THL-L1S Ambient Sensing Thermostat


The THL-L1S is an ambient sensing thermostat for controlling heat trace systems in ordinary and corrosive environments. It is ideal for controlling individual heat trace circuits or switching a contactor coil, energizing entire systems.

  • NEMA 4X Enclosure
  • Temperature Range 15°F to 140°F
  • Factory preset @ 40F
  • Switching: SPDT, 22A, up to 480V

View Data Sheet


  • Pipe Heating
  • – Freeze Protection


  • Tank / Vessel Heating

Technical Resources

Literature: L-130

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Installation: Consult Factory