1. Worksheet 1.1 – Refrigerant circuit with restrictor (solution)
Correct procedures for working on air conditioning systems
1. Label the numbered components.
2. Use arrows to mark the flow of direction of the refrigerant.
3. What status (solid, liquid or gaseous) does the refrigerant have a points A and B in normal A/C operation?
4. Change the pressure and temperature to the values indicated.
Use the familiar sources of information to solve the task ….
A mainly gaseous
B liquid
1.4 bar and –5 °C 4 5
Ref. A – "generally" gaseous as the condition largely depends on the influx of heat at the evaporator. To ensure that the compressor definitely does not drawn in any refrigerant in liquid or droplet form, the reservoir features a dryer on the LP side. A 2 6 B 3 7 1
A/C compressor
Drain container with dryer
Extraction and charger valve
Low pressure switch
Evaporator
Restrictor
High pressure switch
Condenser 8
15.7 bar and 60 °C
VSQ/TT • TT • Status: For internal use only

2. Worksheet 1.2 – Refrigerant circuit with expansion valve (solution)
Correct procedures for working on air conditioning systems
1. Label the numbered components.
2. Use arrows to mark the flow of direction of the refrigerant.
3. What status (solid, liquid or gaseous) does the refrigerant have a points A and B during normal A/C operation?
4. Change the pressure and temperature to the values indicated.
Use the familiar sources of information to solve the task ….
A gaseous
B generally liquid A 5
2.49 bar and 5 °C 4 7 8 1
20.0 bar and 70 °C 6
A/C compressor
Fluid reservoir with dryer
Condenser
Expansion valve
Evaporator
Pressure dump valve
Oil drain plug
Extraction and charger valve 2 3 B
VSQ/TT • TT • Status: For internal use only

3. Worksheet 1.3 – Refrigerant circuit with second evaporator (solution)
Correct procedures for working on air conditioning systems
1. Label the numbered components.
2. Use arrows to mark the flow of direction of the refrigerant.
3. What status (solid, liquid or gaseous) does the refrigerant have a points A and B during normal A/C operation?
4. Change the pressure and temperature to the values indicated.
Use the familiar sources of information to solve the task ….
A gaseous
B liquid
4.7 bar and 20 °C 5 4 B
If the participants are interested, the role and function of the refrigerant temperature sender G454 can be explained. Installation of the sensor depends on the engine. Further information can be found in SSP 301 Touareg heating and air conditioning system. 6 3 9 11 7 2 1 A
A/C compressor
Refrigerant temperature sender G454
Drain and charger valve
Expansion valve II
Evaporator in rear
Evaporator temperature sensor 308
High pressure sender G65
Condenser
Expansion valve I
Fluid reservoir with dryer
Evaporator 8 10
4.7 bar and 20 °C
VSQ/TT • TT • Status: For internal use only