[petersg]

The push to start knob will start the dryer, but it stops when the knob is released. If you hold it in the dryer will continue to run, but it will not heat up.

[PS Staff - Sheila]

The run winding in the motor is opened.

There are two winding in the motor.

The start winding gets the motor running and then the run winding takes over.

Your motor will have to be replace.

These motors are sealed and can not be repaired.

Because the run winding is not engaging the dryer will not heat.

Here is a link to the parts of your dryer model 110.70972990.

Here is the motor.