1) check the power supply voltage is 220V. 

 

2) control switch of the indoor unit allocated to the "stop" position, and the thermostat switch to labeled "low" position on the scale card. 

 

3) Turn on the power, the control switch to the "strong wind" position, turn the unit off. Fans observe the work of the air conditioning unit, then there should be no noticeable impact sound or noise. 

 

4) The switch to "high cold" file to see whether the unit started cooling operation.