Lochinvar & A.O. Smith 100093802 Door Assembly

The Lochinvar & A.O. Smith 100093802 Door Assembly is a specialized natural gas manifold replacement engineered specifically for technical repair of Flammable Vapor Ignition Resistant (FVIR) burner systems. As a critical component in the combustion chamber assembly, this NG manifold door ensures a hermetic seal against the water heater tank, maintaining the integrity of the Flame Guard B-system. The assembly features a resettable door switch (thermal cut-off), which is vital for preventing hazardous operation in the presence of flammable vapors. Designed for precise fitment in Lochinvar and A.O. Smith residential gas water heaters, this OEM manifold door assembly facilitates efficient gas delivery while supporting the structural alignment of the burner and pilot tubing.

Key Benefits

• Enhanced Combustion Safety: Features a built-in resettable thermal switch to protect against flashback and improper combustion chamber temperatures.
• OEM Fitment: Replaces A.O. Smith 9006447005 and Lochinvar 6910803, ensuring exact bolt-on compatibility without field modifications.
• High-Temperature Gasketing: Includes a high-grade manifold door gasket to prevent exhaust leakage and maintain high-efficiency thermal performance.
• System Longevity: Helps resolve water heater pilot light failures and burner ignition issues caused by warped or compromised door seals.

Common Questions

Does this assembly include the gas orifice or burner?
No, this is the manifold door assembly only. It typically includes the metal door, the viewing port glass, the door gasket, and the thermal switch. The burner, orifice, and pilot assembly must be transferred or purchased separately.

When should the manifold door be replaced?
Technicians should replace this part if the door gasket is brittle or torn, if the viewing port is cracked, or if the thermal switch has tripped and cannot be reset due to internal failure. Maintaining a proper seal is mandatory for FVIR compliance.

Is this compatible with LP (Propane) systems?
This specific model (100093802) is engineered for Natural Gas (NG) configurations and is intended for use with Flame Guard B-systems only. Always verify your serial number and fuel type before installation.

This item is not eligible for free shipping.

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.