Customer Questions and Answers for Heater-Spiral by Bosch

Marianne, You will want to test the thermostats and thermal fuses on the unit. If there is continuity on them then they are good. If not then replace necessary part. IF these checks ok then There are 2 components other than the thermostats which would cause the heating element not to work. First is the motor and second the Control board. The best option is to disconnect the power to the unit and access the heating element. Disconnect one wire that is going to the heating element, preferably the one on the thermostat side. Plug the unit back up and using a multimeter you will want to turn the dryer on and test for 120 vac at the terminal on the heater where the wire was disconnected. What this will do is eliminate the heater element itself and the motor. If there is 120 vac at this point then you know the heater is good and the motor is good because the other 120 vac coming through the thermostats is the control board side of the circuit. If there is not 120 vac at that point then you will want to test the other terminal on the heater and check for 120 vac. If there is not 120 vac then the motor would be bad .