General, Technical Data - HVAC: Maintenance Volkswagen Eos I

NOT REPLACING RESERVOIR/FLUID RESERVOIR OR DRYER BAG/CARTRIDGE, CONDITIONS

1. After an accident when there is no damage on the reservoir/fluid reservoir.
2. The repair was done quickly (not beyond the normal repair time) and no moisture has entered. The vehicle is not older than 5 years.

REPLACING RESERVOIR/FLUID RESERVOIR OR DRYER CARTRIDGE, CONDITIONS

1. The refrigerant circuit was opened and the vehicle is older than 5 years.
2. The refrigerant circuit has been opened for an indefinite period of time (slow leak).
3. The repair exceeded the normal repair time and moisture has entered.
4. Always replace the reservoir or dryer cartridge after flushing with compressed air, nitrogen or refrigerant R134a. Leave original parts in their packaging as long as possible to minimize the amount of moisture they absorb.
5. The A/C compressor has locked up.
6. The reservoir/fluid reservoir is damaged (accident).

REFRIGERANT CIRCUIT, FLUSHING WITH COMPRESSED AIR AND NITROGEN

1. In order to be able to force moisture and other contaminants out of refrigerant circuit, compressed air and nitrogen (to force moisture out of refrigerant circuit) are to be used.
2. For the most part, blowing through the refrigerant circuit with compressed air and nitrogen requires significantly more work than flushing with refrigerant R134a. As flushing with refrigerant R134a cleans the components more efficiently, always flush in case of a complaint (blowing through should only be used for certain complaints and individual components).

Only individual components should be flushed if

1. There is no possibility of flushing the refrigerant circuit with refrigerant R134a.
2. Dirt or other contaminants are located in individual components of the circuit.
3. Vacuum reading is not maintained on evacuating a leak-free refrigerant circuit (pressure build-up due to moisture in refrigerant circuit).
4. Refrigerant circuit has been left open for longer than normal (for example following an accident).
5. Pressure and temperature measurements in the refrigerant circuit indicate the likelihood of moisture.
6. Stipulated by the vehicle-specific repair information. Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) following replacement of certain components.

Note. Blowing compressed air and nitrogen through the refrigerant circuit does not achieve the level of cleanliness as flushing with refrigerant R134a. Flushing with refrigerant R134a loosens the refrigerant oil and the components are then cleaner. Refer to REFRIGERANT CIRCUIT, FLUSHING WITH REFRIGERANT R134A . When blowing, working pressure must not exceed a maximum of 217 psi (15 bar), (also use a pressure reducer for compressed air if necessary).

Always flush components in direction opposite of refrigerant flow direction.

Restrictor, expansion valve, compressor, receiver and reservoir cannot be flushed with compressed air and nitrogen.

Remove dryer cartridge on condensers with dryer.

First blow out dirt with compressed air, then remove moisture from components with nitrogen.

Connect adapter to connect the pressure hose to the refrigerant circuit. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation .

Note the following points to prevent oil and moisture from entering the refrigerant circuit from the compressed air system.

1. The compressed air must be routed through a compressed air purifier for cleaning and drying. Use is therefore to be made of filter and dryer for compressed air (included in scope of delivery as tool for painting work).

1. For refrigerant lines with threads or union nut at connection, make use of Adapter -V.A.G 1785/1- up to Adapter -V.A.G 1785/8- for connection of 5/8" -18 UNF charging hoses. These adapters can be found in VW/Audi passenger vehicle adapter chest -VAS 6338/1- and Commercial vehicle adapter chest -VAS 6338/50-.

1. On refrigerant pipes without thread or union nut on the connection, use adapter from VW/Audi passenger vehicle set adapter chest -VAS 6338/1- as well as Commercial vehicle adapter chest -VAS 6338/50- or a standard blower pistol with rubber mouthpiece.

Note. Compressed air/nitrogen emerging from components is to be drawn off by way of an appropriate system (for example workshop extraction system). Certain contaminants cannot be removed or can only be removed insufficiently from the refrigerant circuit with compressed air. These contaminants can only be removed by flushing with refrigerant R134a. Refer to REFRIGERANT CIRCUIT, FLUSHING WITH REFRIGERANT R134A .

REFRIGERANT CIRCUIT, FLUSHING

Note. For vehicles in which no adapters fit on to the refrigerant pipes, a blower pistol with rubber mouthpiece is to be used to blow through individual components. Special care must be taken not to damage the connections (crushing or scratching). Evaporator is to be flushed via the connection for low-pressure pipe (large diameter) after removing expansion valve or removing restrictor. Always flush components in direction opposite of refrigerant flow direction. Check expansion valve and replace if dirty or corroded. If there are dark, sticky deposits in the components that cannot be removed with compressed air, replace these components. Thin, light grey deposits on the insides of refrigerant pipes do not impair the function of the components. After flushing, always replace receiver or reservoir and restrictor. Replace dryer cartridge or dryer on condensers with attached dryer.

REFRIGERANT CIRCUIT, FLUSHING WITH REFRIGERANT R134A

Special tools and workshop equipment required

1. Robinair A/C Service Unit -ROB134APF- or Rinsing device for refrigerant circuits -VAS6337/1-. The auxiliary function "Flush refrigerant circuit" and the refrigerant circuit flushing device required for it are present on these A/C service stations.
2. VW/Audi passenger vehicle set adapter chest -VAS 6338/1-. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .
3. Commercial vehicle set adapter chest -VAS 6338/50-. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .

Note. VW does not approve the use of chemicals to seal leaks in the refrigerant circuit. Chemicals used to seal leaks in the refrigerant circuit often react with air and the moisture in it. They cause deposits in the refrigerant circuit and the A/C service station and malfunctions in valves and other components that they come in contact with. These deposits cannot be removed completely from the components, even by flushing. Chemicals used to seal leaks in the refrigerant circuit usually cannot be detected from outside. The label that should be applied to identify it is often missing. Therefore be careful when working with if you do not know its service history.

1. Refrigerant circuit must be flushed with refrigerant R134a in order to force out contaminants (such as abraded material from a malfunctioning A/C compressor) as well as old refrigerant oil as efficiently and as cleanly as possible and without the need for extensive work.

Note. The procedure for flushing the refrigerant circuit is displayed in Volkswagen Service Net; Volkswagen TV; API Online; or Volkswagen TV Net; API/PKW under the book title Body and the program from June 8, 2005 Refrigerant Circuit, Flushing, Golf Plus.

The refrigerant circuit should be flushed with refrigerant R134a if

1. Dirt or other contamination is in the refrigerant circuit.
2. Vacuum reading is not maintained on evacuating a leak-free refrigerant circuit (pressure build-up due to moisture in refrigerant circuit).
3. Refrigerant circuit has been left open for longer than normal (for example following an accident).
4. The pressure and temperature measurements in the refrigerant circuit indicate the likelihood of moisture in the circuit.
5. In the event of doubt about the amount of refrigerant oil in the circuit. If the A/C compressor should be reinstalled, the refrigerant should be drained from the compressor via the oil drain plug. To facilitate this, the ribbed belt pulley or magnetic clutch plate on the A/C compressor should be rotated by hand. After flushing, the entire quantity of refrigerant oil specified by «MAINTENANCE, DIAGNOSIS»(ref-475589-S14760033182012052300000) should be added to the refrigerant circuit (50 grams directly in the A/C compressor). Note additional oil quantity for systems with a 2nd evaporator.
6. A/C compressor had to be replaced on account of internal damage (for example noise or no output).
7. Stipulated by the vehicle-specific repair information following replacement of certain components.

Note. If neither of the two A/C service stations listed above are available for use in the workshop, Refrigerant Circuit Flushing Device -VAS 6336/1- or Refrigerant Circuit Flushing Device -VAS 6337/1- (depending on the workshop A/C service station version) (minimum 7 kg refrigerant R134a in refrigerant bottle) can also be used to flush the refrigerant circuit. However, the flushing procedure must then be performed manually. Refer to FLUSHING SEQUENCE PROCEDURE (OCCURS AUTOMATICALLY ACCORDING TO A/C SERVICE STATION PROGRAM) . In vehicles with screw-connections on refrigerant circuit, Adapter -V.A.G 1785/1- up to Adapter -V.A.G 1785/8- from VW/Audi passenger vehicle set adapter chest -VAS 6338/1- or Commercial vehicle set adapter chest -VAS 6338/50- may be used. In vehicles with screw-connections on A/C compressor and on accumulator, two of the Adapters -V.A.G 1785/8- are required. A Charging hose -VAS 6338/31- with 5/8 -18 UNF connections and large internal diameter can be found in the adapter chests in order to be able to bridge components (it is commercially available).

Preparation

Discharge refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DISCHARGING WITH SERVICE STATION .

Remove A/C compressor. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation .

On a vehicle with restrictor and reservoir

Remove restrictor (specific to vehicle) and reconnect refrigerant pipes to each other. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation .

Remove reservoir (specific to vehicle). Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation and connect refrigerant pipes to each other (to do this, use adapter and Charge hose -VAS 6338/31-) from VW/Audi passenger vehicle set adapter chest VAS 6338/1. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Note. The reservoir could be flushed, but it requires too much refrigerant due to its large volume. When this refrigerant is extracted, the reservoir ices up severely and this prolongs the extraction process significantly.

On a vehicle with expansion valve and fluid reservoir

Remove fluid reservoir. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation (specific to vehicle, not required for all vehicles) and connect refrigerant pipes to each other (for this, use adapters and Charging hose -VAS 6338/31-). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Remove expansion valve. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation (specific to vehicle) and install the adapter for it. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Note. If no suitable adapter for the expansion valve is available in Adapter Set for Refrigerant Circuits -VAS 6338/1- or Commercial Vehicle Adapter Set Chest -VAS 6338/50-, the removed expansion valve can also be drilled open (the expansion valve must be replaced with a new one).

Note. Several components are to be removed from expansion valve before drilling open. Expansion valves are available in different versions. For version -A-, components -B-, -C- and -D- must be removed. Then separate regulating element -E- from component -D-. Then drill open expansion valve in area -F- using a suitable drill (6 mm diameter). For version -G-, parts -H-, -I- and -K- must be removed and then drill open area -L- using suitable drill (6 mm diameter). Clean the drilled open expansion valve of residue from the work (shavings). Install parts -B-, -C- and -D- for version -A- or -H- for version -G-.

Note. In vehicles with two evaporators, the circuit to the second evaporator must be disconnected from circuit of the first evaporator and must be flushed via a separate work procedure. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation and ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Flushing

Check refrigerant quantity in the refrigerant cylinder, there must be at least 15 lb (7 kg) of refrigerant R134a.

Note. If necessary, switch on the heater installed on the refrigerant cylinder for 30 minutes before the first flushing procedure. This increases pressure in the refrigerant cylinder and accelerates charging of the flushing circuit.

Drain the old oil container of the A/C service station.

Connect the supply hose (high pressure side) of A/C service station to the low pressure line leading to the A/C compressor (line with larger diameter) using an adapter. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Connect return hose (low pressure- or intake side) of A/C service station to output of refrigerant circuit flushing device.

Connect the input on the refrigerant circuit flushing device to the high pressure line leading to the A/C compressor (line with smaller diameter) using an adapter. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Note. Components are always flushed in the opposite direction of refrigerant flow when A/C system is in operation. Refer to FLUSHING CIRCUIT BLOCK DIAGRAMS . While flushing, contaminants from the refrigerant circuit enter the refrigerant circuit flushing device and the A/C service station and are absorbed by the filters and dryers installed there. Depending on the contaminant, these components are to be replaced in shorter intervals in line with operating instructions for A/C service station or refrigerant circuit flushing device. The filter in the refrigerant circuit flushing device depends on the type and degree of contamination in the flushed refrigerant circuit. It should be replaced after 2 flushing cycles, at the most. If a heavily contaminated refrigerant circuit is flushed (the refrigerant oil from the circuit is black and viscous or there are many shavings in the refrigerant circuit), the filter should be replaced after flushing. With a refrigerant circuit heavily contaminated in this way, it is wise to flush the circuit again after changing the filter. Depending on the type of contamination, dirt (old refrigerant oil and abraded material from A/C compressor) is deposited on the viewing glass(es). Clean viewing glass(es) after flushing and flush the refrigerant circuit once more with one flushing procedure as a check. Fluid refrigerant cannot be conducted with the necessary speed through the expansion valve, restrictor and desiccant bag of certain fluid reservoirs, therefore these components must be removed and replaced by an adapter. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation . Adapters for connecting A/C service station and for bridging certain components of refrigerant circuit, refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .

Switch on the service station and flush the refrigerant circuit (duration for one flushing cycle with three flushing procedures is approximately 1 to 1.5 hours for about 9 lb. (4kg) of coolant R134a).

Note. Perform flushing of refrigerant circuit according to operating instructions of the A/C service station. Depending on A/C service station version, the old oil container holds only approximately 125 cm 3 of refrigerant oil. In the event a system with a larger volume of refrigerant oil must be flushed, it may be necessary to empty the old oil container after the first flushing procedure of a flushing cycle. Observe the refrigerant which flows back from the refrigerant circuit. The refrigerant circuit is only clean when the refrigerant flows clear and completely colorless through the viewing glass(es) on the flushing device in the A/C service station. When flushing, the complete amount of refrigerant oil is washed out of the refrigerant circuit (except for minor remains which can be disregarded). If contamination is especially severe, it may be necessary to perform the flushing cycle twice (two flushing cycles with three flushing operations each). Before the second flushing cycle, the filter on the flushing device must be replaced.

FLUSHING SEQUENCE PROCEDURE (OCCURS AUTOMATICALLY ACCORDING TO A/C SERVICE STATION PROGRAM)

1. After switching on, the flushing circuit (refrigerant circuit with connecting hoses and refrigerant circuit flushing device) is first evacuated and the refrigerant circuit is simultaneously checked for leaks. Depending on A/C service station version, it is possible that manually switching to advance the program is required.
2. A prescribed amount of refrigerant (for example 9lb. (4 kg)) is filled into the evacuated flushing circuit via the high pressure side of the A/C service station (opposite the normal direction of flow during normal A/C system operation and thus on the low pressure side of vehicle refrigerant circuit). Depending on the version of the A/C service station, refrigerant is added until the flushing circuit is completely full. This can be detected by refrigerant no longer flowing in after a certain period of time.
3. After the prescribed quantity of refrigerant has been filled, for example. The heater for the refrigerant circuit flushing device is switched on (only in the event the refrigerant is extracted in gaseous form from the refrigerant circuit flushing device), depending on version of A/C service station and refrigerant circuit flushing device.
4. After the refrigerant has been extracted, the heater on the refrigerant circuit flushing device (if applicable) switches off, the refrigerant circuit may be evacuated again (depending on the version), and the refrigerant oil extracted from the refrigerant circuit is separated by the A/C service station after evacuating.
5. The sequence of filling refrigerant, extracting (and evacuating) is repeated twice (performed a total of three times).
6. After the third extraction, the flushing circuit is evacuated depending on the version of the A/C service station.

After the flushing cycle has ended, check the viewing glass(es) on the flushing device. If they are dirty, clean them according to the instructions for the flushing device or A/C service station. Perform one addition flushing cycle as a check. One flushing procedure is sufficient (approximately 30 min.)

Check pressure in refrigerant circuit, there must be no positive pressure in the refrigerant circuit (evacuate refrigerant circuit briefly once more if necessary).

Disconnect A/C service station connections from vehicle refrigerant circuit. There must be no positive pressure in the refrigerant circuit.

Replace these vehicle-specific components.

1. Restrictor and reservoir
2. Expansion valve and fluid reservoir or dryer cartridge in fluid reservoir

Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Description and Operation

Depending on the complaint, replace A/C compressor. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation or drain the remaining refrigerant oil from the removed A/C compressor. Refer to COMPONENT REPLACEMENT (replace refrigerant circuit components) and re-fill the prescribed quantity of fresh refrigerant oil. Refer to MAINTENANCE, DIAGNOSIS .

Note. A certain prescribed quantity of refrigerant oil is in the A/C compressor original part. On vehicles with two evaporators, a certain quantity of refrigerant oil must also be added to the circuit if necessary. Refer to MAINTENANCE, DIAGNOSIS . If the A/C compressor is not replaced, the quantity of refrigerant oil in the A/C compressor must be topped off to the prescribed capacity (tilt the refrigerant oil out and refill the prescribed quantity into the A/C compressor or refrigerant circuit). Refer to COMPONENT REPLACEMENT and MAINTENANCE, DIAGNOSIS .

Completely reassemble the refrigerant circuit. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation .

Evacuate and recharge refrigerant circuit according to specification. Refer to REFRIGERANT CIRCUIT, DISCHARGING WITH SERVICE STATION and REFRIGERANT CIRCUIT, CHARGING WITH SERVICE STATION .

Start up A/C system according to specification. Refer to [For engine(s) BPY, CCTA, BUB, CBFA] General Information and A/C SYSTEM, OPERATING AFTER CHARGING .

FLUID RESERVOIR

The receiver collects the fluid drops and then directs them in an uninterrupted stream to the expansion valve. Moisture which has entered the refrigerant circuit during repairs will be collected by the dryer bag in the reservoir.

Scheme 3

Note. Replace the reservoir if refrigerant circuit has been open for a long time (beyond the normal repair time) and moisture has penetrated inside, or if required due to a specific complaint. Refer to COMPONENT REPLACEMENT . Only remove sealing plugs shortly before installation. A dryer bag in an unsealed reservoir is saturated with moisture after a short period of time and unusable. When installing, note arrow for direction of flow if necessary.

The new generation of reservoirs are installed directly on the condenser and contain a dryer cartridge.

Scheme 4

Note. Replace the dryer cartridge if refrigerant circuit has been open for a long time (beyond the normal repair time) and moisture has penetrated inside, or if required due to a specific complaint. Refer to COMPONENT REPLACEMENT . Remove dryer cartridge from packaging shortly before installation. The dryer cartridge becomes saturated with moisture and unusable after a short time in an unsealed package.

FLUSHING CIRCUIT BLOCK DIAGRAMS

Note. The arrows in the following illustrations show the direction of refrigerant flow while flushing. During flushing, refrigerant flows in the opposite direction than during A/C system operation, therefore the high pressure side of A/C service station is connected to A/C compressor at low pressure side of refrigerant circuit. These block diagrams indicate a refrigerant circuit with restrictor and reservoir and a refrigerant circuit with expansion valve, fluid reservoir and a second evaporator (optional equipment on certain vehicles) Depending on the design of A/C service station, check-valves may be installed between refrigerant circuit and A/C service station. They guarantee the correct direction of refrigerant flow during flushing.

Refrigerant Circuit With Expansion Valve, Fluid Reservoir and Second Evaporator, refer to Refrigerant Circuit With Expansion Valve, Fluid Reservoir and Second Evaporator .

Flushing Circuit With E-Compressor, refer to Flushing Circuit With E-Compressor .

Refrigerant Circuit with Restrictor and Reservoir

Note. On vehicles with restrictor and reservoir, the restrictor and reservoir are removed. Restrictor refrigerant pipes are reassembled. Refrigerant pipes to the removed reservoir are connected with each other via two adapters and Charge hose -VAS 6338/31- (from VW/Audi passenger vehicle set adapter chest -VAS 6338/1-).

Scheme 5

1. A/C Service Station With electronics and a flushing program, for example Robinair A/C Service Unit -ROB134APF- with Air Conditioning Flush Tool -VAS6337/1A-. If an A/C service station without a flushing program is used, the procedure must be performed manually (evacuate, flush 3 times with at least 4 kg refrigerant each and extract refrigerant again, evacuate).
2. Refrigerant Hose Of A/C Service Station From high pressure side of A/C service station (mostly colored red) to low pressure side connection of A/C compressor on refrigerant circuit (larger diameter).
3. Adapter To Connection For Low Pressure Side On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
4. Low Pressure Side Connection On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . On refrigerant line from A/C compressor to reservoir.
5. Connection To Reservoir Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . On refrigerant line from A/C compressor to reservoir.
6. Adapter For Bridging The Removed Reservoir Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
7. Refrigerant Charge Hose, refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) Charge hose -VAS 6338/31- (from VW/Audi passenger vehicle set adapter chest -VAS 6338/1-) for example.
8. Adapter For Bridging The Removed Reservoir Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
9. Connection To Reservoir Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .
10. Evaporator
11. Component Location Of Restrictor Restrictor is removed. Remove restrictor. Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) .
12. Bolts In Refrigerant Line Bolt together again after removing restrictor. Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) .
13. Condenser
14. High Pressure Side Connection On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .
15. Adapter To Connection For High Pressure Side On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
16. Charge Hose For Refrigerant Circuit Flushing Device From connection to high pressure side of A/C compressor on refrigerant circuit (smaller diameter) to input of Refrigerant Circuit Flushing Device -VAS 6336/1- or Refrigerant Circuit Flushing Device -VAS 6337/1-.
17. Refrigerant Circuit Flushing Device Different versions and different construction, for example Refrigerant circuit flushing device -VAS 6336/1- or Refrigerant circuit flushing device -VAS 6337/1A-. With filter, viewing glass, security valve, heater, refrigerant container, etc. (depending on version). Depending on the construction of the A/C service station and of refrigerant circuit flushing device, a check-valve may be installed at output of refrigerant circuit flushing device (to guarantee correct direction of refrigerant flow during flushing).
18. Refrigerant Hose Of A/C Service Station From low pressure side of A/C service station (mostly colored blue) to output of refrigerant circuit flushing device.

Refrigerant Circuit With Expansion Valve, Fluid Reservoir and Second Evaporator

Note. This block diagram shows a refrigerant circuit with expansion valve, fluid reservoir and second evaporator (optional equipment on certain vehicles). On vehicles with expansion valve and fluid reservoir, the expansion valve is removed and replaced by an adapter. Depending on vehicle, fluid reservoir is flushed or dryer cartridge is removed. Depending on fluid reservoir version, it is to be removed and line connections to fluid reservoir are to be connected to each other with two adapters and a charging hose. On a vehicle with only one evaporator, the components as of position 16 are not installed or are not required.

Scheme 6

1. A/C Service Station With electronics and a flushing program, for example Robinair A/C Service Unit -ROB134APF- with Air Conditioning Flush Tool -VAS6337/1A-. If an A/C service station without program is used for flushing, the procedure should be performed manually. -- Extract the refrigerant, if necessary. -- Set up the Refrigerant circuit flushing device -VAS 6336/1- or Refrigerant circuit flushing device -VAS 6337/1A- between the service station and refrigerant circuit return line. -- Evacuate refrigerant circuit for 20 minutes and then charge with 4 kg refrigerant R134a. Then extract again and repeat the procedure 2 more times. If the refrigerant in the viewing glass(es) is not clear after the third attempt, an additional attempt is necessary.
2. Refrigerant Hose Of A/C Service Station From high pressure side of A/C service station (mostly colored red) to low pressure side connection of A/C compressor on refrigerant circuit (larger diameter).
3. Adapter To Connection For Low Pressure Side On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
4. Low Pressure Side Connection On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .
5. Adapter For The Removed Expansion Valve Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
6. Evaporator
7. Connection To Fluid Reservoir Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . Not present on vehicles with a dryer cartridge in fluid reservoir on condenser or a fluid reservoir installed in the condenser. Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) .
8. Adapter For Bridging The Removed Fluid Reservoir Not required for all vehicles. Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
9. Refrigerant Charge Hose, refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) Charge hose -VAS 6338/31- (from VW/Audi passenger vehicle set adapter chest -VAS 6338/1-) for example.
10. Condenser If a fluid reservoir with dryer cartridge is installed on the condenser, dryer cartridge must be removed (seal again the fluid reservoir on or in the condenser after removing). Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) . If fluid reservoir is built directly on the condenser, fluid reservoir is to be removed and replaced only after flushing. Refer to «[For engine(s) BPY, CCTA, BUB, CBFA] Removal and Installation»(ref-475571-S07865064812012052300000) .
11. High Pressure Side Connection On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) .
12. Adapter To Connection For High Pressure Side On Refrigerant Circuit Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . From VW/Audi passenger vehicle set adapter chest -VAS 6338/1-.
13. Charge Hose For Refrigerant Circuit Flushing Device From connection to the high pressure side of the A/C compressor on the refrigerant circuit (smaller diameter) to input of refrigerant circuit flushing device.
14. Refrigerant Circuit Flushing Device Different versions and different construction, for example, Refrigerant circuit flushing device -VAS 6336/1- or Refrigerant circuit flushing device -VAS 6337/1-. With filter, viewing glass, security valve, heater, refrigerant container, etc. (depending on version). Depending on the construction of the A/C service station and of refrigerant circuit flushing device, a check-valve may be installed at output of refrigerant circuit flushing device (to guarantee correct direction of refrigerant flow during flushing).
15. Refrigerant Hose Of A/C Service Station From low pressure side of A/C service station (mostly colored blue) to output of refrigerant circuit flushing device.
16. Adapter For Sealing Outlet To The Second Evaporator Only required for certain vehicles with optional equipment 2nd evaporator. From commercial vehicle set adapter chest -VAS 6338/50-.
17. Adapter For Sealing Outlet To The Second Evaporator Only required for certain vehicles with optional equipment 2nd evaporator. From commercial vehicle set adapter chest -VAS 6338/50-.
18. Low Pressure Side Connection On Refrigerant Circuit To Second Evaporator Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . Only present on certain vehicles with optional equipment 2nd evaporator.
19. High Pressure Side Connection On Refrigerant Circuit To Second Evaporator Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . Only present on certain vehicles with optional equipment 2nd evaporator.
20. Adapter For The Removed Expansion Valve On Second Evaporator Different versions depending on vehicle. Refer to «ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT»(ref-475566-S24085056722012052300000) . Only required for certain vehicles with optional equipment 2nd evaporator. From commercial vehicle set adapter chest -VAS 6338/50-.
21. Second Evaporator Only present on certain vehicles with optional equipment 2nd evaporator.

Flushing Circuit With E-Compressor

If an E-compressor is being replaced that does not have a mechanical fault (for example, a faulty circuit board), then determine how much refrigerant is in it.

Quantity: for example 50 cm 3

A new E-compressor is filled with 150 cm 3 refrigerant oil.

Pour 90 cm 3 out of the new E-compressor. 10 cm 3 is extra.

Note. The E-compressor must be flushed to get all the refrigerant oil out. The main wiring diagram shows the refrigerant circuit with E-compressor.

Scheme 7

1. A/C service station NOTE: Flushing the E-compressor is performed manually. -- Extract the refrigerant, if necessary. -- Empty the Service Station old oil container. NOTE: On some Service Stations, the oil is first separated in the vacuum phase and then it goes into the old oil container. -- Set the amount of refrigerant on the Service Station to 2 kg and the oil quantity to 0. -- Set up the Refrigerant circuit flushing device -VAS 6336/1- or Refrigerant circuit flushing device -VAS 6337/1A- between the service station and refrigerant circuit return line. -- Evacuate the refrigerant circuit for 10 minutes. Then observe the vacuum display. If the vacuum remains constant, then fill the circuit with 2 kg refrigerant R134a. Then extract again and repeat the procedure one more time.
2. Refrigerant Hose Of A/C Service Station From low pressure side of A/C service station (mostly colored blue) to output of refrigerant circuit flushing device.
3. Refrigerant Circuit Flushing Device Different versions and different construction, for example, Refrigerant circuit flushing device -VAS 6336/1- or Refrigerant circuit flushing device -VAS 6337/1-. With filter, viewing glass, security valve, heater, refrigerant container, etc. (depending on version). Depending on the construction of the A/C service station and of refrigerant circuit flushing device, a check-valve may be installed at output of refrigerant circuit flushing device (to guarantee correct direction of refrigerant flow during flushing).
4. Charge Hose For Refrigerant Circuit Flushing Device From connection to high pressure side of A/C compressor on refrigerant circuit (smaller diameter) to input of Refrigerant Circuit Flushing Device -VAS 6336/1- or Refrigerant Circuit Flushing Device -VAS 6337/1-.
5. Adapter To Connection For High Pressure Side On Refrigerant Circuit From VW/Audi passenger vehicle set adapter chest -VAS 6338/1- adapter number -6338/3-.
6. Refrigerant Line, High Pressure Side, From The E-Compressor -- Remove the centering pin.
7. E-compressor
8. Refrigerant Line, Low Pressure Side, To The E-Compressor -- Remove the centering pin.
9. Adapter To Connection For Low Pressure Side On Refrigerant Circuit From VW/Audi passenger vehicle set adapter chest -VAS 6338/1- adapter number -6338/6-.
10. Refrigerant Hose Of A/C Service Station From the high pressure side of the service station (mostly red) to the connection on the low pressure line above the engine to the E-compressor

SERVICE STATION, DRAINING

Note. If it is necessary to evacuate the A/C service station (for example, because contaminated refrigerant was extracted), always replace all filters and dryers. Only remove the filters and dryers from their air-tight packaging immediately before installing them to prevent moisture from entering. Refrigerant containers filled with contaminated used refrigerant are referred to as "Recycling containers". Always evacuate recycling cylinders before first charging with refrigerant. Refrigerant cylinders in which there is air must not be filled with refrigerant. Different refrigerant types must not be mixed together. Refrigerant mixtures cannot be reprocessed but must be disposed of. If there is any doubt about the composition of the contents of the container, the refrigerant recycling company is to be informed accordingly.

WITH EXPANSION VALVE, FLUID CONTAINER AND E-COMPRESSOR FOR HYBRID VEHICLES

Note. The E-compressor does not have an A/C compressor regulator valve -N280-. The E-compressor RPM does the regulating. The E-compressor has the control electronics and G-charger, that moves the refrigerant.

A pressure check is possible only with Vehicle diagnostic tester.

COMPRESSOR, FLUSHING NOT REQUIRED

Discharge refrigerant circuit.

Remove A/C compressor.

Remove oil drain plug from A/C compressor.

To accelerate drainage of refrigerant oil, rotate compressor, for example, by way of ribbed belt pulley/clutch plate of A/C clutch for example.

Pour old refrigerant oil out of A/C compressor. For information on handling refrigerant oil, refer to Volkswagen Service Net, Handbooks, Service Handbook; Protecting the environment; Emissions Protection.

Remove oil drain plug from original part compressor, pour out refrigerant oil and only add a quantity of fresh refrigerant oil equal to the amount poured out of the malfunctioning compressor.

Note. If, for example, 70 cm 3 of refrigerant oil has been poured out of the malfunctioning compressor and 220 cm 3 out of the original part compressor (a small quantity of refrigerant oil remains in the compressor). Fill the compressor to be installed with 70 cm 3 of refrigerant oil (use can be made of oil poured out of original part compressor). Use different refrigerant oils and quantities for the various compressors. Refer to MAINTENANCE, DIAGNOSIS . If a greater quantity of refrigerant oil (more than approximately 80 cm 3 ) has been poured out of the malfunctioning compressor, the remaining refrigerant oil can also be added to the evaporator or reservoir/receiver. Refer to MAINTENANCE, DIAGNOSIS .

Replace restrictor.

Assemble, evacuate and charge refrigerant circuit.

FLUID RESERVOIR OR RESERVOIR AND RESTRICTOR, WITH CONTAMINANTS REMOVED FROM REFRIGERANT CIRCUIT

The reservoir/fluid reservoir or dryer bag/cartridge should not be replaced under the following conditions.

1. After an accident when there is no damage on the reservoir/fluid reservoir.
2. The repair was done quickly (not beyond the normal repair time) and no moisture has entered. The vehicle is not older than 5 years.

The reservoir/fluid reservoir or dryer cartridge should be replaced under the following conditions.

1. The refrigerant circuit was opened and the vehicle is older than 5 years.
2. The refrigerant circuit has been opened for an indefinite period of time (slow leak).
3. The repair exceeded the normal repair time and moisture has entered.
4. Always replace the reservoir or dryer cartridge after flushing with compressed air, nitrogen or refrigerant R134a. Leave original parts in their packaging as long as possible to minimize the amount of moisture they absorb.
5. The A/C compressor has locked up.
6. The reservoir/fluid reservoir is damaged (accident).

Discharge refrigerant circuit

Remove A/C compressor.

Rectify cause of trouble.

Examine expansion valve for dirt or corrosion; replace if necessary

Remove oil drain plug from A/C compressor.

To accelerate drainage of refrigerant oil, rotate compressor, for example, by way of ribbed belt pulley/clutch plate of A/C clutch for example.

Pour old refrigerant oil out of A/C compressor. For information on handling refrigerant oil, refer to Volkswagen Service Net, Handbooks, Service Handbook; Protecting the environment; Emissions Protection.

Then fill compressor with quantity of fresh refrigerant oil corresponding to quantity of refrigerant oil in original part compressor. Refer to MAINTENANCE, DIAGNOSIS .

Note. Which refrigerant oils and quantities are used for the various compressors. Refer to MAINTENANCE, DIAGNOSIS . To ensure compressor lubrication on start-up, at least 80 cm 3 of refrigerant oil must be poured into the compressor, the remainder can be added for example to the new reservoir or receiver. Refer to MAINTENANCE, DIAGNOSIS . If dirt has penetrated into the compressor with the refrigerant circuit open (for example, after an accident), compressor is to be replaced.

Replace receiver or accumulator and restrictor.

Assemble, evacuate and charge refrigerant circuit.