Installation

The flow sensor installation must be performed by a certified professional in accordance with applicable local and national building codes.

The flow sensor is designed to be installed only with NPT valves, and not with PEX valves. It is not compatible with first-generation valves VA4200WZ / VA4201WZ.

Installation with a Water Filtration System

When the home’s water supply does not come from a municipal water system (for example, a private well), it is recommended to install this product after the main water filtration system.

Installing the device downstream of the filter helps reduce the risk of mineral or particle buildup that may be present in untreated water. Over time, these deposits could affect the valve’s ability to fully close when a water leak is detected.

Positioning the device after the filtration system helps maintain the reliability and performance of the water damage protection system.

*To ensure proper operation and product durability, the device must come into contact only with treated water free of impurities.

Technical specifications
Dimensions FS4220:
  • Length: 60 mm (2.36 in)
  • Sensor diameter: ¾ in NPT x ¾ in NPT
Dimensions FS4221:
  • Length: 66 mm (2.60 in)
  • Sensor diameter: 1 in NPT x 1 in NPT
Material:
  • 304 stainless steel, lead-free
Hydraulic pressure resistance:
  • 1.75 MPa (244 PSI)
Certifications and warranty

Complies with ANSI B120.1 standard
Complies with NSF/ANSI 61 standard

Limited 3-year warranty

Included in the Box
  • 1 flow sensor FS4220 or FS4221
  • Installation guide – French version
  • Installation guide – English version

Heads up!

We noticed your cart contains both Zigbee and Wi-Fi devices. These two technologies work differently and are not directly compatible.

  • Wi-Fi devices connect to your home router.
  • Zigbee devices require a Zigbee hub or compatible gateway.

Are you sure this is the setup you want?

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