Maytag Electric Dryer does not heat

[rbm]

My mother who is 91 years old has a Maytag dryer that is not heating up. She lives on a limited income so cannot afford to buy new dryer.I help her financially the best I can.I have done some research on this, but looks like it could be 4 different parts (heater elemnet,fuse,timer,forget the 4th one) and I do not want to replace all possible parts,hoping someone who is an expert can tell me which part is bad to minimize the repair cost, I am some what handy and can  replace part. Anyway the dryer does not heat, on the weekend I was turning the dial to different settings trying to get it to heat and onetime I had it on the top setting for "more dry" and it did heat up, but when I turned the dial again to many different settings I could not get it to heat again, even at the "more dry" setting. Thank you for your help in advance it is greatly appreciated.    

Model pyet244ayw

[JWWebster]

It could be the timer. Take a look at this pic:

INSIDE THE TIMER