Description
The Watts F556006 LF40XL-4 is a 1-inch lead-free automatic reseating temperature and pressure relief valve engineered for reliable overpressure and overtemperature protection in residential and commercial water heating systems. Designed to meet strict lead-free compliance standards, this valve delivers dependable safety performance while protecting system integrity and occupant safety.
Key Features
- Lead-free construction for compliance with NSF/ANSI 61 and applicable plumbing codes
- Automatic reseating design allows the valve to reseat after activation, minimizing downtime and service calls
- 100 PSI pressure relief rating for robust overpressure protection
- 210°F temperature relief rating for reliable thermal safety cutoff
- 4-inch coated thermostat element for accurate temperature sensing within the water heater tank
- Discharge line flood sensor included for added leak detection and system monitoring
- 1-inch inlet connection for straightforward installation on standard water heater ports
Product Specifications
- SKU: F556006
- Model: LF40XL-4
- Brand: Watts
- Inlet Size: 1 inch
- Pressure Rating: 100 PSI
- Temperature Rating: 210°F
- Thermostat Length: 4 inches (coated)
- Construction: Lead-free
- Valve Type: Automatic Reseating Temperature and Pressure Relief
- Includes: Discharge line flood sensor
Applications
- Residential and light commercial water heaters
- Hydronic heating systems requiring T&P protection
- Potable water systems requiring lead-free components
- Installations where automatic reseating is preferred to reduce maintenance
Why Choose the Watts LF40XL-4?
Watts is a globally recognized leader in flow control and water safety products. The LF40XL-4 combines lead-free materials, automatic reseating convenience, and an integrated flood sensor to deliver a comprehensive safety solution in a single valve assembly. The included discharge line flood sensor provides an additional layer of protection by alerting to any discharge events, helping prevent water damage and supporting proactive maintenance.









