Abstract: A combustion apparatus. Combustion means (burner) generates flame by combustion. Air supply means (intake fan) supplies air to the combustion means. Flame current detecting means (FRB) is set at a certain detection position and detects a flame current value included in the flame which is generated by the combustion means. Determination means (control device) determines a distribution where the flame current value that is detected is included for the flame current detecting means. Control means (control device), when the flame current value is not included in a distribution, which is set as normal values, outputs a control command of increasing or decreasing at least one of the supply of the air by the air supply means and the supply of fuel based on a determination result by the determination means.

Abstract: A water heater includes combustion means (burner) that combusts fuel and generates exhaust; heat exchange means (primary heat exchanger and secondary heat exchanger) that exchanges heat of the exhaust for supplied water; bypassing means (bypass pipe) that makes the supplied water flow to an outlet of the heat exchange means; exchanged heat temperature detection means (exchanged heat temperature sensor) that detects temperature of the supplied water after heat exchange; flow rate adjustment means (bypass valve) that adjusts a volume of the supplied water flowing into the bypassing means and the heat exchange means; and a control unit that controls the flow rate adjustment means so as to make a predetermined volume of the supplied water or over flow to the heat exchange means.

Abstract: A combustion apparatus. Combustion means (burner) generates flame by combustion. Air supply means (intake fan) supplies air to the combustion means. Flame current detecting means (FRB) is set at a certain detection position and detects a flame current value included in the flame which is generated by the combustion means. Determination means (control device) determines a distribution where the flame current value that is detected is included for the flame current detecting means. Control means (control device), when the flame current value is not included in a distribution, which is set as normal values, outputs a control command of increasing or decreasing at least one of the supply of the air by the air supply means and the supply of fuel based on a determination result by the determination means.

Abstract: A water heater includes combustion means (burner) that combusts fuel and generates exhaust; heat exchange means (primary heat exchanger and secondary heat exchanger) that exchanges heat of the exhaust for supplied water; bypassing means (bypass pipe) that makes the supplied water flow to an outlet of the heat exchange means; exchanged heat temperature detection means (exchanged heat temperature sensor) that detects temperature of the supplied water after heat exchange; flow rate adjustment means (bypass valve) that adjusts a volume of the supplied water flowing into the bypassing means and the heat exchange means; and a control unit that controls the flow rate adjustment means so as to make a predetermined volume of the supplied water or over flow to the heat exchange means.

Abstract: There is provided a water heater unit realizing antifreezing of a water tube and the like of a heat exchanger without providing a backwind stopper on an exhaust tube. The water heater unit comprises a heat exchanger for heating water by a combustion heat of combustion means, water temperature sensors for detecting the temperatures of the water tube connected to the heat exchanger and an air supply fan for supplying air to a combustion chamber in which the combustion means is installed. When temperatures detected by the temperature sensors reach a temperature at which freezing of the heat exchanger is expected, the air supply fan is driven to supply air to the combustion chamber and the air is exhausted toward an exhaust port, thereby effecting heat exchange and antifreezing of the water tube.

Abstract: There is provided a water heater unit realizing antifreezing of a water tube and the like of a heat exchanger without providing a backwind stopper on an exhaust tube. The water heater unit comprises a heat exchanger for heating water by a combustion heat of combustion means, water temperature sensors for detecting the temperatures of the water tube connected to the heat exchanger and an air supply fan for supplying air to a combustion chamber in which the combustion means is installed. When temperatures detected by the temperature sensors reach a temperature at which freezing of the heat exchanger is expected, the air supply fan is driven to supply air to the combustion chamber and the air is exhausted toward an exhaust port, thereby effecting heat exchange and antifreezing of the water tube.