850 Small

In-Line Design Double Check Valve Assembly Backflow Preventers with Freeze Sensor - Small Diameter

  • Includes a freeze sensor for use with SentryPlus Alert technology to signal facility personnel when temperature nears and reaches the freezing point
  • Compact modular design to facilitate maintenance and in-line repairs with a single access cover
  • In-line serviceable assembly requiring no special tools
  • Two in-line independent positive seating check modules
  • Replaceable seats and seat discs
  • Freeze alerts feature available with add-on connection kit for building management systems (BMS), irrigation management systems (IMS), and Wi-Fi networks

Approval/Certification Information

For product-specific approval information, please refer to the product’s specification sheet (see literature section above) or ask a Watts representative. For general information regarding any approval certification partners identified in the specification sheet, please visit our certification partners’ websites:


ASSE CSA FM Approvals NSF
UL ULC USC WQA