Watts 100XL-8 3/4 Tp Relief Valve 150 Psi 3/4 in

Product Description

The WATTS 100XL-8 3/4 is a temperature and pressure relief valve designed to protect hot water heaters and hot water storage tanks from unsafe temperature and pressure conditions. Rated to 150 psi and 210 degrees F, this valve automatically opens to release excess pressure or heat before dangerous levels are reached. The body is constructed of brass with NPT male inlet and NPT female outlet connections. A test lever allows field verification of valve operation without tools. This model includes an 8-inch extension thermostat element, making it suitable for installations where the tank fitting is recessed or requires a longer probe reach. Licensed plumbers and HVAC service technicians are the primary installers of this valve.

The 100XL-8 3/4 is rated for hot water supply systems up to 105,000 BTU/h. It is used in residential and light commercial water heater installations and hot water storage tank applications where ASME-rated T and P protection is required. The thermostat features a special thermo-bonded coating. Standard pressure settings available include 75, 100, 125, and 150 psi. The 3/4-inch connection size fits the inlet and outlet ports common on residential storage-type water heaters.

Key Features

• Temperature relief set point: 210 degrees F (99 degrees C)
• Pressure relief range: 75 to 150 psi (5.2 to 10.3 bar)
• 8-inch extension thermostat element for deep-well tank fittings
• Brass body with NPT male inlet and NPT female outlet connections
• Unique thermostat with thermo-bonded coating for durability
• Test lever included for in-service operational verification
• ASME rated and CSA listed

Compatibility

Designed for use with water heaters and hot water storage tanks up to 105,000 BTU/h requiring 3/4-inch T and P relief valve protection per ASME and CSA standards.

Installation Notes

Installation must be performed by a licensed plumber in accordance with local plumbing codes and IFGC or IPC requirements as applicable. Shut off the water supply and allow the system to depressurize and cool before removing or replacing any relief valve. The discharge outlet must be piped to a safe drain location per code — never capped or plugged. Verify the replacement valve pressure and temperature ratings match the water heater nameplate before installing.

Technical Specifications

• Series: 100XL
• Connection Size: 3/4 inches
• Inlet Connection: NPT Male
• Outlet Connection: NPT Female
• Pressure Relief Setting: 150 psi
• Pressure Relief Range: 75 to 150 psi
• Temperature Relief Rating: 210 degrees F (99 degrees C)
• Maximum BTU/h Rating: 105,000 BTU/h
• Thermostat Element Length: 8 inches
• Body Material: Brass
• Media: Water
• Application: Water Heater and Hot Water Storage Tank
• Certifications: ASME Rated, CSA Listed
• Warranty: Limited

Standard Information

• Brand: WATTS
• Manufacturer Part Number: 100XL-8 3/4