I have a sears dryer 417.90802990 which heats up but will not run..we had this problem before and replaced the themal limiter and it worked fine for about 1 month..same problem..replaced the thermal limiter and it worked for another 4 to 6 weeks..same problem..replaced the thermal limiter again and it works - now 4 to 6 weeks later it is heating but will not run..any idea why the thermal limiter keeps blowing out?

Maybe themal fuse. Make sure all wires are hooked back up right.

bad motor windings, bad cycling , hi limit or themal cut off fuse, bad moister sensor.

Hi. Can you post your model number and I will see if I can help.

Cheers, James.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/james_1fa6cc8df96424be

Check all Thermostats and fuses. Make sure there is 220v going to dryer. Heat circuit also runs through timer and motor.

There are several things that can prevent a dryer from not heating. UNPLUG DRYER BEFORE TESTING ANYTHING.
1- power- Test the receptical to make sure you are getting 220 volts. To do this you need and voltage tester. Both legs should pull 110 and together 220. If one leg is not pulling any power than your breaker is half tripped. Reset breaker to cure your problem. If problem persist it is in the breaker or receptical.
2- cord- To test this unplug dryer. Take the panel covering the cord connections off. Remove cord entirely from dryer. Test each leg for continuity. If any are not showing cont than replace cord.
3- Themal fuse- To test this remove access back access panel on some front panel. By the blower housing there is a fuse white thin sliver or round fuse with 2 wires going to it. The one with 4 wires is your low limit cycling thermistat. The thermal fuse is near that. Disconnect the 2 wires and check fuse for continuity. If meter shows cont fuse it good. If not replace fuse.
4- Hi Limit Thermistat- test same way as thermal fuse. On the heating element housing at the bottom are 3 wires running to a fuse. Test the left and right. The bottom is attached to one of the sides.
5- Thermal Cutoff- Test same way as thermal fuse. This fuse is near the top of the heating elemnt above the Hi Limit. 2 wires with usually plastic covers on them.
6- Heating Element- Below high limit 2 wires. Test for continuity.
If all these fuses are good than you may need to call a technician. The motor may not be getting to the right rpm to activate the senfrigrial switch in the moter. Timer or control board may be out.
7- Motor- If

Sounds like a bad magnetron
From Sears $139.96 Itehttp://www.searspartsdirect.com/partsdirect/part-model/GE-Parts/Microwave-Parts/Model-JVM1653BH01/0432/0123370/G0703233/00001?blt=06&prst=0&shdMod=JVM1653BH01m # 73 on this diagram:

themal fuse if it doesn't start at all, hi limit thermostat if it will

check the element, thermostats, and themal fuse if not heating...

On the side of the heater box is a small black thermal fuse with 2 white wires going to it. If this is open the dryer will not run.Replace it.
Your fuse kit comes with 2 of these fuses and the hi limit.

If you need further help, reach me via phone at https://www.6ya.com/expert/dan_73bbd84fe1d95b61

sound like a motor problem it does not have a resetable limit if it was over heating then it would blow the limit and it would not heat, or the blower limit if it sences overheating would not allow the machine to run at all
get ready for a new motor, or a new dryer
200 plus to replace the motor