Four Seasons 39649 A/C Expansion Valve

Four Seasons 39649 Expansion Valve

Four Seasons 39649 is a block-type A/C expansion valve for R134A systems, built with an aluminum body and sealing-washer connections for the liquid and suction lines. It is an OE-style replacement that meets or exceeds OEM requirements and is listed for a wide range of Mercedes-Benz applications, including C300, E350, and GLC300 models.

Key Features

• Brand: Four Seasons Expansion Valve
• Part number: 39649
• Block-type A/C expansion valve for R134A refrigerant
• Aluminum construction with aluminum finish
• Female suction inlet and outlet fittings, No. 12 thread diameter
• Female liquid inlet and outlet fittings, No. 6 and No. 8 thread diameters
• Sealing washer style on suction and liquid connections
• Two mounting holes
• Super heat setting: -4.0
• Style: w/o solenoid
• Meets or exceeds OEM specifications

Product Details

The Four Seasons Expansion Valve line focuses on precise refrigerant metering for automotive HVAC systems. This Four Seasons 39649 valve regulates refrigerant flow through the evaporator circuit to help maintain stable cabin cooling performance in Mercedes-Benz vehicles using R134A. Its block-type design, aluminum construction, and sealing-washer connection style support a direct-service replacement for the original A/C flow restrictor assembly.

Compatible Mercedes-Benz applications include 2019-2023 C300, 2019-2023 C43 AMG, 2023 C63 AMG S, 2020-2023 E350, 2019-2023 E63 AMG S, 2019-2023 GLC300, 2021-2023 GLC300e, and additional C-Class, E-Class, and GLC variants listed in the fitment data. This part cross-references 759870 and 0998300100 for the same application.

Common Issues This Part Can Address

• Inconsistent cabin cooling from improper refrigerant metering
• Warm air from the vents when the A/C system is charged but not regulating correctly
• Erratic evaporator performance caused by a worn or restricted expansion valve
• A/C pressure imbalance in R134A systems
• HVAC performance loss in Mercedes-Benz C300, E350, and GLC300 applications

Installation Notes and Tips

Verify refrigerant type, fitting style, and mounting-hole layout before installation. Replace the valve only after confirming the rest of the A/C system is clean and free of contamination, and evacuate and recharge the system according to factory service procedures. Because this is a block-type valve with sealing-washer connections, proper sealing surface condition and correct torque are important for leak-free operation.

Quality Assurance

Four Seasons lists this expansion valve as meeting or exceeding OEM requirements, making it a direct-fit service part for the specified Mercedes-Benz HVAC applications. Part number 39649 is built for consistent refrigerant control in R134A systems and is backed by Four Seasons product engineering standards.