First, ensure that the water cooling system is functioning properly and that the alarm signal line of the chiller is connected to the machine.

Under normal conditions, the light strip on the front of the machine will turn yellow after the lid is fully closed, and it will turn red when the lid is opened. If the device keeps showing a red light, you need to check the four door protection switches(refer to the picture).

You can disconnect the wires of each switch and connect them together to see if the indicator light turns yellow. If it can turn yellow, it indicates that one of the switches is damaged, and you just need to replace the switch.

If all the switches have been shorted but the light still remains red, it is likely a failure of the Ruida expansion board or a wiring issue. Please contact customer service for handling.