A heater for solvents and flammable fluids having a heater core, an hermetically sealed electrical chamber, and a housing cap. The heater core includes a process fluid tube, a heating element, and a thermal well, all enclosed within a cast aluminum billet. The heating element, the process fluid tube, and the thermal well are all thermally associated with one another. The electrical chamber is embedded in a first end of the cast aluminum billet. Electrodes from the heating element extend into the electrical chamber and are connected to electrical wires. The electrical chamber is filled with a non-conducting epoxy that covers and encloses the electrical connections. The housing cap is sealingly disposed on the first end of the cast aluminum billet covering the electrical chamber.