Hydro-Rain Wireless Rain/Freeze Sensor

Hydro-Rain Wireless Rain/Freeze Sensor

Product Files
Product Description

HRC 100 RS RF Wireless Rain Sensor

Hydro-Rain®’s HRC 100 wireless rain or rain/freeze sensor saves water by automatically suspending irrigation watering cycles when it rains or freezes or both!

Features and Benefits

  • Easy No Tools Required - Rain gutter mount bracket is equipped with a tool free bolt system that is both quick and easy to install
  • Adjustable Moisture Activation - 1/8", 1/4", 1/2", 3/4", 1" rainfall settings for variable climates
  • Hygroscopic Discs - Absorb water to activate rain switch
  • Reliable Freeze Sensor Option - Shuts off timer when temperature drops to 37°F, protecting vegetation from the effects of freezing water
  • Universal - For use with most brands of 24 Volt sprinkler timers
  • Constant Communication - Every 30 seconds, (HRC 300/390 models), a signal between the transmitter and receiver for accurate timed water metering. All other timers transmit updated signal every 15 minutes
  • Transmission Range - Over 300 feet line of sight
  • Manual Bypass Control - Allows for deactivation during sprinkler system maintenance
  • Dry Vent - Allows air to be circulated or dampened for fast or slow dry, effectively reducing time for the next watering cycle

Operating Specifications

  • Sensor Type: Industry-standard hygroscopic discs
  • Rain Sensitivity: Adjustable nominal 1⁄8" to 1"
  • Freeze Sensitivity: 37°F +/- 3°F
  • Operating Temperature: 14° F~140° F
  • Housing Material: UV-resistant
  • Receiver Power: 22-28 VAC
  • Transmitter Power: Two CR2032 3V cell, 5-year life


  • Transmitter: Height: 4"
  • Length:  3.15"
  • Receiver: Height: 3.75"
  • Length: 1.1"

Electrical Specifications

  • AC Supply: 24~26VAC
  • Relay Contacts Output: Normal Open and Normal Close 3A@24VAC
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