FLEXIBLE IMMERSION HEATER

A flexible immersion heater assembly which permits fabrication of any desired length heater in the field includes a fluid impermeable flexible tube of non-metallic resilient material containing a section of flexible insulated electrical resistance wire. One end of the tube is telescoped over a frustoconically ribbed nipple on a hose fitting. The other end of the tube is suitably closed by a ribbed plug or a bonded pinch seal. Electrical leads to the resistance wire extend through the hose fitting and sealant means are provided for sealing the leads relative to the fitting. A thermostatic switch or a thermocouple are provided for controlling the heater in response to temperature changes. The heater assembly is adapted to be inserted in pipes, conduits and tanks.