Lochinvar & A.O. Smith 100093983 Pilot/Thermopile

The Lochinvar and A.O. Smith 100093983 Pilot/Thermopile Assembly is a mission-critical ignition component engineered for high-efficiency LP gas water heaters and commercial boilers. This complete assembly is the direct OEM replacement for legacy part numbers 321165-001 and 100078038, ensuring a precise fit and reliable millivolt output within the combustion chamber. Designed for liquid propane applications, this kit includes the thermopile generator, high-temp pilot tubing, and specialized mounting bracketry to maintain proper flame rectification and standby pilot stability. For technicians troubleshooting pilot outage issues or intermittent burner ignition, this 750-millivolt system provides the necessary electrical potential to hold the gas valve electromagnetic coil open without external power. Leveraging stainless steel construction for the pilot head, it resists carbon buildup and thermal fatigue, which are common failure points in commercial HVAC repair and maintenance cycles.

• Universal OEM Compatibility: Direct drop-in replacement for A.O. Smith, Lochinvar, and State Water Heaters using the 100093983 part number.
• Precision LP Orifice: Factory-calibrated for propane fuel recovery to ensure clean combustion and optimal heat transfer.
• Enhanced Thermopile Sensitivity: High-output 750mV generator for consistent gas valve activation and reduced nuisance shutdowns.
• Heavy-Duty Lead Wires: Reinforced insulation to withstand high-temperature environments within the burner tray assembly.

Common Technical Questions

Is the 100093983 compatible with Natural Gas units?
No, this specific assembly is configured with an LP (Liquid Propane) orifice. Using this in a Natural Gas application will result in improper combustion and potential safety hazards.

What symptoms indicate a failing thermopile in a Lochinvar system?
Typical failure signs include the pilot failing to stay lit after releasing the control knob or the main burner failing to ignite despite a healthy pilot flame, often due to the thermopile failing to reach the required millivolt threshold.

Does this kit include the pilot tubing?
Yes, this pilot assembly with tubing includes the pre-bent aluminum line required connect the assembly to the gas control valve.

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.