GTLH – UNIVERSAL CONTROL WITH A WIDE RANGE OF TEMPERATURES – for domestic and industrial heating applications.

This product is part of CAPILLARY CONTROLS


Oil boiler thermostat. 1-pole bulb and capillary control



  • Available either for temperature regulation or over-temperature protection
  • Factory pre-set fixed temperature, OEM adjustable or end-user knob adjustable temperature
  • Wide variety of temperature ranges customized to requirements
  • Precise temperature control with fast reaction time
  • Adaptable to both air and immersion type applications
  • Multiple bracket options for field retrofit
  • Protective capillary sleeving available



A rise in temperature causes the expansion of liquid within the bulb and capillary.  The liquid acts on a bellows assembly within the plastic housing to open and close electrical contacts.

Technical characteristics
  • GTLH
Type Single pole single throw (SPST), Option : changeover contact (SPDT)
Temperature range -35 to 350°C / -31 to 662°F
Rating 20A - 250V (EN, UL) / 25A - 250V (UL)
Material Copper, stainless steel
Capillary length Up to 3000mm / Up to 118”
Sensing elements diameters 3 to 8mm / 1/8" to 5/16"
Connections Brass or nickel plated fastons, pillar terminals
Approvals CE conformity, ENEC mark according to EN-60730-1, EN 60730-2-9, UL, CAN/CSA, ROHS conformity
Technical drawings