A solenoid valve for controlling the flow of hot melt material such as hot melt adhesive. The valve includes an aluminum body in which is disposed a heater cartridge for supplying heat energy to the body. The body is bored to receive an insert constructed of brass of like material having good heat conductivity and the insert defines a cylindric passage. Extending through the cylindric passage is a valve stem that has an outer diameter less than the inner diameter of the cylindrical passage so that an annular flow path is formed. Hot melt material supplied to one end of the annular flow path flows to a valve seat at the other end of the flow path. The diameters of the cylindric passage and the valve stem are established so that the annular path has a sufficiently small radial dimension (e.g. 0.004 inch) that the hot melt material in the path is rapidly and efficiently heated so that when discharged through the valve seat it will be at a suitable operating temperature.A solenoid coil assembly is mounted exterior of the body by a threaded connection between the assembly and the body so that relative rotation therebetween changes the relative axial position of the solenoid assembly and the body. The valve stem is attached to a core within the solenoid assembly so that the stroke of the stem is adjusting the relative rotational position of the body and the solenoid assembly.Rigid with the body is a support housing formed of stainless steel or like low heat conductivity material. The solenoid assembly is attached to the housing so that flow of heat from the body to the solenoid is attenuated by the housing, and the solenoid thus operates at a relatively low temperature.