Sensor block and automatic fill valve for water heater with immersed copper fluid coil

摘要

A pressureless electric water heater for domestic use has a cylindrical double-walled tank for holding a quantity of a heat transfer liquid such as water. Cold water enters a copper coil immersed in the heat transfer liquid. The heat transfer liquid is heated by an electric heating element that extends down from a hinged tank top. Cold water flowing through the immersed coil is heated by the heat transfer liquid and exits the coil as hot water. The hinged top allows easy access to the interior of the tank and to the heating element, further easing access and replacement thereof. Sedimentation in the tank is minimized because the tank water is rarely replaced. Sedimentation in the coil is reduced because pressurized water flows through the coil when hot water is required and continuously cleanses the tubing. A sensor block is used to activate the heating element whenever water is introduced into the coils. An automatic fill valve maintains the tank level. A top-nesting container can hold the heating element and thermostat, allowing for easier repairs.