What could be wrong if the dryer will not start?

Clothes Dryer Stops and Starts ' HomeTips

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Apr 23, 2015 - The dryer's heating element works and the motor runs smoothly, But it... and then running the dryer with nothing inside for a few minutes-if it ...

Your issue probably causes by vent duck was blocked either at the rear or from inside the duck. Take off the vent where it hooks up to the rear of the dryer. Turn on the dryer, if it works with hot air again then you have to clean your vent duct. Else, you need a service man to find down what is wrong with the thermostat, burner, etc...

Probably a bad motor. Sometimes you can bring a motor back by lubing it with appliance oil. My phone video of an attempt
If you have the money get another motor. If not then try to lube it is what I would do.

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Check to see if it is properly grounded and that the incoming voltage is correct (120V or 240V) for the wiring config you have.on the dryer as it sits. Also try unplugging and wait a minute or so before plugging back in. This will sometimes reset dryer electrical components to factory settings.

Have you checked the fuse in the plug? Are there any lights on the dryer that should light up but don't? Sometimes wall sockets have fuses too.

Check the exhaust fan at the bottom of the dryer, there is a possibility some my be lodged between the fan wall and the fan blades.

We have been having this same problem. I had tried adjusting everything that I could think of when putting a load of laundry in and got the exact same results as you. I would select the sensor dry and it would count down just like normal until it got to 6 minutes and then it would just run forever at 6 minutes.
My husband and I searched online all this afternoon and came across what seemed way to simple to work. We removed the lint filter, unscrewed the filter housing right inside the door of the dryer, and got to the sensors. We took a damp cloth and wiped them off very well to remove any and all buildup. We wiped everything down very well to remove any built up lint and/or dirt and put everything back in place as was before. We then unplugged the dryer for about a minute and then plugged back in. We put a load of already dry clothes into the dryer and started as usual with the sensor dry. It started out at the usual 41 minutes then skipped down almost immediately to 6 minutes and then a few minutes later I heard the most beautiful sound I have heard in a long time. The Beeper signalling that the timer had counted down to the end and was finished. It had worked. Thankfully. Hope this helps you also.

these dryers have wheel like drum supports and the bronze bearing inside them will wear out causing noise. once you get the drum out, look at the belt idler pulley also it too has a bearing and either one can cause the noise.
if you can get inside the unit, and the bearings dont look worn/wobbly, then you may be able to just lubricate them and it should work for another year or two. if you can get new rollers and idler that would be best and should only cost about 15-20 bucks each.

Here are a few ideas of what might be wrong.. based on your description.. You've bypassed the thermal fuse and the dryer worked however once you removed the bypass, did it work after that? based on your symptom.. it appears that one of the auto-ressting 'overtemp snap switches' may be your problem and may be shutting your system down because it is tripping from excessive heat or it is prematurely tripping because it is defective. I've included a website link that shows assembly drawings and parts breakdown for you to examine but I suspect that you have a bad overtemp switch.. ( I assume that you've cleaned out all lint etc from the vent system both inside and outside the dryer) If you haven't... then you may not get adequate air flow and you truly are getting an overtemp condition.. Good luck.. Here is the link http://www.pcappliancerepair.com/model-display.php

Hope this helps !

the problem might be the start switch itself. if the switch is going bad it could have either a carbon buildup on the contacs preventing it from starting (unlikely) or the contacs are wearing out and it is more hit or miss if it will start. as time goes on the problem will get wose