Activation by Water Demand: The sequence starts when you turn on a hot water tap or an appliance that requires hot Water, like a shower or dishwasher. This demand for hot Water signals the activation of the tankless water heater. Unlike tank-based systems that maintain an extensive reservoir of heated Water, tankless water heaters only heat Water when needed.

Water Flow Sensor: Once the system detects water demand, a flow sensor activates. This sensor measures the rate of Water flow through the unit and sends a signal to the control board, which determines the appropriate power or gas input required to heat the Water to the set temperature.

Heat Exchanger Activation: The Water flows through a heat exchanger, which is the critical component responsible for heating the Water. For gas-powered tankless heaters, a gas burner ignites, generating heat that transfers to the heat exchanger. In electric models, heating elements are used instead. The heat exchanger efficiently heats the cold Water passing through it, bringing it to the desired temperature in seconds.

Temperature Control: A temperature sensor monitors the Water's temperature as it exits the heat exchanger. This ensures that the Water reaching your faucet is at the preset temperature. The control board adjusts the gas flow (in gas units) or electricity input (in electric units) to maintain the proper water temperature, preventing overheating or underheating.

Hot Water Delivery: Once heated, the Water travels through your plumbing system to the requested faucet or appliance. The process is continuous, meaning as long as the water flow sensor detects water movement, the tankless water heater will keep supplying hot Water.

System Shutdown: When the hot water tap is turned off or the demand for hot water stops, the flow sensor signals the control board to shut down the heating process. The gas burner or electric element turns off, and the Water stops flowing through the unit. This immediate shutoff ensures that no energy is wasted.