2. Start the engine and let it run at a crankshaft speed of 2000 rpm, set the temperature switch to the position corresponding to the supply of the coolest air to the passenger compartment, and the fan switch to the position corresponding to the maximum rotation speed.
3. Open all windows and doors.
4. Place a dry thermometer into the nozzle supplying cooled air to the passenger compartment.
5. Place the psychrometer at the air intake point in the air conditioner refrigeration circuit.
6. Check the high pressure gauge readings, which should be between 1.373-1.575 kPa. If the readings exceed the upper limit specified, pour water on the condenser. If the readings are below the lower limit, cover the front of the condenser.
7. Check the dry thermometer readings, which should be within 25-35°C.
8. Determine the relative humidity of the air using the psychrometric graph by comparing the temperatures of the wet and dry thermometers of the psychrometer placed at the air intake of the air conditioner.
9. Determine the temperature using a dry thermometer placed in the nozzle supplying cooled air to the passenger compartment and calculate the difference between the temperature values using a dry thermometer at the air intake and using a dry thermometer at the air outlet to the passenger compartment.
10. Make sure that the intersection point of the relative humidity and temperature difference lines is within the black shaded area, which indicates that the cooling capacity characteristics are within the standard.
