Most techs would then check voltage at the heater terminals, looking for a constant 240 volts during the heating process. 108 degrees indicates the element may not be getting proper voltage or may be defective. If the voltage drops out after a few minutes then move on to the next component in the circuit (hi-limit, i.e.) to find where the voltage is being interrupted. Use the above manual to help you see the components involved in the heat circuit.