the heating element is a copper spiral, if it is not damaged (like a light bulb, when it burns out) you should be able to test it with the multimeter for continuity. If there is no continuity, replace the heater tube, if there is you need to know what is the current that must be supplied to it, and then test the rest of the machine with the dummy load of approximately the same resistance similar to that of the heater. Although I am almost sure it is the heater if the rest of the functions are ok.