Tankless water heater
A tankless heater warms incoming water as you use it. This gas-fired example shows the flow sensor, heat exchanger and hot outlet inside a wall-mounted unit.
- A hot tap opens. Water begins moving through the heater. A flow sensor detects demand and signals the unit to start heating.
- Heat transfers to the water. In this gas-fired example, a burner heats the exchanger. Water passes through it while the vent carries combustion exhaust outside.
- Hot water reaches the tap. Heated water leaves through the hot outlet. Heating stops when demand stops; delivery at the tap also depends on the pipe length.
