Watlow Firerod Cartridge Heaters

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  • Even efficient distribution of heat to sheath
  • High dielectric strength and faster heat-up
  • Incoloy Sheath resists oxidation and corrosion
  • Watlow manufacturing capabilities result in lower internal temperatures
  • UL & CSA Approved lead wires to 480 F and higher
  • All part numbers shown can be modified from stock with different lead wires and lengths
  • Thermal Devices is an authorized Watlow distributor in many geographic territories. In the event that we are not authorized in your area, we will provide a heater of similar form, fit & function to fill your order.


The Watlow FIREROD cartridge heater revolutionized the heating element industry in 1954 when it was patented as the first swaged cartridge heater. The mechanical procedure of swaging reduces the diameter of the heater by compacting the unit. This directly improves the heat transfer and efficiency of the heater. Contact a Thermal Devices’ Sales Engineer for more information! Or, request a quote.

Product Description

Thermal Devices is an authorized Watlow distributor. The Watlow FIREROD cartridge heaters are built using only the finest materials and construction methods and are backed with extensive quality assurance programs. With premium materials and tight manufacturing controls, the FIREROD heater provides superior heat transfer, uniform temperatures, resistance to oxidation and corrosion and a long life even at high temperatures.

FIREDROD Water Immersion Heaters

FIREROD water immersion heaters are ideal for replacing large screw-plug immersion heaters. Because of its compact size the product can be very versatile when designed into a heating system. These water immersion heaters come complete with a brass 3⁄4 inch National Pipe Thread (NPT) double threaded fitting, which allows you to add conduit boxes. Also, FIREROD immersion heaters are sealed at the lead end with a silicone rubber seal. Solid copper leads, with silicone rubber sleeves, are provided for unrestricted wiring. These units are recommended for immersion in water or 90+ percent water soluble solutions.

  • Nickel-chromium resistance wire precisely centered in the unit ensures even, efficient distribution of heat to the sheath


  • MgO insulation compacted to the proper density results in high dielectric strength and contributes to faster heat-up


  • Alloy 800 sheath resists corrosion from water


  • Metallurgically-bonded conductor pins for trouble-free electrical continuity


  • 240 and 480VAC voltage allows flexibility in wiring the heater for use in your particular applications

FIREROD offers many delivery programs to meet all your needs! Contact a Thermal Devices’ Sales Engineer for more information! Or, request a quote.