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.
- 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 startup 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 byway 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