1.The host does not run (1) Check whether the power supply is normal (2) check whether the power connected to the machine is open (3) confirm whether the machine is in the power on state (4) confirm whether the fuse is damaged 2. High noise (1) Check whether the host is firmly installed (2) check whether the host anti-vibration pad has been added (3）Check whether the motor is faulty (4）Check whether the cartridge needs to be replaced (5) Check whether the outdoor air outlet is blocked 3. Small air volume (1) Check whether the outdoor air outlet is blocked (2) Check whether the filter needs to be replaced (3) Check whether the indoor air outlet needs to be adjusted