Water heating system

A water heating system, comprising:

• a tank for holding water to be heated;
• a combustion chamber adjacent to the tank;
• an exhaust pathway that includes a flue that is in communication with the combustion chamber and that extends through the tank;
• a burner disposed within the combustion chamber and operable to combust fuel, such that combustion gas is conveyed along the exhaust pathway;
• and
• a damper assembly that includes a damper disposed within the exhaust pathway, an actuator operable to move the damper between an open position and a closed position, and an exhaust pathway temperature sensor coupled to the exhaust pathway at a position that is upstream of the damper when the damper is in the closed position, wherein the exhaust pathway temperature sensor is configured to sense a temperature corresponding with a temperature of the combustion gas within the exhaust pathway;
• and
• control circuitry in communication with the exhaust pathway temperature sensor and configured to determine a temperature value corresponding with a temperature of water disposed within the tank proximate to a top of the tank based on the temperature sensed by the exhaust pathway temperature sensor.

A water heating system, comprising:

• a tank for holding water to be heated;
• a combustion chamber adjacent to the tank;
• an exhaust pathway that includes a flue that is in communication with the combustion chamber and that extends through the tank;
• a damper assembly that includes a damper disposed within the exhaust pathway and an actuator operable to move the damper between an open position and a closed position;
• a burner disposed within the combustion chamber and operable to combust fuel in a firing state of the water heating system, such that combustion gas is conveyed along the exhaust pathway from the combustion chamber, into the flue, and onward to the damper;
• a standing pilot burner disposed within the combustion chamber and operable to combust fuel in a standby state of the water heating system, such that combustion gas is conveyed along the exhaust pathway from the combustion chamber, into the flue, and onward to the damper;
• a standing pilot burner output sensor that senses a characteristic of an output of the standing pilot burner;
• and
• control circuitry in communication with the standing pilot burner output sensor that, in the standby state of the water heating system, controls the actuator of the damper assembly to move the damper from the closed position to the open position based on the sensed characteristic of the output of the standing pilot burner.