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A/C Refrigerant System, Component Overview



A/C Refrigerant System, Component Overview

HD = High pressure side
ND = Low pressure side







1 - A/C Compressor Regulator Valve N280
- Do not remove
- Checking activation and function

NOTE: The A/C Compressor Regulator Valve N280 is activated by the operating and display module, Climatronic Control Module J255 and controls the pressure on the low-pressure end of the refrigerant circuit.

2 - Compressor
- Removing refrigerant line at compressor/installing
- Replace O-rings at connections.
- To protect compressor, engine is only to be started following complete assembly of refrigerant circuit
- Removing ribbed belt
- Removing and mounting compressor (vehicles with 4 or 6-cyl. engine)
- Different compressors depending on country version and engine.
- On vehicles with 8-cyl. engine, the compressor is not driven via a belt, but rather by way of a shaft
- After the installation of a new compressor or adding fresh refrigerant oil (e.g. after blowing out the refrigerant circuit), give the compressor 10 turns by hand after installing and prior to initial start-up to prevent compressor damage
3 - Oil drain plug
- "Denso" compressors are installed with a sealing ring which is always to be replaced
- Tightening torque: 30 Nm
- Compressor must be removed before screwing out to drain off refrigerant oil. Crank compressor by way of pulley or drive unit to accelerate drainage of refrigerant oil
4 - Belt pulley/compressor drive unit
- Replacing belt pulley
- Checking and replacing compressor drive unit
5 - Pressure relief valve, 10 Nm
- Do not remove
6 - Circuit with valve
7 - High Pressure Sensor G65
- Checking signal
8 - Condenser
- Replace O-rings at connections.
- Removing and installing refrigerant lines
- Removing and installing condenser
9 - Closing cap
- With seal
- Reinstall after using service valve
10 - Service connection
- High pressure side
- For service station for measuring, discharging and recharging
11 - Bolt in refrigerant line
- Replace O-ring.
- Tightening torque: 15 Nm
12 - Restrictor
- O-ring (7.5 mm/1.5 mm)
- Replace restrictor with O-ring.
- Lubricate O-ring slightly with refrigerant oil before installing restrictor
13 - evaporator
- Replace O-rings at connections.
- Tightening torque: Hexagon nut 25 Nm
- Removing and installing refrigerant line
14 - Service connection
- Low pressure side
15 - Closing cap
- With seal
- Reinstall after using service valve
16 - Accumulator
- Replace O-rings at connections.
- Tightening torque: Socket-head bolt at block connection 25 Nm