Hydro-Rain Wired Rain/Freeze Sensor

Hydro-Rain Wired Rain/Freeze Sensor

Product Files
Product Description

HRC 100 RS Hardwire Rain Sensor

Hydro-Rain®’s HRC 100 hardwire rain sensor is designed to save water and limit damage to foliage by turning off sprinkler systems during rainy or freezing weather. The HRC 100 is easy to install and will provide years of reliable, accurate performance. Constructed of heavy-duty, UV-protected ABS, aluminum mounting bracket, and heavy-jacketed copper wire, the HRS 100 is the right choice for your sprinkler system. No other major brand in the industry makes the thermostat feature standard on every hardwire rain sensor.

Features and Benefits

  • Quick-Set Adjustment - 1/8", 1/4", 1/2", 3/4", 1" Quick-set rainfall settings for variable climates
  • Rain Gutter Mounting Bracket - No tools required for mounting sensor to a rain gutter
  • Rain Off - Variable rainfall settings keep the sprinkler system off during rain storms and then returns the system to automatic mode
  • Freeze Off - Shuts off sprinkler system when temperature drops below 37°F, protecting landscape from effects of freezing water
  • Hygroscopic Discs - Absorb water to activate rain switch
  • Universal - For use with most brands of 24V output sprinkler controllers
  • Heavy-Duty Jacketed Wire - 30 feet of connection wire included and ready for installation
  • Conduit Option - Sensor can easily be mounted to 1/2" conduit (adapter included)
  • Dry Vent - Allows air circulation adjustment for fast or slow dry
  • Three-Year Warranty - Hydro-Rain® ensures full quality performance for the warranty period or they will replace it

Operating Specifications

  • Sensor Type: Industry-standard hygroscopic discs
  • Rain Sensitivity: Adjustable nominal 1⁄8" to 1"
  • Operating Temperature: 14° F~140° F
  • Housing Material: UV-resistant


  • Height: 3½"
  • Length: 4½" (

Electrical Specifications

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


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