Four Seasons 74779 HVAC Heater Control Valve

Four Seasons 74779 Heater Valve Overview

Four Seasons 74779 is an OE replacement HVAC heater control valve built for vacuum-operated bypass systems. It uses a plastic body with four hose connectors and 0.625 in. (15.875 mm) openings to match the original heater circuit layout on select Chrysler, Dodge, and Plymouth vehicles.

The Four Seasons Heater Valve line focuses on direct-fit temperature control components for factory-style heater hose routing. This 74779 valve is a vacuum closes bypass heater valve, making it a practical choice when restoring heater flow control on vehicles such as the Chrysler LeBaron and Dodge Shadow.

Key Features

• OE replacement HVAC heater control valve
• Vacuum operation with bypass style design
• Vacuum closes bypass heater valve configuration
• Plastic construction
• Four hose connectors
• 0.625 in. / 15.875 mm hose openings
• Direct replacement for select Chrysler, Dodge, and Plymouth applications

Vehicle Fitment

• Fits 1990-1992 Chrysler LeBaron, Heater Valve
• Fits 1990-1992 Dodge Shadow, Heater Valve
• Fits 1990-1992 Dodge Spirit, Heater Valve
• Fits 1990-1992 Plymouth Acclaim, Heater Valve
• Fits 1990-1991 Plymouth Sundance, Heater Valve
• Fits 1990 Chrysler Daytona, Heater Valve
• Fits 1990 Dodge Daytona, Heater Valve

What This Heater Valve Helps Address

• Heater hose flow that does not respond to vacuum control
• Loss of cabin heat regulation through the HVAC system
• Coolant bypass routing issues at the heater circuit
• Cracked or deteriorated original plastic heater valve housing
• Fitment concerns when replacing the original Four Seasons 74779 valve

Installation Notes

Verify hose diameter, connector count, and vacuum operation before installation. Match the bypass-style layout and confirm the valve orientation against the original part on the vehicle. For best results, inspect heater hoses and vacuum lines for wear before installing the new valve.

Quality Assurance

Four Seasons 74779 is an OE replacement part built to match original heater valve specifications for the listed applications. This part cross-references Hayden 5951 and UAC HV3001C for the same application.