WATTS® 0066100 100XL Temperature/Pressure Relief Valve, 3/4 in Nominal, 150 psi Pressure, Brass Body, Domestic

WA100XL MFG #: 100XL-4
  • Body Material: Brass
  • Country of Origin: US
  • Domestic/Import: Domestic
  • Manufacturer Name: Watts Water Technologies
  • Media: Water
  • Nominal Size: 3/4 in
  • Pressure Rating: 150 psi
  • Series: 100XL
Series 100XL Temperature and Pressure Relief Valves are used in water heater and hot water storage tank applications to provide automatic temperature and pressure protection to hot water supply tanks and hot water heaters up to 105,000 BTU/hr. They feature a bronze body with NPT male inlet and NPT female outlet connections, unique thermostat with special thermo-bonded coating, and a test lever. Model 100XL-8 is also available with 8 in. (200mm) extension thermostat. Series 100XL is ASME rated and CSA listed. Temperature Relief: 210 deg F (99 deg C), Pressure Relief Range: 75 to 150psi (5.2 to 10.3 bar), Standard Pressure Settings: 75, 100, 125, or 150psi (5.27, 7.03, 8.79, or 10.55 bar).
  • Features and More


  • Required safety device on all water heaters
  • Prevents water heater from blowing up
  • Features a unique thermostat with special thermo-bonded coating
  • Stainless steel spring
  • Thermostat is accurate and proven exclusively designed and manufactured by WATTS®
  • This device is designed for emergency safety relief and shall not be used as an operating control
  • Inquire with governing authorities for local installation requirements
  • Maximum system operating pressure must not exceed 75% of valve set pressure


  • Water Heater and Hot Water Storage Tank


  • ASME Specified
  • CSA Certified
  • PROP65: This product can expose you to chemicals including lead which is known to the State of California to cause cancer and birth defects or other reproductive harm.


  • Limited