Lochinvar & A.O. Smith 100063648 Flow Switch

The Lochinvar & A.O. Smith 100063648 Flow Switch is a critical safety component engineered for high-performance commercial and residential hydronic systems. This OEM water flow switch serves as a primary protection mechanism, ensuring that the heat exchanger maintains adequate circulation before the burner is permitted to fire. Designed to withstand the rigors of outdoor HVAC installations, it features a robust construction that minimizes friction and provides reliable switching in variable climates. Operating at 120/250VAC with a 10A current rating, this switch effectively prevents dry firing and protects the low-mass heat exchanger from thermal shock or physical damage caused by flow interruptions.

As a direct replacement for legacy part numbers 210176 and 211983-000, the 100063648 is essential for HVAC system protection. It monitors the cooling or heating media and breaks the control circuit immediately if flow rates drop below the designated threshold. Its high-precision paddle mechanism is optimized to reduce nuisance tripping while maintaining sensitive detection, ensuring your boiler safety controls function exactly as specified by the master controller. For technicians servicing Lochinvar Knight or A.O. Smith commercial water heaters, this switch provides the exact electrical and mechanical specifications required for seamless integration into the existing wiring harness.

• System Reliability: Actively prevents burner operation during low-flow conditions, safeguarding the heat exchanger from terminal damage.
• Optimized Compatibility: Genuine Lochinvar flow switch replacement designed specifically for A.O. Smith and Lochinvar hydronic equipment.
• Durable Construction: Engineered for outdoor environments, offering superior resistance to environmental friction and extreme temperature fluctuations.
• High Electrical Capacity: Rated for 120/250VAC at 10A, providing robust switching capability for standard control boards.
• Direct OEM Fit: Replaces multiple legacy part numbers including 210176 and 211983-000 without requiring structural modifications.

What causes a flow switch to fail or trip prematurely?
The most common issues include scale buildup on the paddle mechanism, air pockets trapped in the hydronic piping, or a circulating pump that is failing to meet the minimum required GPM (gallons per minute) to keep the contacts closed.

Can this flow switch be used on both indoor and outdoor units?
Yes, while it is specifically noted for its performance in outdoor switch flow applications, it is fully compatible with indoor boilers and water heaters that require a 10A flow sensing device.

How do I verify if the 100063648 is the correct part for my boiler?
Check your unit’s service manual for the flow switch part number. This component is a standard replacement for many Lochinvar and A.O. Smith series, specifically replacing older numbers like 210176.

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.