RTS-O & RTS-C Room Temperature Switches

The normally open detector, RTS-O, will close the contact when the temperature drops below 40°F (4,5°C). The normally closed detector, RTS-C, will open the contact when the temperature drops below 40°F (4,5°C). The detector will automatically reset to the normal state when the temperature rises above 40°F (4,5°C).

The RTS Series Room Temperature Sensors are precision engineered, designed and manufactured for commercial or residential use.

Available at factory preset temperature rating of 40° F. Designed to warn of potential sprinkler pipe freezing or other cold detection applications.

Each unit consists of a bi-metal operating mechanism, featuring hermetically sealed precious metal contacts, N.O. or N.C., which automatically reset for repetitive operation, eliminating the need for sensing element replacement.


Unique Features

  • The RTS-O is the only UL, cUL Listed fire alarm / fire sprinkler room temperature switch with normally open contacts.
  • Normally Open or Normally Closed models


Codes and Approvals

  • Required by NFPA 13, 8.16.4 Requiring the protection of all sprinkler piping and valves from freezing
  • Required by NFPA 13, 7.2.5.1 Requiring the protection of the dry pipe valve from freezing
  • Required by NFPA 72, 17.16.5 Requiring a room temperature device to activate if the temperature drops to 40 degrees f


Engineering Specs



VSR Vane Type Waterflow Alarm Switch with Retard:

The Room Temperature Switch shall be a UL and cUL listed device with an epoxy sealed stainless steel case and bi-metallic operating mechanism with silver clad contacts factory set to operate at 40 deg f +/- 5 deg f. The unit shall contain a Normally Open or Normally Closed contact rated for 1 amp at 24 VDC.

Additional information for Engineer:     

  • Can be used to detect a heat source failure and prevent pipes from freezing in any building
  • Can be used with any Listed fire alarm panel, there are no compatibility issues


Installation Tips

  • Mount on a wall in the room near the pipes to be protected. If there is an exterior wall, mount to that wall and away from any heat source. Can be attached directly to a pipe
  • Mount in an area expected to get the coldest.


Additional Information

Click here to view the RTS-O/C datasheet.

For additional questions, contact customer service: sales@pottersignal.com, or tech support: tech@pottersignal.com