The working principle of instantaneous electric water heater is mainly based on the rapid heating of water flow by the internal electric heating element. The following is a detailed description of the working principle:

　　Core components

　　Heating Tube: The core component of the instantaneous electric water heater is the heating tube, which is usually made of stainless steel and other corrosion-resistant materials with good thermal conductivity. The heating tube is responsible for the conversion of electrical energy into heat energy.

　　Heat exchanger: Some instantaneous electric water heaters are also equipped with heat exchangers, usually made of copper or aluminum and other materials with excellent thermal conductivity. The role of the heat exchanger is to transfer the heat generated by the heating tube to the cold water flowing through, thus realizing the rapid heating of water.

　　Workflow

　　Cold water entry: when the user opens the faucet, the cold water first enters the instantaneous electric water heater.

　　Heating process:

　　Direct heating type: when the cold water passes through the groove plate or conduit inside the water heater, it will directly contact with the electric heating element. The electric heating element warms up quickly after being energized, and transfers the heat to the cold water, so that it is heated to the preset temperature in a short period of time.

　　Heat exchange type (such as equipped with a heat exchanger): Cold water first flows through the heat exchanger, and the heat generated by the heating tubes inside the heat exchanger is transferred to the cold water by heat conduction or convection to realize the heating of the water.

　　Hot water output: The heated hot water flows out through the outlet of the water heater for users' use.

　　Safety and regulation mechanism

　　Thermostat: Instantaneous electric water heaters are usually equipped with a thermostat to monitor the temperature inside the water heater. When the temperature reaches a preset value, the thermostat will automatically cut off the power supply to prevent the water temperature from becoming too high and causing safety problems.

　　Water flow control device: Some water heaters are also equipped with a water flow control device, which automatically adjusts the power of the heating pipe according to the water flow when the user turns on the faucet to ensure that the water is heated within a short period of time while maintaining a constant water temperature.

　　Work characteristics

　　Fast heating: Instantaneous electric water heaters work very fast, usually only a few seconds to heat cold water to the appropriate temperature.

　　Energy saving and environmental protection: Because of the instant heating method, it avoids the waste of energy caused by the long time keeping warm of the traditional storage water heater.

　　Space saving: relatively small size, suitable for installation in places with limited space.

　　In summary, instantaneous electric water heater through the internal electric heating element for rapid heating of water flow, and equipped with thermostat and water flow control device to ensure the use of safe and constant water temperature. Its fast heating, energy-saving and space-saving features make it widely used in modern households.