NANO

842 HVAC TROUBLESHOOTING AND DIAGNOSIS In order to find the causes of troubles as quickly as possible, it is necessary to conduct troubleshooting using a rational method and procedure. Before starting troubleshooting, first confirm the symptoms as follows: (a) Start the engine and keep it idling. Then turn the blower switch and AC switch on, and check the AC working conditions. (b) Check the blower operation, the magnetic clutch operation andAC outlet air temperature. (c) Check the condenser fan working with AC ‘ON’ , condenser fan should switch ‘ON’. After confirmation of symptoms, conduct the following rational method of troubleshooting. 10.7.1 Visual and Audio Inspection The simplest way to detect troubles is by looking and listening. (a) Is the AC belt loose? (b) Are the condenser fins covered with dirt and dust? In this case, the condenser cooling effect will be greatly reduced. As a result, the cooling capacity will also decrease. (c) Is the AC filter clogged? A clogged AC filter will reduce the air flow and lower the cooling capacity. (d) Can oil stains be seen in the refrigeration cycle connections and joints? A place that shows an oil strain indicates that the refrigerant is leaking from that place together with compressor oil.