Relief Valve Discharge Sensor

What’s this Thing that Shipped with my Relief Valve?

If your new Watts Relief Valve just arrived, you’re probably wondering about the sensor that came with it. DON’T THROW IT AWAY! This small piece of technology, when connected, will provide you with advance warnings of boiler discharge, letting you address potential problems before they become safety hazards like flooding or equipment failure.

The sensor remains off and does not transmit data until you’ve activated and connected it via an add-on Connection Kit (sold separately). The addition of the sensor to your relief valve does not change its certification, function, or specification.

Find Your Connection Kit

Stay Aware of Unexpected, Unsafe Equipment Breakdowns

By purchasing your Connection Kit and activating the sensor on your relief valve discharge line, you’ll receive discharge notifications via your Building Management System (BMS), keeping you aware and ahead of boiler and water heater issues and the costly flood damage they can cause.



Building Management

There’s a Better Way to Learn about Boiler and Water Heater Issues

When thermal expansion, or another issue is present, your relief valve can discharge gallons upon gallons of hot water per minute. Unfortunately, you can’t always easily see your relief valve, and if left unchecked, excessive discharge can cause severe damage and pose significant safety risks. Improve your system visibility with real-time discharge alerts, directly from your Building Management System.

Backflow Flood Detection and Protection

Code-Compliant, 24/7 Monitoring

Real-time alerts that satisfy IMC code
Backflow Flood Detection and Protection

Prevent Damage

Catch problems before they become catastrophic loss
Relief Valve Discharge Sensor

Reduce Energy Waste

Avoid the heat and water waste associated with hot water flooding

Add Flood Detection to Any Install

Ready to connect? Your new valve arrives with a connection-capable sensor. This sensor is turned on with the purchase of an add-on Connection Kit. Once you’ve purchased, installed, and activated your Connection Kit, you’ll receive real-time alerts that keep you ahead of flooding and water damage. Have an older-model valve? Make it smart with a Connected Retrofit Kit.

Relief Valve Discharge Sensor

How it Works


Install your Relief Valve and sensor, then find your Connection Kit
Purchase and install your Connection Kit to activate your sensor
Enjoy reliable relief valve monitoring and alerts via your existing BMS utility

Find Your Connection Kit

Frequently Asked Questions

  • Does the relief valve with sensor need a Connection Kit to work?
  • Who do I contact for technical support?

Select Your Connection Kit or Retrofit Connection Kit to Activate your Device

Activated through these add-on Connection Kits, the sensor can trigger the alert system sending notification of flood detection to facility personnel.

Connection Type:BMS
Relief Valve Series:140
LF140
Relief Valve Size:3/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:174A
LF174A
Relief Valve Size:3/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:374A
Relief Valve Size:3/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:40L
LF40L
LFLL40XL
LL40XL
Relief Valve Size:3/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:140
LF140
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:174A
LF174A
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:40L
LF40L
LL40XL
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:N240
LFN240
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:N240
LFN240
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:740
Relief Valve Size:1 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:174A
LF174A
Relief Valve Size:1-1/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:740
Relief Valve Size:1-1/4 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:174A
LF174A
Relief Valve Size:1-1/2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:340
LF340
Relief Valve Size:1-1/2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:342
Relief Valve Size:1-1/2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:740
Relief Valve Size:1-1/2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:174A
LF174A
Relief Valve Size:2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:740
Relief Valve Size:2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor
Connection Type:BMS
Relief Valve Series:740
Relief Valve Size:2-1/2 IN
Kit Includes:Sensor Activation Module with Cable, Ground Wire, Power Adapter, Dielectric Grease, and Flood Sensor

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