitoring of the water circulating in the inlet conduit, said monitoring of the water circulating in the inlet conduit being only temperature monitoring and being provided by at least the feed-forward temperature sensor.