Working principle:
A high, medium, low or high or medium water level probe switch is installed in the water tank. The water level switch has a signal line connected. at the water replenishment valve. When the water level in the water tank is lower than the high-end or medium probe, the electric valve circuit is turned on and powered, and the electric valve opens the valve when the water level rises. reaches the high level switch of the water tank, the electric valve circuit is cut off and the spring inside closes the valve.