FIXED WTMC3300US/02 Bosch Dryer - Thermal Reset tripping

[SC Tiger]

Model Number

WTMC3300US

Brand

Bosch

Age

More than 10 years

I have a Bosch Nexxxt dryer that is >10 years old but has developed a problem. The thermal reset on the side of the heating element keeps tripping. I reset it last night and used the dryer and it ran two loads, but on the second it tripped the reset again.

I've ordered another reset but do these things actually go bad? Since it will reset and then will get hot I think the element is okay. I tried to clean the lint out of the element the best I could - when I get the new one I plan to do a more thorough cleaning.. The thing that is puzzling me is that it will be okay for one load but the next it goes out, which tells me that it is an issue with either accumulated heat or the reset has gone bad. The exhaust tube is clear - has some lint along the sides but isn't clogged at all.

Could the issue be the temperature sensor that is in the heating vent?

If the element itself is bad I may just replace the dryer. It's getting some age on it and I don't want to have to keep throwing parts at it, but a $40 reset I'm willing to do.

Thanks in advance.

 

[Jake]

Hi,

Are you referring to this thermostat:
00422272 Limiter-Temperature


Yes, they can just wear out after 10 years.

You have to make sure you clear all the lint out of the dryer, they are very sensitive to air flow through the heating element.

Could the issue be the temperature sensor that is in the heating vent?

Do your clothes seem too hot when they come out of the dryer?

I'd start using MEDIUM HEAT instead of HIGH HEAT. I never use HIGH HEAT on my dryer and the clothes come out perfect every time.

Jake

 

[SC Tiger]

That's it. I ordered it and the other thermostat just in case. Mainly because shipping was kinda expensive and I didn't want to pay it twice.

Would a bad/shorted heating element do what I'm seeing (work for one load but trip the thermostat on the next one)? How would that behave?

Plan is to give the heating element a good clean and inspection when I replace the thermostat.

Thanks for your help.

 

[Jake]

If the heating element was grounded it would heat in the AIR FLUFF/NO HEAT cycle.

Try it in AIR FLUFF/NO HEAT cycle and see if it gets hot.

Jake

 

[SC Tiger]

Will try that tonight.

Thank you so much for your help.

 

[Jake]

Ok, sounds good, yes keep us posted.

Jake

 

[SC Tiger]

So far it works fine on lower heat and doesn’t trip the thermostat. This thing doesn’t really have heat settings so much as damp dry, dry, really dry, and burned to a crisp or something. But the lower settings do seem to produce less heat.

Last night I pulled the heater, cleaned it with compressed air and did a ground check. No continuity from the element to the heater housing but continuity from one end to the other. So all good there. Also cleaned out as much dust and lint as I could.

Will put the new high limit thermostat in once I get it just to be safe.

Thanks again for your help.

 

[Jake]

Excellent SC Tiger, glad to hear that.

Thanks for the update!

Jake

 

[Glasterpiece]

If the heating element was grounded it would heat in the AIR FLUFF/NO HEAT cycle.

Try it in AIR FLUFF/NO HEAT cycle and see if it gets hot.

Jake

Mine is heating on air fluff/no heat. I installed a GFCI but it tripped as soon as the dryer switch was rotated to any setting. My meter detects around 1 amp on the ground wire at the breaker box. How do I correct the grounded heating element? Thank you.

 

[Jake]

Do you have the exact same model number WTMC3300US ?

Click here: Appliance Parts

Then you will see a link that says: How to find a model number.

Also, I've never seen or heard of a ELECTRIC 240 volts dryer being connected to a GFCI, a GAS dryer yes because its 120 volts.

Jake

 

[Glasterpiece]

I have model #WTMC3321US/05 Nameplate picture attached.

I'm assuming that a grounded heading element is not normal. I would like to be able to air fluff without heat.

I used a 2 pole 30A GFCI breaker just because I happened to have one lying around.
Thank you.

 

[Jake]

Did you disconnect power to the machine and ohm test the heating element terminals to ground? The metal heating element housing is considered ground.

Here's the heating element for your model:
Heating Element 00436460


And to my knowledge you can't use a GFCI breaker on a 240 volt dryer. You need a normal 30 amp breaker.

Jake