Patent ID: 7477836

Claim:
A tankless water heater comprising: a sensitive flow sensor having an adjustable magnetic sensor and a plunger, the plunger having an imbedded magnet, the plunger configured to lift in a direction of the adjustable magnetic sensor absent of a resilient member in response to a flow of water thereby changing a state of an output of the sensitive flow sensor, the adjustable magnetic sensor adjustable from outside of the sensitive flow sensor, the plunger urged downward onto a rim solely by a force of gravity during an absence of the flow of water and the sensor having a surface interfacing with the rim wherein the surface angles upwardly towards an outer circumference of the plunger; at least one electric water heating element situated within a tankless water heating chamber; and the sensitive flow sensor and the tankless water heating chambers fluidly connected in series between a supply of water and at least one hot water spigot; whereas the change of the output of the sensitive flow sensor energizes the at least one electric water heating element, thereby heating the water.