TANKLESS WATER HEATERS EXPLAINED
How do tankless water heaters work?
Tankless water heaters put ultra-high-efficiency propane to work. Here’s how:
When you turn on your hot water faucet, a flow sensor activates a propane gas burner. This heats the water. This keeps going until you shut the water off, at which point the gas burner shuts off.
Take a closer look at how a tankless water heater works:


Leading water heater manufacturer Navien has provided this illustration of how a tankless water heater works.