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→Demand Water Heaters
* Water heats up in seconds
* The system shuts off when the water flow ends
=== Capacity ====
With a demand water heater you will never run out of hot water. Demand water heaters are rated by flow and the rise in water temperature. With a standard input temperature of 50° F (10°C), and hot water regulated at 120°F (49°C), the temperature rise is 70°F (39°C).
To select a demand heater, pick a model rated for the flow rate and input temperature (or temperature rise) you require.
==== energy Efficiency ==== Although the unit efficiency of a demand heater is only somewhat better than a tanked heater, the tanked heater must operate continuously while the demand heater operates intermittently.
=== Point of Use ===