Lochinvar & A.O. Smith 100074221 Holder

The Lochinvar & A.O. Smith 100074221 Rod Holder is a critical OEM component engineered for precise indexing of the igniter rod and flame sensor within the combustion chamber of high-efficiency tankless water heaters. This genuine replacement part ensures the assembly maintains rigid alignment, preventing signal drift or ignition failure caused by vibration or thermal expansion. Designed for compatibility with leading series such as the Takagi T-K3, T-D2, and A.O. Smith ATI/ATO units, the 100074221 provides the necessary mounting geometry for consistent spark gap and flame rectification current. For technicians performing a burner tray teardown or sensor swap, utilizing this OEM rod holder is essential to meet factory specifications and restore reliable firing cycles. Ensure you inspect the associated gaskets and mounting hardware, as proper air-fuel sealing at the holder interface is mandatory to prevent exhaust gas leakage or improper combustion air intake during high-fire operation.

Key Benefits

• Precise Alignment: Maintains the exact factory-specified distance between the flame rod and the burner surface for stable microamp signaling.
• Thermal Stability: Constructed from high-grade materials to withstand extreme combustion temperatures without warping or losing structural integrity.
• OEM Compatibility: Drop-in replacement for tankless water heater parts across A.O. Smith, Lochinvar, and State commercial and residential units.
• System Reliability: Minimizes nuisance fault codes related to ignition failure and flame sensing errors.

Common Questions

What models are compatible with the 100074221?
This part fits a wide range of A.O. Smith and Takagi tankless units, including the T-K4, T-H3, and T-M50 series. Always verify the part number in your specific equipment's service manual.

Do I need to replace the gasket when installing this holder?
Yes, it is standard trade practice to replace the 100074219 rod holder gasket whenever the holder is removed to ensure a gas-tight seal at the combustion chamber.

Can this holder be used for both the igniter and the flame sensor?
The 100074221 is designed to secure both the igniter rod and the flame sensor (ion probe) within the burner assembly, providing a unified mounting point for both electrodes.

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.