
Contents
00 - Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1 General notes on the air conditioning system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Important instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Further documentation and information means . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Principles of the air-conditioning technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.4 Advantages of the air conditioning system - comfort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5 Operation of the air conditioning system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.6 Refrigerant R134a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.7 Vapour pressure table for refrigerant R134a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.8 Properties of refrigerant R134a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.9 Evidence of leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.10 Refrigerant oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.11 General occupational safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.12 Using pressure tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.13 Safety precautions when working with extraction and filling systems . . . . . . . . . . . . . . . . 12
1.14 Safety measures when working on vehicles with air conditioning system and when using
refrigerant R 134a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.15 Basics for working on the refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2 General instructions for refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.1 Components of the refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.2 Extractor, filler and measurement valves for quick couplings of the AC service station on the
refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.3 Pressures and temperatures in the refrigerant circuit and its arrangement . . . . . . . . . . . . 24
2.4 Switch and sender on the refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.5 Electrical components which are not fitted on the refrigerant circuit . . . . . . . . . . . . . . . . . . 29
2.6 The inspection and measurement work can be performed using the pressure gauge . . . . 30
2.7 Air conditioning service and recycling equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.8 Repair and maintenance instructions for refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . 31
3 Legal texts and legal regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.1 Laws and regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.2 Verification procedure of refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4 Refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
4.1 Important repair instructions for air conditioning systems . . . . . . . . . . . . . . . . . . . . . . . . . . 35
5 Working with the A/C service station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
5.1 Important instructions for working with the A/C Service station . . . . . . . . . . . . . . . . . . . . . . 37
5.2 Connecting the A/C service station to the refrigerant circuit for measuring and testing . . . . 38
5.3 Empty the refrigerant circuit with the A/C service station. . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.4 Evacuate the refrigerant circuit with the A/C service station. . . . . . . . . . . . . . . . . . . . . . . . . 39
5.5 Fill the refrigerant circuit with the A/C service station. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.6 Operate the air conditioning system after filling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.7 Fill refrigerant into the reservoir (filling cylinder or reservoir bottle) of the A/C service
station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.8 Draining the A/C service station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6 Leak detection on the refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.1 Looking for leaks in the refrigerant circuit - important instructions . . . . . . . . . . . . . . . . . . . . 42
6.2 Leak detection on the refrigerant circuit with compressed air or nitrogen . . . . . . . . . . . . . . 43
6.3 Detecting leaks on the refrigerant circuit with the leak detector VAG1796 . . . . . . . . . . . . 45
6.4 Detecting leaks on the refrigerant circuit with the leak detector VAS 6196 or VAS 6201A
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
7 Removing contaminants from the refrigerant circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
7.1 Cleaning the refrigerant circuit with compressed air and nitrogen . . . . . . . . . . . . . . . . . . . . 52
7.2 Cleaning refrigerant circuit with refrigerant R134a (flush) . . . . . . . . . . . . . . . . . . . . . . . . . . 54
7.3 Principle circuit diagrams for different rinsing cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Citigo 2012 ➤ , Fabia 2000 ➤ , Fabia II 2007 ➤ , Fabia II 2009 ➤ , Fab ...
Air conditioning system with refrigerant R134a - Edition 10.2014
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