Watts LFF116 THD B 20-200 LS 1 1/2 Lead-Free Relief Valve, Ductile Iron, NPT

The Watts LFF116 THD B 20-200 LS 1 1/2 is a 1-1/2" lead-free globe-pattern pilot-operated pressure relief / sustaining / backpressure control valve with NPT connections, with a pilot adjustable from 20 to 200 psi. It features a ductile iron body and a buna-n seat. Rated to 200 psi and up to 160°F. This model is certified lead-free for potable-water installations.

This 1 1/2 inch ACV is armed with ArmorTek®, a patented 3-part advanced epoxy coating system designed to limit both microbial induced (MIC) and exposed metal substrate corrosion. This pressure relief control valve is designed to permit flow when upstream pressure is above the adjustable setpoint of the control pilot, and throttle toward closed when upstream pressure falls below the adjustable setpoint. When the valve is installed off the main line on the branch of a tee, it serves as a pressure relief control valve. It is normally closed and quickly opens when upstream pressure exceeds the pilot setting, relieving excess pressure. This Classic valve style has a globe body pattern with threaded end connections, pilot adjustment range of 20-200 psi, configured with Buna elastomers, and limit switch. SentryPlus Alert® technology provides intelligent pressure monitoring and notifications using integrated sensors, and integrates with the Sensor Control Monitor to deliver maintenance alerts through BAS via RS-485 Modbus or the Nexa® platform over Wi-Fi.

Features

• Body construction with patented 3-part ArmorTek epoxy coating for advanced corrosion resistance
• Globe body pattern with threaded end connections
• Pilot adjustment range 20-200 psi
• Integrates with the Sensor Control Monitor to deliver maintenance alerts to BAS via RS-485 Modbus or the Nexa platform by Wi-Fi connectivity
• Body and cover are constructed of strong and durable ductile iron (ASTM A536)
• Includes limit switch

Common Questions

What pressure setpoint can this valve be adjusted to?

The pilot on this valve is spring-ranged for 20–200 psi, so your target setpoint must fall inside that band. Watts builds the 115/116 platform with several pilot springs (2-30, 10-75, 20-175, 20-200 and 30-300 psi); ordering a setpoint outside 20–200 psi means a different pilot, not a field adjustment.

What is the maximum working pressure?

This unit is built as THD (NPT Threaded) and is rated to 200 psi. Threaded and grooved bodies on this platform carry a higher working pressure than 150# flanged bodies, so do not assume a flanged datasheet applies here.

What fluid temperature can the Buna-N trim handle?

This valve is built with Buna-N elastomers, good to about 160°F. Watts offers the same body with Buna-N (to 160°F), FKM/Viton (to 250°F) or EPDM (to 300°F) — pick the elastomer for your fluid temperature, not the body.

Is this valve certified lead-free for potable water?

Yes. The "LF" prefix denotes Watts lead-free construction, compliant with the weighted-average 0.25% lead requirement of the Safe Drinking Water Act (NSF/ANSI 372) for potable-water service.

Specifications

• Type: Relief
• Size: 1-1/2"
• Inlet Size: 1-1/2"
• Outlet Size: 1-1/2"
• Connection: NPT
• Body Material: Ductile Iron
• Seat / Seal Material: Buna-N
• Max Pressure (psi): 200
• Operation: Pilot-Operated Diaphragm
• Port Style: Full
• Country of Origin: United States
• Warranty: 1 Year Limited
• MPN: LFF116 THD B 20-200 LS 1 1/2
• Temperature: up to 160°F
• Lead-Free: Yes
• Item Type: Valve
• Control Function: Pressure Relief / Sustaining / Backpressure
• Valve Platform: Classic (F-Series)
• Body Pattern: Globe
• Pilot Adjustment Range (psi): 20-200
• End Connection / Pressure Class: THD (NPT Threaded)
• Configured Options: Limit Switch;Strainer
• Coating: ArmorTek 3-Part Epoxy