Watts 0556008 Valve

The Watts 0556008 is a heavy-duty, 1-inch temperature and pressure relief valve engineered for commercial hot water supply tanks and heater applications. Also identified as the LF40XL-4-150 or LF40XL-150-1, this automatic reseating valve is designed to provide high-capacity protection with an ASME rating of 2,134,000 BTU/hr. It features a 1-inch MNPT inlet and FNPT outlet, specifically configured for high-demand systems that require reliable over-temperature and over-pressure safety measures.

Built with a lead-free copper silicon alloy body, the 0556008 utilizes a 4-inch extension thermostat with a specialized thermo-bonded coating to resist mineral accumulation and ensure accurate thermal response. The valve is set to relief at 150 psi and 210°F, meeting stringent ANSI Z21.22 and CSA requirements. For technicians, the inclusion of tamper-resistant bonnet screws and a dedicated test lever ensures the unit remains secure while allowing for necessary periodic system checks and maintenance.

• High BTU Capacity: Rated for up to 2,134,000 BTU/hr to support large-scale domestic and commercial boilers.
• Technical Precision: Features non-mechanical seat-to-disc alignment for consistent reseating after discharge.
• Durable Construction: The 4-inch coated thermostat probe prevents scaling, maintaining sensitivity in hard water environments.
• Broad Compatibility: Directly replaces and is identical to Watts 40XL-4-150 and LF40XL-150-1 models.

Common Questions

What is the difference between the 40L and 40XL models?
The 40L series typically features a short thermostat for direct tank tapping, while the 40XL series utilizes an extension thermostat, like the 4-inch probe on this 0556008, for installation in the hot water outlet.

Can this valve be used in potable water systems?
Yes, the 0556008 is a lead-free valve, making it compliant with low-lead regulations for potable hot water applications.

Does this unit include a flood sensor?
While compatible with SentryPlus Alert technology, some 0556008 configurations may require an additional activation kit to enable flood detection reporting to building management systems.

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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.