BBSC – COMBISTAT WITH FAILSAFE LIMITER – for domestic water heating

This product is part of CAPILLARY CONTROLS


Oil boiler thermostat. 1-pole temperature regulation and 2-pole failsafe safety limiter with manual reset.



  • Combined control and safety functions to reduce wiring and mounting costs
  • Independent non self resetting safety
  • Guarantee of safety operation : failsafe capillary
  • Factory pre-set fixed temperature, OEM adjustable or end-user adjustable temperature
  • Changeover contact option on control or safety limiter to pilot signal lamp
  • Available with separate two pole switch



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

Safety limiter with capillary:  The liquid within the capillary is transformed to vapour with an abnormal increase in temperature.  The increase in volume acts on a mechanism to open electrical contacts.  In case of damage to the capillary the fail-safe limiter operates automatically.  The limiter is manually resettable.

Technical characteristics
  • BBSC
Type Single pole single throw (SPST) control with double pole capillary safety limiter
Temperature range 0 to 115°C / 32 to 239°F
Safety limiter temperature Fixed 70 - 125°C / 158 - 257°F
Rating 20A - 240V / 16A - 400V
Material Copper
Capillary length Up to 2500 mm / Up to 98”
Safety limiter capillary Spiralled or single / double / triple bent capillary
Connections Brass or nickel plated fastons, pillar terminals
Approvals CE conformity, ENEC mark according to EN-60730-1, EN 607130-2-9, ROHS conformity
Technical drawings