BTS5 Fast Response Immersion Temperature Sensor

This is a unique design immersion  temperature sensor with a thin-wall stainless steel tip.  It is a combination of larger industry standard mounting systems with a miniature sensing tip.  This ensures a very fast thermal response with a time constant of typically less than 1 second.

This sensor (also known as a wet pocket sensor) is ideal for use in district heating systems where slower mass sensors can limit the overall system performance.  Also suitable for coolant sensors in new automotive designs, and measuring gas temperature in selected industrial applications.

Available with a push-fit mounting or with a 1/4″BSPG screw-threaded boss.


  • Coolant sensors
  • District heating systems
  • Instant water heaters
  • Compressors


  • Fast response design (Tc ≤ 1s)
  • R25 accuracy of ±0.3°C
  • Interchangeability between sensors
  • Operating range up to +150°C possible
Boiler temperature sensor -fast response design (Tc < 1s)

Technical Specifications

NTC Thermistor Series ET, NT, SP
Temperature Range -50°C/+150°C depending on NTC
Sensor Accuracy R25±3% as standard, ±0.3K (25°C) possible
Sensor Material 316 stainless steel
Connectors Lumberg 2.5 MSF, Tyco Modu, etc