The main units of the air conditioning system
1. Pressure switch; 2. Capacitor; 3. Compressor; 4. Dehumidifier
Attention! The air conditioning system is under high pressure. Until the complete removal of the refrigerant, it is forbidden to disconnect any hoses and remove the units of the air conditioning system. The removal of the refrigerant must be carried out in a car service.
Check and care
Caring for the air conditioner is reduced to the following procedures:
- checking the condition and tension of the compressor belt;
- checking the condition of hoses and tubes (highway to disconnect!);
- cleaning the intercostal spaces of the condenser;
- checking the system refrigerant charge.
The air conditioner should be turned on every month for about 10 minutes.
The most common cause of unsatisfactory air conditioner performance is insufficient refrigerant charge. If there is a noticeable increase in air temperature from the air conditioner, then check the completeness of the refrigerant charge.
Checking the refrigerant charge
1. Warm up the engine.
2. Move the temperature control lever to the position corresponding to the lowest temperature, set the fan to the highest speed.
3. Open the doors.
4. Check that the compressor starts, which produces a click from the magnetic clutch and the center part of the clutch begins to rotate.
5. After the system is operational, compare the temperature of the two compressor tubes.
6. If the temperature of the pipes to the touch differs little, then refrigerant charge is necessary.
7. With the air conditioner running, hold the thermometer to the center of the air outlet duct. The air temperature at the outlet of the duct should be 17–20°C lower than the ambient temperature.
8. If the ambient temperature is very high, such as 45°C, the air conditioner outlet temperature may reach 15°C.
9. If the temperature of the cooled air is higher than generally accepted, it is necessary to recharge the air conditioner with refrigerant.
10. Further checks on the air conditioner are beyond the scope of this manual and must be carried out by trained personnel.
11. Check the condition of the refrigerant through the sight glass (indicated by an arrow). The sight glass is mounted in the line from the water separator on the 80 series cars, on the 60, 62 series cars the window is located on the water separator.
12. If foaming is observed in the glass when the air conditioner is running, then the amount of refrigerant is not enough.
13. Be aware that bubbles may appear in the sight glass at high ambient temperatures, even with normal refrigerant charge.
14. When the air conditioner is turned off and the amount of refrigerant is normal, there is also a slight foaming in the sight glass, which subsequently disappears.
Heater
If there is no air heating in the heater, then the reasons may be the following.
- the thermostat does not close, as a result of which the liquid does not warm up enough and does not warm up the heater radiator well. Replace thermostat (see subsection 4.3);
- The heater hose is clogged, preventing fluid from flowing through the radiator. Disconnect the hoses and flush the radiator with a water jet from a hose;
- If water does not pass through the heater core during flushing, the heater core is clogged and must be replaced.
If the airflow from the air vents does not match the set fan speed, check the fuses, wiring, switch, motor resistor, and motor.
If air does not come out of the air duct outlets, proceed as follows.
1. Turn the ignition key to the ON position and turn on the fan. The noise of a running electric motor should be heard.
2. If the hum of the motor is not audible, or if the check shows that the switch and resistor block are OK, then the cause may be a malfunction of the motor.
3. If the mat is damp or coolant vapor is leaking through the vents, there is a leak in the heater core.
4. Replace heatsink (beyond repair).
5. Check the water separator drain hose for cleanliness.