Replacing Electric Air-Conditioning Compressor

WARNING: This page is about a different variant/trim than selected.

NOTE: Fill level too low

Risk of damage to components.
→ Do not start the engine.

→ Do not tow the vehicle.

NOTE: Too much or too little refrigerant oil in air-conditioning circuit.

Reduced cooling output.
Lack of lubrication and failure of the air-conditioning compressor.
→ If a new air conditioning compressor or a component in the circuit is replaced, the oil quantity must be checked and adjusted.

Information

All connection points must be completely clean.

The air-conditioning compressor must be dry (washing the vehicle) and no moisture must get into the air-conditioning compressor and lines.

The connection points must be closed off after they have been opened. Use the original transport caps.

Information

If the air-conditioning compressor is blocked or seized up, then additional steps must be carried out to ensure that the air-conditioning system is working. See section on Work steps for blocked or seized up air-conditioning compressor

Information

New air-conditioning compressors are pressurised and filled with the total oil quantity required for the refrigerant circuit!
The remaining oil quantity in the individual components must therefore be taken into account!
Refrigerant oil from the compressor or refrigerant oil removed by suction from a previously run air-conditioning system may no longer be used (special-category waste)!

Determining oil quantity on the "old" air-conditioning compressor

Open the caps on the high-pressure and low-pressure side and relieve pressure from the compressor.
Fill refrigerant oil from the air-conditioning compressor into the measuring cylinder via the connection openings.
The amount of refrigerant oil is referred to as "V" in the formula below.

Determining oil quantity on the "new" air-conditioning compressor

To drain refrigerant oil:
1. 1.1 First open the cap on the high-pressure and low-pressure side and relieve pressure from the compressor.
2. 1.2 Drain refrigerant oil from the air-conditioning compressor via the connection openings.
  The refrigerant oil must not be re-used, but must be disposed of in accordance with regulations.
To determine the refrigerant oil quantity:
1. 2.1 V _total = "V _removed " + "V _old " + 20 cm³
2. 2.2 V _total = Total volume for the new air-conditioning compressor
3. 2.3 V _removed = Volume of refrigerant oil removed by suction
4. 2.4 V _old = Volume of refrigerant oil in the old air-conditioning compressor
5. 2.5 20 cm ³ = Additional safety volume
To fill the air-conditioning compressor:
1. 3.1 Fill the determined refrigerant oil volume V_total into the air-conditioning compressor.
2. 3.2 Fill in refrigerant oil via the high-pressure or low-pressure side.
3. 3.3 Install air-conditioning compressor
  > 873419 Removing and installing air-conditioning compressor - section on "INSTALLING "