Add-on sensors for our HVAC Smart Relay Switch (HSRS), RF wireless model, 2nd generation. For installations where traditional wire runs are not possible or simply inconvenient. Sold as a set of two (2). Available sensor models are shown below:


RF Range 100 ft.
Battery AAA (x2)
Dimensions 3.25″ x 1.5″ x 0.5″
Wired input
Mounting tape+screws


  • GEN2 – Our second generation “classic” sensor yields an effective wireless range of 100 ft. Requiring two (2) AAA batteries (not included), they are auto-addressable (up to 65,000+ possible IDs) and measure 3.25″ x 1.5″ x 0.5″. Foam mounting tape and screws are supplied. (GEN2 sensors do not store a permanent address and therefore must be initialized and re-registered whenever batteries are replaced.
  • Notes:
    • We currently offer two available wireless product models: 2nd generation and 3rd generation. The two product generations are not cross-compatible as they operate on different radio frequencies. Therefore, a 2nd generation controller will not accept a 3rd generation sensor. Nor will a 3rd generation controller recognize a 2nd generation sensor.
    • The G2-classic sensor provides wired contact screw terminals for optional external wired switch (N/C) or closed contact loop. Unless you plan to utilize this input, it must be disabled to avoid inadvertent trigger. To disable, simply apply a short jumper wire across the wiring terminals.
    • RF range values are based on ideal conditions in open space. Actual results will vary for every installation. In general, wireless signals can be diminished or impeded by RF interference, concrete walls, large appliances, etc.



  • Expandable (up to 8 wireless sensors)
  • Compatible with HSRS system (wireless model)
  • Battery-operated
  • Simple mounting



What’s Included:

  • Door/window transmitters (qty 2)
  • Magnets (qty 2)
  • Double-sided foam tape
  • Screws


  • The G2-Classic sensor requires two (2) AAA batteries, not included.


Tech Sheet:

Classic (GEN2)


Additional Info:



Ask a Question:

Weight 1 lbs
Door/window sensor

Wireless classic (GEN2), Wireless mini (GEN3), Wireless basic (GEN3)