Weil McLain, 623900133, Baseboard Right Sub Assembly, 6 ft, 9-3/4 in, Cast Iron

Weil-McLain 623-900-133 – 6' Right-End Hydronic Baseboard Subassembly

The Weil-McLain 623-900-133 is a 6-foot right-hand termination panel designed for use with Weil-McLain’s cast iron baseboard heating systems. Engineered for integration into closed-loop hydronic systems, this subassembly provides reliable performance, efficient heat transfer, and robust structural integrity suitable for both new construction and retrofit applications.

Product Application and Function

This right-end panel functions as the final segment in a modular baseboard layout, incorporating integral support legs and connection tappings for seamless termination. Its cast iron body delivers consistent radiant and convection-based heat output, maintaining thermal comfort in high-demand areas such as entryways, perimeter walls, or rooms with large window exposure.

Key Attributes

• Cast Iron Construction – Offers superior durability, corrosion resistance, and thermal retention for long-term system stability.
• EDR Output: Approximates 20.4 sq ft per 6-foot length (based on Weil-McLain ratings), ideal for high-output requirements.
• Integrated Support Legs – Factory-cast feet allow for direct floor placement, eliminating the need for external brackets or wall supports.
• Low-Profile Design – Engineered to minimize space intrusion while maximizing radiant surface area.
• Right-End Configuration – Designed for system termination or as a continuation point for extended runs using coupling kits (sold separately).

Specifications

• Length: 6 feet (Right-Hand Leg Panel)
• Material: Cast Iron
• EDR Output: Approx. 20.4 sq ft
• System Compatibility: Hydronic (hot water and low-pressure steam)
• Connection Size: 1-1/4" NPT tappings

Installation Considerations

This subassembly should be installed by a licensed HVAC or plumbing contractor. It requires proper boiler sizing, system balancing, and alignment with loop return and supply lines. Ensure floor-leveling and surface prep are complete prior to setting the unit. When connecting to adjacent panels, use factory-specified couplings and end caps to maintain structural integrity and prevent leakage.

Professional Use Case

For contractors managing high-efficiency boiler systems or perimeter heating layouts in multi-zone installations, the 623-900-133 provides a reliable, quiet, and maintenance-friendly solution. Its thermal mass allows for slower temperature swings and more even heating across long cycles—ideal for applications where consistent ambient temperature is critical.