Volkswagen Tiguan Service and Repair Manual: Components, Replacing
General Information
- All components of the refrigerant circuit submitted for quality
observation are always to be sealed (use original sealing caps of original
part).
- To date, the original parts (compressor, reservoir, receiver/dryer,
evaporator and condenser) have been filled with nitrogen gas. This charging
stops gradually or the charging pressure is so low that gas does not escape
noticeably when opening.
- On vehicles installed with a compressor with no A/C clutch, the engine
is only to be started following complete assembly of the refrigerant circuit
(compressor always in operation as well).
- So that the compressor with A/C Compressor Regulator Valve -N280-
(without A/C clutch) is not damaged when the refrigerant circuit is empty,
it is equipped with a secured oil supply. This means that approximately 40
to 50 cm3 of refrigerant oil remains in the A/C
compressor.
Note
- As original parts are sometimes stored for lengthy periods and at
different locations within the spare parts organization, it is entirely
possible that gas will escape from some parts and not from others on initial
opening (even in the case of identical original part numbers). Sealing caps
at original part connections are therefore to be removed carefully and the
nitrogen gas allowed to escape slowly.
- The refrigerant circuit is equipped either with a restrictor and
accumulator or with an expansion valve and receiver/dryer.
- Seal open connections and pipes (to prevent absorption of moisture).
- Always replace the restrictor.
The reservoir/receiver/dryer or dryer bag/cartridge should not be replaced
under the following conditions.
- After an accident when there is no damage on the
reservoir/receiver/dryer.
- 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/receiver/dryer or dryer cartridge should be replaced under the
following conditions.
- The refrigerant circuit was opened and the vehicle is older than 5
years.
- The refrigerant circuit has been opened for an indefinite period of time
(slow leak).
- The repair exceeded the normal repair time and moisture has entered.
- Always replace the receiver/dryer 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.
- The A/C compressor has locked up.
- The reservoir/receiver/dryer is damaged (accident).
Leaking or Damaged Components except A/C Compressor, Reservoir or
Receiver/Dryer
Empty Refrigerant Circuit
- Remove malfunctioning component.
- Remove the A/C compressor.
- Remove oil drain plug from A/C compressor.
Note
- To speed up refrigerant oil drainage, turn A/C compressor by hand via
ribbed belt or magnetic clutch plate.
- Pour the used refrigerator oil out of the A/C compressor.
- Then fill the A/C compressor with quantity of fresh refrigerant oil
corresponding to quantity of refrigerant oil in original part compressor.
- Use different refrigerant oils and quantities for the various
compressors.
- To ensure the compressor is lubricated at start-up, at least 80 cm3
of refrigerant oil must be poured into the compressor. The remainder can be
added to the new reservoir or receiver/dryer.
- If dirt has penetrated into the compressor with the refrigerant circuit
open (for example after an accident), compressor is to be replaced.
- Flush the refrigerant circuit with compressed air and remove moisture
with nitrogen.
- Replace receiver/dryer or accumulator and restrictor.
- Assemble, evacuate and recharge refrigerant circuit.
Refrigerant Still in Circuit
- Discharge the refrigerant circuit.
- Remove malfunctioning component, flush with compressed air, collect
escaping refrigerant oil.
- The new component is to be filled with the amount of refrigerant oil
flushed out (plus 20 cm3 for evaporator, plus 10
cm3 for condenser, refrigerant pipes and
refrigerant hoses) as fresh refrigerant oil fill.
- Replace the restrictor depending on the vehicle.
- Assemble, evacuate and charge the refrigerant circuit.
A/C Compressor, Replacing
Flushing Not Necessary
Note
For vehicles with an electrically-driven A/C compressor, de-energize the high
voltage system before removing the A/C compressor.
- Discharge the refrigerant circuit.
- Remove the A/C compressor.
Note
If a different A/C compressor is installed with a different refrigerant oil,
the refrigerant circuit is to be flushed with refrigerant R134a.
Electrically-driven A/C compressor:
If an electrically-driven A/C compressor is being replaced that does not have
a mechanical fault (for example, a faulty circuit board), then determine how
much refrigerant is in this A/C compressor.
Note
- This A/C compressor must be flushed to get all the refrigerant oil out.
- The A/C compressor is flushed in the flow direction (from the low
pressure side input to the high pressure side output)
- So that as much refrigerant oil as possible is flushed out of the A/C
compressor, the A/C compressor must be positioned so that the high pressure
side output is as low as possible.
- 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
2 kg refrigerant each and extract refrigerant again, evacuate).
Quantity: for example 50 cm³
Pour so much refrigerant oil out of the new A/C compressor so that only the
amount remains (plus 10 cm 3) that had been flushed
out of the old A/C compressor beforehand. If the new original A/C compressor has
for example, 200 cm3, then only pour out 140 cm3.
- Pour old refrigerant oil out of A/C compressor. Handling refrigerant
oil.
Note
In not enough refrigerant oil can be poured out from the A/C compressor to be
installed, flush the new A/C compressor. After flushing, fill the A/C compressor
to be installed with as much new refrigerant oil as was flushed from the
replaced A/C compressor.
Mechanically Driven A/C Compressor:
- Remove oil drain plug from A/C compressor.
- To accelerate drainage of refrigerant oil, rotate compressor e.g. by way
of ribbed belt pulley/clutch plate of A/C clutch for example. Does not apply
to the electrically-driven A/C compressor.
- Pour old refrigerant oil out of A/C compressor. Handling refrigerant
oil.
- 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 cm3 of refrigerant oil
has been poured out of the malfunctioning A/C compressor and 220 cm3
out of the original part A/C compressor (a small quantity of refrigerant oil
remains in the A/C 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.
- If a greater quantity of refrigerant oil (more than approximately 80 cm3)
has been poured out of the malfunctioning compressor, the remaining
refrigerant oil can also be added to the evaporator or
reservoir/receiver/dryer.
- Replace the restrictor depending on the vehicle.
- Assemble, evacuate and charge the refrigerant circuit.
Leaks or Internal Damage, for Example Noises or No Output
Note
For vehicles with an electrically-driven A/C compressor, de-energize the high
voltage system before removing the A/C compressor.
- Discharge the refrigerant circuit.
- Remove the A/C compressor.
Note
- In the case of internal damage (on A/C compressor), flush refrigerant
circuit with refrigerant R134a.
- If a different A/C compressor is installed with a different refrigerant
oil, the refrigerant circuit is to be flushed with refrigerant R134a.
- Replace receiver/dryer/dryer cartridge and expansion valve or reservoir
and restrictor.
- If a leak is present, check the expansion valve for debris or corrosion
and replace if necessary.
- Assemble, evacuate and charge the refrigerant circuit.
Receiver/Dryer or Reservoir and Restrictor, Replacing
Contaminants Removed from Refrigerant Circuit
The reservoir/receiver/dryer or dryer bag/cartridge should not be replaced
under the following conditions.
- After an accident when there is no damage on the
reservoir/receiver/dryer.
- 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/receiver/dryer or dryer cartridge should be replaced under the
following conditions.
- The refrigerant circuit was opened and the vehicle is older than 5
years.
- The refrigerant circuit has been opened for an indefinite period of time
(slow leak).
- The repair exceeded the normal repair time and moisture has entered.
- Always replace the receiver/dryer 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.
- The A/C compressor has locked up.
- The reservoir/receiver/dryer is damaged (accident).
- Discharge the refrigerant circuit.
- Remove the 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 e.g. by way
of ribbed belt pulley/clutch plate of A/C clutch for example.
- Pour old refrigerant oil out of A/C compressor. Handling refrigerant
oil.
- Then fill compressor with quantity of fresh refrigerant oil
corresponding to quantity of refrigerant oil in original part compressor.
Note
- Which refrigerant oils and quantities are used for the various
compressors.
- To ensure the compressor is lubricated at start-up, at least 80 cm3
of refrigerant oil must be poured into the compressor. The remainder can be
added to the new reservoir or receiver/dryer.
- If dirt has penetrated into the compressor with the refrigerant circuit
open (for example after an accident), compressor is to be replaced.
- Replace receiver/dryer or accumulator and restrictor.
- Assemble, evacuate and charge the refrigerant circuit.
Specified Values
Note
Connecting service station.
Observe test requirements.
Bring engine speed up to 2000 RPM.
Pay attention to the A/C service station pressure gauge.
Note
High-press ...
Testing Equipment, Tools and Materials
Commercially Available Tools and Materials
Note
This list outlines the testers, tools and materials required for expert
refrigerant circuit repair work.
Caution ...