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-011-0808 • Status: 08.2008 For internal use only

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-011-0808 • Status: 08.2008 For internal use only

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-011-0808 • Status: 08.2008 For internal use only