Four Seasons 74647 HVAC Heater Control Valve

Four Seasons 74647 Heater Valve Overview

The Four Seasons Heater Valve 74647 is a cable-operated, non-bypass closed heater control valve built as an OE replacement for select Honda and Acura applications. It uses a plastic body with two hose connectors and a 0.625 in. (15.875 mm) opening for direct-fit HVAC heater circuit service.

Compatible with 1999-2004 Honda Odyssey, 2003-2004 Honda Pilot, and 2001-2002 Acura MDX, this heater valve is a practical choice when the cabin heat circuit needs accurate coolant flow control. The Four Seasons heater valve line focuses on replacement parts for temperature control systems, and part number 74647 follows that OE-style approach.

Key Features

• Cable-operated heater control valve
• Non-bypass, closed-valve design
• Plastic construction
• Two hose connectors
• 0.625 in. / 15.875 mm opening
• OE replacement design

Detailed Description

Four Seasons 74647 is an HVAC heater control valve used to regulate coolant flow through the heater core by cable input from the vehicle’s temperature controls. Its non-bypass configuration and closed-valve operation match applications that require direct heater circuit shutoff rather than bypass routing. This part number 74647 is listed for 1999-2004 Honda Odyssey, 2003-2004 Honda Pilot, and 2001-2002 Acura MDX, making it a focused replacement for common Honda and Acura heater valve service needs.

This part cross-references UAC HV1225C for the same application.

Common Problems This Part Can Address

• Heater output stuck on or stuck off
• Coolant flow not responding to cabin temperature control
• Leaking or cracked heater valve housing
• Restricted heater core coolant flow
• Loss of heat control in the HVAC system

Installation Notes and Tips

Verify hose routing, cable attachment, and connector orientation before installation. Match the 0.625 in. opening and the two-connector layout to the original valve, and confirm the vehicle uses a cable-operated, non-bypass heater valve. After installation, check for coolant leaks and confirm smooth temperature-control operation.

Quality Assurance

Four Seasons 74647 is an OE replacement heater valve built for direct service in the specified Honda and Acura applications. Four Seasons heater valve components are cataloged for HVAC temperature control repair where factory-style fitment and operation are required.