Expansion valves

Expansion valves are essential components of the air conditioning system. They regulate the flow of refrigerant, enabling its efficient expansion and cooling of the air in the vehicle's cabin. The precise operation of these valves ensures the efficient operation of the entire air conditioning system and the thermal comfort of passengers. At the Global Parts automotive store, you'll find a wide selection of used car parts, including expansion valves, perfectly matched to brands such as BMW, Audi , Mercedes, Volkswagen, Mini, and others . An air conditioning expansion valve is a component installed between the condenser and the evaporator . Its function is to precisely lower the pressure of the refrigerant (usually R134a or R1234yf) and control the amount of refrigerant entering the evaporator. In practice, this means stabilizing the refrigerant's evaporation temperature at approximately 0–5°C, which enables effective heat extraction from the air supplied to the cabin. Expansion valves are used in both classic manual systems and automatic dual-zone air conditioning systems.

What are the functions of expansion valves ?

Expansion valves play a key role in the air conditioning system:

• Refrigerant Flow Control – Regulates the amount of refrigerant delivered to the evaporator based on system load.
• Reducing refrigerant pressure – They expand the refrigerant, allowing it to be effectively cooled in the evaporator.
• Improving air conditioning efficiency – Thanks to precise flow regulation, valves ensure optimal operation of the entire system.
• Protection of system components – Enables the system to operate smoothly, reducing the risk of overloading and damage to other components. Depending on the vehicle's design , mechanical expansion valves or solutions controlled indirectly by temperature and pressure sensors are used. For example , the BMW E60 air conditioning expansion valve and the Audi A4 B5 air conditioning expansion valve differ in body design, channel diameter, and mounting method, despite performing an identical function in the refrigerant circuit. Proper compatibility of the valve with the evaporator, compressor, and air conditioning lines is crucial for the stable operation of the entire system.

Why is it worth taking care of expansion valves ?

A malfunctioning expansion valve can reduce air conditioning performance and affect driving comfort. Typical symptoms include:

• No cooling – The air conditioning does not cool the air in the cabin, despite the compressor working properly.
• Evaporator Freezing – Excessive refrigerant in the evaporator can cause it to freeze.
• Irregular operation of the air conditioning – The system operates unstable, which affects the comfort of use.
• Increased fuel consumption – An inefficient valve can increase the load on the compressor, leading to increased fuel consumption. If replacement is necessary, Global Parts has the right used car parts to restore the full functionality of your air conditioning system.

Expansion valves – typical parameters and applications

Valve type	Type of AC system	Sample models	Scope of work
Mechanical TXV	Manual air conditioning	Audi A4 B5, VW Passat B5	0–5°C
Compact valve	Automatic air conditioning	BMW E60, Mercedes W211	0–6°C
Block valve	Two-zone systems	BMW, Audi, Mini	0–5°C

How to choose the right expansion valves ?

When selecting expansion valves, there are several key aspects to consider:

• Vehicle-specific fit – Every air conditioning system has its own specific technical requirements. At Global Parts, you'll find expansion valves perfectly suited to BMW, Audi, Mercedes, Volkswagen, Mini, and more .
• Technical condition – Used valves should be fully functional, free from mechanical damage and corrosion.
• System Type – Make sure the valve you choose is compatible with your vehicle's air conditioning system.

Why choose used expansion valves ?

Used car parts, such as used expansion valves, are an economical solution that allows you to save money while maintaining high quality. By choosing used air conditioning components, you benefit from:

• Lower costs – Used valves are much cheaper than new ones, but offer equally high quality.
• Ecology – Recycling parts supports environmental protection and reduces waste.
• A wide range of products – In our store you will find used expansion valves to the most popular car brands.

How to take care of expansion valves ?

To ensure that expansion valves function reliably for a long time, it is worth following a few rules:

• Regular inspection – Check the condition of the valve during air conditioning system inspections.
• Keep the system clean – Contaminants can interfere with valve operation and reduce air conditioning efficiency.
• Air conditioning servicing – Regular inspections and refrigerant refills support the proper operation of the system.
• Replace on time – Damaged valves should be replaced to avoid problems with the air conditioning operation. If you need a replacement, Global Parts has the right used car parts to ensure the durability and efficiency of your air conditioning system.

FAQ - Frequently asked questions about expansion valves

Question	Answer
What are expansion valves?	These are the components of the air conditioning system responsible for reducing pressure and regulating the flow of refrigerant to the evaporator.
How does an air conditioning expansion valve work?	The valve controls the amount of refrigerant based on temperature and pressure, ensuring stable cooling conditions.
Where is the expansion valve located in a car?	It is most often mounted near the evaporator, in the engine compartment or under the dashboard, depending on the vehicle design.
Does the expansion valve fit every car?	No, it must be adapted to the specific model and version of the air conditioning system, e.g. BMW E60 or Audi A4 B5.
What parts work with the expansion valve?	Air conditioning compressor, evaporator, condenser and high and low pressure lines.
Do expansion valves affect fuel consumption?	Yes, correct refrigerant dosing reduces the load on the compressor and supports the efficient operation of the system.

Summary: Expansion Valves at Global Parts Automotive Store

Expansion valves are essential components of the air conditioning system, ensuring efficient cooling and comfort in the vehicle's cabin. By maintaining their technical condition, you can improve air conditioning performance and avoid costly repairs. The Global Parts automotive store invites you to browse our wide selection of original used car parts . Whether you're looking for car parts for BMW , Audi , Volkswagen , Mercedes, Mini , and more, you'll find them at competitive prices. We strive to ensure every customer finds the right parts for their car, and if you have any questions or concerns about selecting the right components, we're happy to help! Please contact us – we're here to help! For more information and interesting facts, visit our automotive blog .