PDA

View Full Version : Thermal limiter


gizmo_529
Jul 13, 2008, 04:57 PM
Hi,. I have replaced the thermal limiter on a Frigidaire crown series dryer four times in the last two years... and one I replaced three days ago has already tripped again... the lint trap is clean and the air flow vent hose is not obstructed... any idea's on what may be happening?. is the coil getting to hot for some reason?? Notice the back of the dryer has a dark yellow discolor from heat... not sure if this is normal... any suggestions would be great... thinking something else needs to be replaced just not sure where to start... Thanks again.

esquire1
Jul 13, 2008, 05:23 PM
Thermal limit blows because of high exhaust temp. If all is clean, is there a kink in the exhaust tubing?

KISS
Jul 13, 2008, 05:43 PM
Exhaust fan motor belt can be skipping due to excess friction.

Credendovidis
Jul 13, 2008, 06:30 PM
Besides what already was suggested : let's go through the list of things to check : what is important is to find out what is causing the overheating :

General test procedures in case of overheating problems :

You have to do a little research here.

Can it be that the drum is frequently overloaded, causing the airflow to decrease, and the dryer to overheat ?

Can it be that the exhaust tube is frequently obstructed? Have you checked the air outflow from the tube?
How is the tube connected to outside?

Can it be that the flint trap is not always cleaned ? Note : ALWAYS clean the air filter from lint before running the next drying cycle.
Lint can cause unnecessary heating up, fire, equipment failure, and it cost money for extra electricity use.

Open up the machine by removing the rear cover.
Plug in the power cord. Close the door (empty drum) and switch the dryer to full power and start the dryer.

Is the drum rotating properly? Is the fan blowing air in one continuous flow?
Is the belt perhaps slipping? Check tension.

Can it be that somewhere in the wiring something is not properly connected and sparking? Or that for whatever reason the heating element is not cooled enough by the air from the blower?

Once you have all checked that you can come back to the board and discuss your findings!
If necessary contact me by private mail (click on my handle and follow instructions) to draw my attention. I will than reply here again.
If this helps solving your problem, than please rate this reply.

Success !

:)

·

gizmo_529
Jul 14, 2008, 06:21 PM
Thanks for the input... I tore the dryer apart and cleaned it out good with a shop vac... there was a good bit of lint in the fan blades... the vent and tube where dirty but not packed... replaced the vent tube... changed the drum belt... was pretty tight but looked a little brittle and sense I had her apart figured I'd change it for $7 and rule that out... put a new thermal limiter in... also found the insulated felt strip that is located at the top of the heater coil was lying on the bottom of the dryer... was held on with staples and ripped off... re installed that... it was pretty dark from the heat on one side... couldnt find a new one so I just flipped it... (other side was clean)... put it all back together and started it... was getting real good exhaust and the drum spun smoothly... ran a load of cloths through... no prob... hopefully the good cleaning and new vent hose was the trick... I'll make a note of cleaning it good once a month besides the lint trap every load... thanks for the input... keep you informed if it fails again.

drtom4444
Mar 27, 2011, 08:48 AM
You have two more t-stats on the air duct in the dryer. These have two different set points to work when the dryer is on automatic to tell when there is no temp difference between the two. One will be near where air is pulled from drum and the other where air goes into drum. They have numbers on them that indicates the temp that they open. What I would do is remove them and mark where they came from. Then you need a toaster oven or regular oven you can set the temp accurately and see if the t-stat opens at the temp specified. My guess is that the higher one is welded closed or just opening too high. Of course, it may be easier to just replace both of them. Make sure your drier is clean in all air passages and the vent is clear. DrTom4444

drtom4444
Mar 27, 2011, 08:51 AM
Cleaning with a shop vac is not going to work to get out deposits that are hardened on like concrete. You have to take the drier apart and scrap out the parts and wash them out. DrTom4444

drtom4444
Mar 27, 2011, 08:54 AM
One other thing: When you clean out the drier make sure you disassemble the pieces and scrape out deposits because if you just vacuum it out it will not get out hardened on deposits. After scraping it out wash out the parts except motor, but vacuum the motor out. DrTom4444