Lochinvar & A.O. Smith 100093870 Door Assembly

The Lochinvar & A.O. Smith 100093870 Door Assembly is a critical replacement manifold door assembly designed for residential gas water heaters featuring the flammable vapor ignition resistant (FVIR) system. This genuine OEM component maintains the combustion chamber seal, ensuring the pilot assembly and burner tube interface correctly with the burner chamber to prevent backdrafting and inefficient combustion. Built for high-heat resilience, the assembly includes the viewport glass, gaskets, and mounting hardware necessary to restore the pressure integrity of the internal combustion environment. Field technicians frequently use this part for water heater repair when the original door threads are stripped or the thermal seal is compromised. Proper installation of the 100093870 burner door is essential for maintaining the correct fuel-to-air ratio and preventing carbon monoxide leakage. Compatible with specific A.O. Smith GCV and GVR series tanks, this assembly ensures the thermocouple and igniter leads are properly routed through verified grommet points.

• Precision Seal Integrity: Re-establishes the 100% airtight seal required for FVIR safety compliance.
• Direct OEM Fit: Eliminates alignment issues common with universal kits during Lochinvar water heater maintenance.
• High-Temperature Durability: Metal-to-gasket construction rated for continuous thermal cycling within gas-fired chambers.
• Comprehensive Kit: Includes the essential mounting components to secure the manifold assembly to the tank jacket.

Common Questions

How do I know if this manifold door assembly fits my water heater?
Verify your model and serial number against the water heater parts list; this unit is typically used in 30, 40, and 50-gallon atmospheric vent gas units.

Does this assembly include the manifold gasket?
Yes, the 100093870 door assembly generally comes with the factory-applied gasket to ensure a combustion-tight seal upon installation.

Can I reuse my old screws with this door assembly?
While the assembly matches factory threading, it is recommended to use the provided hardware to ensure the combustion chamber door achieves even torque and compression.

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.