The Carrier 328963-751 Cap-Stem is a precision-engineered HVAC refrigeration fitting designed for high-pressure service valve assemblies. Constructed from heavy-duty machined brass, this 3/8-inch cap stem ensures a leak-proof seal within the closed-loop system, critical for maintaining proper refrigerant charge levels and preventing atmospheric contamination. As a direct OEM replacement part, it guarantees exact dimensional tolerances required for field service on Carrier, Bryant, and Payne condensing units. Field technicians utilize this flare cap and stem to restore the integrity of service ports where the original components have suffered thread deformation or hex-head rounding. Maintaining a secure HVAC service valve seal is essential to prevent slow refrigerant leaks that lead to compressor overheating and reduced EER ratings. This component is built to withstand the thermal expansion and contraction cycles typical of high-side liquid lines and suction line service valves, providing a reliable mechanical barrier in commercial and residential split systems.

Key Benefits

• OEM Compatibility: Precision-fit for 3/8-inch service valve ports across the Carrier family of brands.
• Brass Durability: Machined from high-grade brass to resist corrosion and handle high torque during installation.
• Leak Mitigation: Provides a metal-to-metal seal to maintain system pressure and prevent refrigerant loss.
• Field Efficiency: Direct factory replacement eliminates the need for universal adapters, reducing service time.

Common Questions

Is this cap-stem compatible with R-410A systems?
Yes, the Carrier 328963-751 is designed to handle the high operating pressures associated with R-410A and R-22 refrigeration cycles in residential and light commercial applications.

What is the thread size for this replacement part?
This is a standard 3/8-inch cap stem designed specifically for Carrier-specific service valve configurations. Verify your service valve port size before ordering.

Can I use this on brands other than Carrier?
While designed for Carrier, Bryant, and Payne equipment, it may fit other HVAC service valves requiring a 3/8-inch brass stem; however, verifying the specific part number in the manufacturer's breakdown is recommended.

Item is Non Cancelable / Non Returnable

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.