Air conditioner with refrigerating medium lack and accident detection functions and method for detecting accidents

The invention relates to an air-conditioner and faulty diagnoses method for air-conditioner, especially the air-conditioner with detecting performance for lacking refrigerant and faulty detecting method for lacking refrigerant in air-conditioner. The air-conditioner with detecting performance for refrigerant lacking comprises compressor, heat exchanger outside, restricting element, heat exchanger inside, central processing unit and faulty detecting mechanism for lacking refrigerant, which comprises temperature sensor for pipe which is set in the middle of refrigerant pipe of heat exchanger inside, temperature sensor for circumstance which is set at the windward side of heat exchanger inside and comparing unit which is connected to central processing unit. Because by detecting for pipe and circumstance temperature simply the air-conditioner can estimate the lack of refrigerant or system jamming there is no need to detect current and it is no relation with the specification of compressor. The method is simple and stable.