A cable head for use with coiled tubing electric line in well operations has upper and lower housings attached by a shearable connection to allow release of the lower housing and any downhole equipment carried thereon. A piston is slidable within the housing by fluid pumped through the coil tooling to release a locking mechanism that otherwise prevents the shearing disconnect of the housings. Flow ports in the housing to allow pumping or circulation of fluid through the cable head are positioned to remain continuously open, regardless of the piston position, to maximize the range of flow rates over which fluid can be circulated. The electric line of coiled tubing is only stripped of its armor past sealed receipt thereof in a cable passage below the flow path of the fluid, thereby avoiding exposure of the conductor to the fluid to minimize the potential for damage or failure.