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Small white rectangular sensor with wired probe, 14.33 by 12.83 by 9.06 inches

Emerson SQ400C 100dB Wi-Fi water leak sensor

SKU CH-B6HJ-NRCDY MPN SQ400C

Detects water leaks and sounds a 100dB alarm while sending instant app alerts via 2.4GHz Wi-Fi

  • ProtocolWireless
  • SpecificationsWater Detectors & Alarms, PHOVOLT, SQ400C, Wire SQ400C, 2 L
  • Features100 decibels, Water Detectors & Alarms
  • Dimensions14.33in W x 12.83in H x 9.06in D
  • Weight0.01 pounds
  • Package ContentsWater Detectors & Alarms
  • Real-time phone alerts when water is detected via 2.4 GHz Wi-Fi
  • Loud 100 dB alarm audible throughout the home including basement
  • High-sensitivity wired probe detects leaks and flooding early
  • Waterproof probe design suits wet areas near appliances
  • Low-battery warning flashes red and sounds alarm to prompt replacement

Compact leak sensor for home protection

The Emerson SQ400C is a Wi-Fi water leak detector designed for homeowners who want immediate notification of leaks in basements, laundry rooms or near appliances. It connects to a 2.4 GHz network and sends real-time alerts to a smartphone app when its wired probe senses water. The unit sounds a 100dB audible alarm that can be heard throughout the house.

Replaces basic battery alarms

Unlike simple battery-powered buzzers that only alert anyone within earshot, this sensor pushes email and app notifications wherever you are. The upgrade is worth it when you need awareness while away from home or when the risk area is far from living spaces. It is not suited for installations that require 5.0 GHz Wi-Fi compatibility or multiple probe zones from a single unit.

Sustained monitoring with low-battery warning

The sensor uses a power-saving circuit that flashes red and sounds an alert when battery voltage drops, ensuring the device remains operational over long periods. The waterproof probe withstands continuous exposure in damp locations such as near water heaters or dishwashers, while the main body stays dry. The 100dB alarm continues until the leak is cleared or the battery is exhausted.

Highlights

  • Real-time phone alerts when water is detected via 2.4 GHz Wi-Fi
  • Loud 100 dB alarm audible throughout the home including basement
  • High-sensitivity wired probe detects leaks and flooding early
  • Waterproof probe design suits wet areas near appliances
  • Low-battery warning flashes red and sounds alarm to prompt replacement

Specifications

BrandEmerson
ModelSQ400C
ProtocolWireless
Part NumberWire SQ400C
SpecificationsWater Detectors & Alarms, PHOVOLT, SQ400C, Wire SQ400C, 2 L x 2 W x 1 H inches, 0.01 pounds, 1, 100 decibels
Features100 decibels, Water Detectors & Alarms
Dimensions14.33in W x 12.83in H x 9.06in D
Weight0.01 pounds
Package ContentsWater Detectors & Alarms

Questions about this item

What are the exact dimensions of the sensor body so I can check it fits under my appliances?

The sensor body measures 14.33 inches wide by 12.83 inches high by 9.06 inches deep, so verify clearance beneath dishwashers or water heaters before placing it.

How do I connect the sensor to the app and what Wi-Fi band must I use?

Connect the gateway to a 2.4 GHz Wi-Fi network only; the sensor will not pair with 5.0 GHz, then add the device in the app to receive real-time leak alerts.

When and how do I replace the battery in this leak detector?

The low-power circuit flashes a red LED and sounds an alarm when the battery needs changing; open the battery compartment, insert a fresh cell, and the sensor resumes monitoring automatically.

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