Expansion Valve: Service and Repair
WM 877019 Removing and installing expansion valve
Technical values
Preliminary work
WARNING
Refrigerant
- Danger of freezing
-> Avoid contact with refrigerant.
-> Wear personal protective gear.
-> Observe the safety regulations for working on air-conditioned vehicles and dealing with refrigerant.
-> Observe the safety regulations for extraction and filling systems.
-> Observe the instructions for repairing air conditioning systems and storing spare parts.
1. Drain refrigerant. -> 870317 Draining and filling refrigerant - section on "Draining" Service and Repair
2. Drain coolant. -> 193817 Draining and filling coolant - section on "Draining" Service and Repair
3. Remove wiper linkage. -> 921919 Removing and installing wiper linkage - section on "Removing" Service and Repair
4. Remove heat exchanger return hose. -> 803219 Removing and installing heat exchanger return hose - section on "Removing" 803219 Removing and installing heat exchanger return hose
5. Unscrew fastening screw on directional-control valve holder and swivel directional-control valve out of position. -> 827419 Removing and installing directional-control valve - section on "Removing" Service and Repair
6. Disconnect refrigerant connecting line at the expansion valve. -> 874519 Removing and installing compressor/evaporator line - section on "Removing" 874519 Removing and Installing Compressor-Evaporator Line
7. Disconnect refrigerant connecting line at the expansion valve. -> 874719 Removing and installing evaporator/condenser line - section on "Removing"
Removing expansion valve
Information
The description provided here relates to a vehicle with an auxiliary heater.
Installation position
1. Loosen fastening screws -1- on the expansion valve -2-.
Removing expansion valve
Information
The refrigerant connections must be closed off immediately using suitable stoppers once the refrigerant lines have been removed.
2. Pull off expansion valve in direction of travel and remove it -arrow-.
Installing expansion valve
Information
- Before the expansion valve is re-installed, the O-rings of the refrigerant lines must be checked for damage and replaced if necessary.
- Wet the O-rings of the refrigerant lines with refrigerant oil.
1. Check seals -1- on the refrigerant adapter -2- for damage and replace them if necessary.
Checking/replacing seals
2. Screw in expansion valve.
Carefully fit the expansion valve -2- on the refrigerant adapter -arrow-.
Screw in fastening screws -1-.
=> Tightening torque: 5.5 Nm (4 ftlb.)
Installing expansion valve
Subsequent work
1. Fasten refrigerant connecting line to the expansion valve. -> 874519 Removing and installing compressor/evaporator line - section on "Installing" 874519 Removing and Installing Compressor-Evaporator Line
2. Secure refrigerant connecting line at the expansion valve. -> 874719 Removing and installing evaporator/condenser line - section on "Installing"
3. Install heat exchanger return hose. -> 803219 Removing and installing heat exchanger return hose - section on "Installing" 803219 Removing and installing heat exchanger return hose
4. Position the directional-control valve and screw in fastening screw on directional-control valve holder. -> 827419 Removing and installing directional-control valve - section on "Installing" Service and Repair
5. Fill in coolant. -> 193817 Draining and filling coolant - section on "Filling" Service and Repair
6. Install wiper linkage. -> 921919 Removing and installing wiper linkage - section on "Installing" Service and Repair
7. Fill in refrigerant. -> 870317 Draining and filling refrigerant - section on "Filling" Service and Repair
8. Bleed the cooling system. -> 190101 Checking the cooling system - section on "Bleeding" Component Tests and General Diagnostics