Lochinvar & A.O. Smith 100163257 Bypass Assembly

The Lochinvar & A.O. Smith 100163257 Bypass Assembly is a critical OEM component engineered for precise flow management in high-efficiency pool and spa heating systems. Built to withstand the rigorous demands of commercial and residential hydronic applications, this 1/2" NPT bypass kit ensures optimal heat exchanger performance by regulating water velocity and preventing thermal shock. This assembly is a direct replacement part designed specifically for the Lochinvar EnergyRite series, including models ER151-30, ERL152A, and ERN252A. By maintaining the correct pressure differential, the 100163257 water heater part prevents internal condensation and scaling, extending the operational life of the primary heating unit. As a veteran contractor knows, using genuine Lochinvar replacement parts is essential for maintaining system certification and ensuring seamless Bypass Assembly installation. This kit includes the necessary manifold connections and internal valving required to restore factory-spec flow rates without residential-grade compromises.

• Precise Flow Regulation: Maintains consistent water velocity through the heat exchanger to maximize thermal transfer efficiency.
• OEM Compatibility: Guaranteed fit for Lochinvar EnergyRite pool heaters and select A.O. Smith commercial water heating units.
• Corrosion-Resistant Construction: Engineered with industrial-grade materials to survive high-chlorine and varied pH environments typical of pool systems.
• Prevents Thermal Stress: Effectively manages "cold start" conditions, reducing the risk of heat exchanger fatigue and condensation buildup.
• Simplified Serviceability: Standard 1/2" NPT connections allow for straightforward integration into existing copper or CPVC piping runs.

Which heater models use the 100163257 bypass assembly?
This assembly is primarily utilized in the Lochinvar EnergyRite (ER) series, including the ER151, ER202, ER252, ER302, and ER402 models. It is also found in cross-branded A.O. Smith high-efficiency pool heaters.

What are the symptoms of a failing bypass assembly?
Technicians typically observe localized overheating, rattling within the heat exchanger (due to improper flow), or visible leaking at the manifold junctions. If the internal spring or plunger fails, the heater may cycle prematurely due to high-limit trips.

Can this bypass be used with PVC piping?
While the assembly features standard threads, it must be adapted correctly for the specific application. Ensure all high-temperature transitions comply with local mechanical codes, particularly when connecting to pool filtration loops.

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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.