Lochinvar & A.O. Smith 100208662 Cutoff

The Lochinvar & A.O. Smith 100208662 Probe is a critical safety component designed for low water cutoff (LWCO) systems in high-efficiency boilers and water heaters. As a direct OEM replacement part, it ensures the control board receives accurate conductivity signals to prevent dry firing conditions that can lead to catastrophic heat exchanger failure. This probe is technically identical to and replaces WTR2222 and WTR2222K, providing a seamless fit for technicians servicing Lochinvar Knight and A.O. Smith Legend series units. Engineered with high-sensitivity electrodes, the 100208662 probe maintains electrical continuity through the system’s water; when levels drop below the probe tip, the circuit is broken, triggering an immediate burner shutdown. For veteran contractors, this part is a standard truck-stock item for resolving "no-heat" calls where LWCO sensor fouled by scale or sediment has caused a nuisance lockout. Its robust construction resists the corrosive environments of hydronic loops, ensuring reliable boiler safety control and system longevity without frequent recalibration.

• Direct OEM Compatibility: Engineered specifically for Lochinvar and A.O. Smith systems, ensuring 100% integration with existing LWCO control boards.
• Dry Fire Prevention: Actively monitors water levels to protect expensive heat exchangers from overheating and thermal stress.
• Versatile Replacement: Consolidates inventory by replacing multiple part numbers, including WTR2222, WTR2222K, and 100173718.
• Durable Electrode Design: High-quality materials minimize the accumulation of insulating scale, reducing the frequency of service-related probe cleaning.
• Standard NPT Threading: Features a precision-threaded fitting for a leak-proof seal and straightforward installation in the boiler piping or dedicated LWCO manifold.

Is the 100208662 compatible with both steam and hydronic boilers?
While commonly found in hydronic heating systems, this probe is designed for specific equipment series; always verify your boiler model number against the manufacturer’s parts list to ensure the correct voltage and sensitivity range.

Can I use Teflon tape on the probe threads?
No. Using Teflon tape can insulate the probe from the metal piping, breaking the ground circuit required for the low water cutoff to function. Use a conductive pipe dope (like Megalock) to ensure proper electrical continuity.

How do I troubleshoot a suspected faulty probe?
First, check for scale buildup on the electrode. If the system stays in a "low water" lockout despite adequate levels, clean the probe with fine steel wool. If continuity still fails to register at the control board, the sensor likely requires replacement.

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.