Screwplug Heaters (CX Series)

Caloritech™ Screwplug heaters are available in four different series. CX Series The Caloritech™ CX Screwplug Immersion Heater is used primarily to heat water in tanks through natural convection currents. Typical heaters have standard 1" - 2 1/2" NPT tapered plugs. Other sizes or plugs are available on special order. All thermostat equipped screwplug heaters with moisture or explosion-proof housings feature a convenient terminal block mounted to a slide out trolley. CXC & CXF Series Caloritech™ CXC Screwplug Heaters are used primarily for water heating applications and feature brass screwplugs with a copper sheath, CXF Screwplug Heaters are used primarily for oil heating applications and feature incoloy® elements silver brazed into a steel screwplug. Low watt density units are used for heavier non-circulated oils, while higher watt density units are suitable for light oils or in forced oil circulation loops. Units are available with optional standard built-in thermostat - a one pole device limited to 240V 25 amp with a range of 50°F to 250°F (10°C to 120°C). 600V thermostats, double pole thermostats and alternative temperature range thermostats are available upon special request. CXI Series Caloritech™ CXI Screwplug Heaters are used primarily for liquid heating applications and are suitable for heating mildly corrosive solutions. They use higher density incoloy® elements welded into a stainless steel screwplug. Units are available with built-in adjustable thermostat and explosion-proof housing (as pictured).


  • Wide range of Watt densities to suit the heating of virtually any liquid
  • Available with general purpose, NEMA 4, NEMA 4X and hazardous area ratings
  • CSA certified for Canada and the United States, UL Recognized. Other optional certifications available such as CE, ATEX, IEC and EAC
  • Available with or without built in thermostats, high limit controls, etc.

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Available with 1" (25 mm) plugs, 1.25" (32 mm) plugs, 2" (51 mm) plugs or 2.5" (64 mm) plugs; additional custom plug sizes and ratings available (check factory for availability); available with up to 135" (3430 mm) immersed length
Available in a variety of standard voltages from 120V to 600V; special voltage ratings available in custom built heaters (check factory for availability)
Optional built-in thermostat well, NEMA 4 terminal housing for outdoor applications and explosion-proof terminal housing for hazardous environments
CE/ATEX approval available for use in Hazardous Locations
EAC available
Optional chemically passivated sheath available for CXI Series only. Chemically passivated sheath providies superior corrosion resistance and longer life in highly corrosive applications