Water heating device

A water heating device, comprising:

• a first heating cavity;
• and
• at least one second heating cavity;
• wherein the at least one second heating cavity is provided side by side at a side of the first heating cavity;
• a lower end of the first heating cavity and a lower end of each of the at least one second heating cavity are each axially and insertedly provided with a heater;
• an upper end of the first heating cavity is provided with a first connector configured to allow water to pass through;
• an end of the first connector is connected to a water inlet pipe;
• an upper end of each of the at least one second heating cavity is provided with a second connector configured to allow water to pass through;
• the first connector is connected to the second connector of one of the at least one second heating cavity adjacent to the first connector through a bypass pipe;
• the lower end of the first heating cavity is communicated with each of the at least one second heating cavity through a communicating pipe provided on a side of the lower end of the first heating cavity;
• and the second connector on a last one of the at least one second heating cavity along a water flow direction is communicated with a water outlet pipe.