Constant-temperature pre-heating and instant-heating multi-mode quick-heating electric water heater

The utility model provides a constant-temperature pre-instant multi-mode quick-heating electric water heater. A pre-heating electric heating tube is arranged in a water storage liner of the constant-temperature pre-instant multi-mode quick-heating electric water heater; the water storage inner container is provided with an inner container water inlet pipe and an inner container water outlet pipe, the constant-temperature instant-heating integrated assembly comprises a constant-temperature water mixing valve, a cast aluminum type instant-heating device, a water heater water inlet pipe and a water heater water outlet pipe, and an instant-heating electric heating pipe and an instant-heating heat exchange pipe are arranged in the cast aluminum type instant-heating device; the water heater water inlet pipe is communicated with the liner water inlet pipe; the water heater water outlet pipe is arranged near the cast aluminum type instant heating device, is aligned with the water heater water inlet pipe at an interva