Expansion Valves

Expansion valves supply precise amounts refrigerant, ensuring it reaches optimum temperature and pressure.

Expansion Valves

How expansion valves work

To cool the air within an A/C system, the refrigerant needs to reach optimum temperature and pressure. To help it reach this state, expansion valves inject the right amount of liquid refrigerant (mist) into the evaporator. This control over injection helps the evaporator lower the pressure and temperature of the refrigerant efficiently.

Expansion valves also help maintain conditions within the A/C system. They do this by adjusting the quantity of refrigerant injected according to the temperature of the superheated gas at the evaporator outlet. This ensures refrigerant can be converted from a liquid (mist) into a gas efficiently.

DENSO Expansion Valve general image

Features and benefits

  • Precision engineered and built.
  • Efficient and consistent operation.
  • Reduces A/C outlet condensation.
  • Reliable performance time after time.
Precision engineered
We’ve developed and manufactured our expansion valves using our extensive knowhow and practical insight to ensure they offer high performance journey after journey.
Efficient operation
Working as part of the whole A/C system, DENSO expansion valves help the evaporator perform more efficiently.
Reliable performance
Each component in our A/C system is extensively tested to ensure it can withstand the varying temperatures and pressures of repeated operation.

Types and characteristics

To ensure each vehicle’s A/C system performs efficiently, we offer a range of expansion valves.

Expansion Valves types

Box type

Today, the box-type expansion valve is the most commonly used. As the gaseous refrigerant leaves the evaporator and moves through the box-type expansion valve to the compressor, it can internally detect refrigerant temperature to optimize cooling performance.


Our long-standing experience in heat exchange and precision engineering has informed the design and manufacture of our expansion valves.

Fault finding

Any motorist who notices a difference in cooling performance should get their A/C system checked by a professional. Regular maintenance will reduce the risks of costly repairs and ensure trouble-free operation.