Gates 12309 HVAC Heater Hose - Heater Inlet or Heater To Thermostat

Gates 12309 Molded Heater Hose

The Gates 12309 molded heater hose is an OEM-style coolant hose built for tight engine compartments where a straight hose will not route correctly. It is formed to match factory-style bends and is suitable for coolant, water, and air service, with marine application approval.

Key Features

• Factory-molded heater hose for precise routing in compact engine bays
• EPDM construction for use in heating and cooling system service
• 0.75 in. inside diameter at both ends for consistent hose connection sizing
• 16.54 in. centerline length for factory-style fitment
• OEM-style replacement for heater inlet and heater-to-thermostat routing
• Approved for coolant, water, air, and marine applications

Product Details

Gates Molded Heater Hose part number 12309 is built for vehicles that require a shaped hose to maintain proper routing and clearance around nearby components. The molded EPDM design helps match original equipment hose geometry, making it a practical replacement for heater hose service on the Buick Encore and Chevrolet Trax. This part number 12309 is listed for 2013-2019 Buick Encore heater-to-thermostat applications, 2020-2021 Buick Encore heater inlet applications, and 2013-2021 Chevrolet Trax heater inlet applications.

This part cross-references BBB Industries 13309 for the same application.

Common Uses

• Replacing a cracked or leaking heater hose
• Restoring coolant flow between the heater circuit and thermostat area
• Correcting hose routing in tight engine compartments
• Addressing soft, swollen, or heat-aged EPDM hose material
• Repairing heater inlet hose issues on Buick Encore and Chevrolet Trax models

Installation Notes

Verify hose routing, end diameters, and centerline length before installation. Confirm the hose follows the original molded path without kinks or twist, and inspect adjoining clamps, fittings, and connection points for wear before reassembly. Use the vehicle’s service information to confirm the heater inlet or heater-to-thermostat routing for your specific model year.

Quality Assurance

Gates manufactures this molded heater hose as an OEM-style replacement built to match factory routing requirements for modern compact engine layouts. The hose is approved for coolant, water, air, and marine use.