Watts 0121594 Valve

The Watts 0121594, also identified by model LFN241X-8 125, is a heavy-duty, automatic reseating temperature and pressure relief valve designed for large-scale commercial water heating systems. Featuring a 1.25 inch NPT male inlet and a 1 inch NPT female outlet, this valve is engineered to provide critical safety protection for hot water supply tanks and storage heaters. It is built with a lead-free copper silicon alloy body to comply with strict ANSI Z21.22 listing requirements. The 8-inch stainless steel extension thermostat is thermo-bonded with a specialized coating to resist mineral accumulation, ensuring accurate thermal response even in hard water conditions. Rated for a pressure relief setting of 125 psi and a temperature relief of 210°F, this unit offers a robust CSA temperature steam rating of 3,438,000 BTU/hr. This valve is a direct replacement for the N241X-8-125 and LFN241-8-125-1 1/4, utilizing tamper-resistant bonnet screws and a non-mechanical seat-to-disc alignment for reliable, long-term performance in demanding mechanical rooms.

• Maximum Protection: High-capacity 3,438K BTU steam rating ensures safety for large commercial tanks and water heaters.
• Enhanced Durability: The lead-free copper silicon alloy construction prevents corrosion and meets modern plumbing codes.
• Precise Thermal Response: The 8-inch stainless steel thermostat probe is designed to stay clear of scale buildup, maintaining sensitivity to peak system temperatures.
• Field-Serviceable Design: Includes a standard test lever and automatic reseating functionality to minimize downtime after a relief event.
• Direct Compatibility: Identical to LFN241-8-125-1 1/4 and N241X-8-125, simplifying drop-in replacements for existing piping configurations.

What is the difference between the LFN241X-8 and the standard N241 series?
The "LF" designation indicates lead-free construction using copper silicon alloy, while the "X" denotes the extension thermostat—in this case, an 8-inch probe specifically used when the tank tapping is deeper or when the valve is installed in the hot water outlet pipe.

Is this valve suitable for systems requiring a 150 psi relief setting?
No. This specific 0121594 model is factory-set for 125 psi. For systems designed for 150 psi operation, a different model within the 240 series must be selected to match the MAWP (Maximum Allowable Working Pressure) of the tank.

Can the SentryPlus Alert flood sensor be used with this valve?
Yes, current versions of the LFN241X-8 are compatible with integrated flood sensors. To enable remote monitoring via BMS or cellular gateways, an additional activation kit and sensor module are required.

This item is not eligible for free shipping.

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.