Nissens 999241 A/C Expansion Valve

Nissens A/C Expansion Valve for Mercedes-Benz

The Nissens 999241 A/C expansion valve is a block-style HVAC flow restrictor built for Mercedes-Benz applications that use R134A refrigerant. It helps regulate refrigerant flow through the air conditioning system, supporting stable evaporator performance and consistent cabin cooling.

Built from aluminum and supplied with mounting hardware, O-rings, and O-ring seals, this Nissens expansion valve is a direct-fit service part for select Mercedes-Benz CLS550, E350, E550, C350, and related models. Part number 999241 is also cross-referenced to UAC EX529509C for the same application.

Key Features

• Block-style A/C expansion valve for Mercedes-Benz HVAC systems
• Aluminum construction for corrosion resistance and thermal stability
• Designed for R134A refrigerant systems
• Includes mounting hardware, O-rings, and O-ring seals
• Liquid inlet and outlet thread diameter: 0.5500
• Suction inlet thread diameter: 0.7900; suction outlet thread diameter: 0.7500
• OE-style replacement under Nissens part number 999241

Detailed Description

Nissens 999241 is an A/C expansion valve used to meter refrigerant entering the evaporator in compatible Mercedes-Benz climate control systems. By controlling refrigerant flow, it helps maintain proper pressure balance across the HVAC circuit and supports efficient cooling performance. This part is a practical replacement for vehicles such as the Mercedes-Benz E350, E550, CLS550, C300, and GLK350, among others listed in the fitment data.

Nissens develops thermal management components with a focus on aftermarket serviceability and consistent manufacturing standards. The 999241 expansion valve reflects that approach with an aluminum block design and application-specific fittings for R134A systems. If you are replacing a worn or restricted Mercedes-Benz A/C expansion valve, part number 999241 provides a direct service solution for the listed models.

What This Part Helps Address

• Weak or inconsistent cabin cooling
• Improper refrigerant metering at the evaporator
• A/C pressure imbalance caused by a restricted valve
• Temperature fluctuations from a failing HVAC flow restrictor
• Service replacement for leaking or degraded expansion valve seals

Installation Notes and Tips

Verify refrigerant type before installation; this valve is specified for R134A systems. Inspect the mating surfaces, replace damaged seals, and confirm the fitting thread sizes match the vehicle’s original HVAC connections. Proper evacuation and recharge procedures are required after A/C service, and the system should be checked for leaks before returning the vehicle to service.

Fits 2009 Mercedes-Benz E320, N/A. Fits 2009-2017 Mercedes-Benz E550, N/A. Fits 2009-2016 Mercedes-Benz E350, N/A. Fits 2009-2015 Mercedes-Benz E63 AMG, N/A. Fits 2010-2015 Mercedes-Benz GLK350, N/A. Fits 2011-2015 Mercedes-Benz C63 AMG, N/A. Fits 2011-2015 Mercedes-Benz SLS AMG, N/A. Fits 2012-2018 Mercedes-Benz CLS550, N/A. Fits 2012-2014 Mercedes-Benz C300, N/A. Fits 2012-2014 Mercedes-Benz CLS63 AMG, N/A. Fits 2012-2015 Mercedes-Benz C250, N/A. Fits 2012-2015 Mercedes-Benz C350, N/A. Fits 2013-2017 Mercedes-Benz E400, N/A. Fits 2014-2015 Mercedes-Benz GLK250, N/A. Fits 2014-2016 Mercedes-Benz E250, N/A. Fits 2014-2016 Mercedes-Benz E63 AMG S, N/A. Fits 2014-2018 Mercedes-Benz CLS63 AMG S, N/A. Fits 2015-2017 Mercedes-Benz CLS400, N/A. Fits 2016 Mercedes-Benz AMG GT S, N/A.

Quality Assurance

Nissens is a recognized aftermarket manufacturer of thermal and engine efficiency components, and this part is produced to the brand’s stated quality standards. Part number 999241 is built for the listed Mercedes-Benz applications and aligns with the original refrigerant system requirements for those vehicles.