Four Seasons 39026 A/C Expansion Valve

Four Seasons 39026 Expansion Valve Overview

The Four Seasons 39026 expansion valve is a block-type A/C flow restrictor built for R134A systems. It is an aluminum replacement expansion valve that meets or exceeds OEM requirements and is listed for select Nissan and INFINITI applications, including Maxima, Pathfinder, Q45, I35, M45, QX4, I30, and Pathfinder Armada.

Four Seasons Expansion Valve line parts are built for direct HVAC service work, with application-specific inlet and outlet connections and OE-style fitment details. This Four Seasons 39026 valve is a practical choice when servicing an A/C system that needs accurate refrigerant metering and stable evaporator performance.

Key Features

• Part number: 39026
• Brand line: Four Seasons Expansion Valve
• Block-type A/C expansion valve for R134A refrigerant systems
• Aluminum construction and aluminum finish
• Meets or exceeds OEM specifications
• Female suction and liquid connections with O-ring style sealing
• Designed without a solenoid
• Direct-fit HVAC service part for select Nissan and INFINITI vehicles

Detailed Description

The Four Seasons 39026 expansion valve regulates refrigerant flow into the evaporator so the A/C system can maintain proper cooling performance. Its block-type design, aluminum body, and OE-style O-ring connections support service replacement on vehicles using R134A refrigerant. This part number 39026 is listed for 2000-2008 Nissan Maxima, 2002-2004 Nissan Pathfinder, 2004 Nissan Pathfinder Armada, 2000-2001 INFINITI I30, 2002-2006 INFINITI Q45, 2002-2004 INFINITI I35, 2003-2004 INFINITI M45, and 2001-2002 INFINITI QX4 applications.

This part cross-references UAC EX10079C and Pioneer Automotive Industries 759026 for the same application.

What It Helps Address

• Weak or inconsistent cabin cooling
• Improper refrigerant metering at the evaporator
• A/C performance issues caused by a worn expansion valve
• Service replacement needs on R134A HVAC systems
• Leak concerns at aging O-ring style connections

Installation Notes and Tips

Verify the vehicle’s original valve style, refrigerant type, and connection sizes before installation. This block-type valve uses female suction and liquid fittings with O-ring sealing, so matching the inlet and outlet configuration is important for proper fitment. Confirm the application against the vehicle’s HVAC layout for 2000-2008 Nissan Maxima, 2002-2004 Nissan Pathfinder, and the listed INFINITI models before service.

Quality Assurance

Four Seasons lists this expansion valve as meeting or exceeding OEM requirements. The aluminum construction and application-specific design support consistent replacement quality for HVAC repair work on the covered Nissan and INFINITI platforms.