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Major Appliances/o keep dryer thermal fuse from blowing, can I substitute lower temperature thermostat?

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Question
My dryer blows its 220 degree Fahrenheit thermal limiter fuse within a few minutes after I install a new fuse, even with the fabric temperature dial set at medium instead of high.

It's a Frigidaire model FSE747GES1.  However, there seem to be at least two different versions of this model; mine is the version that has a wire connecting one terminal of the high temperature thermostat to terminal R of the timer. (Another version has a timer that has no terminal R, and thus no wire connecting the timer to the high temperature thermostat.)

I'm wondering whether it would be reasonable to replace the high temperature thermostat with a thermostat that will open at a lower temperature.  The thermostat is marked L285-40F, which means it is supposed to open at 285 degrees Fahrenheit, which is hotter than the 220 degrees at which the thermal limiter fuse blows.  For instance, would it make sense to substitute a thermostat that opens at about 250 degrees?  If this makes sense, can you recommend a particular temperature and part number?

If I substitute a thermostat that opens at a temperature lower than 285 degrees, would the only negative side effect be that loads take longer to dry?  Or does the dryer shut down and stay off if the high temperature thermostat opens? (The wire connecting the thermostat to terminal R of the timer makes me wonder whether the dryer will shut down, and if so, whether the drying cycle will automatically resume after the thermostat cools down.)

I've checked typical causes of overheating:
1. The exhaust vent does not appear to be blocked. (The condo building has fans that pull air through the exhaust vent in the wall behind the dryer, and I can feel the pull at the entry to the dryer's exhaust blower if I remove the dryer's front panel to expose the exhaust blower.  The lint trap does collect lint, which means the exhaust blower does pull air through the lint trap.  I empty the lint trap after every load.)
2. The cycling thermostat (which is mounted on the exhaust duct after the exhaust blower) opens when it gets hot, as it's supposed to do. (Unfortunately I'm not sure of the precise temperature at which it opens because I don't have an accurate way to control and measure temperature; it might not be opening at 135 degrees as its L135-15F marking indicates.  If it's failed in a way that causes it to open at a temperature much hotter than 135 degrees, it could explain the overheating and fuse blowing.)
3. The heating coil isn't stuck on, since the fuse didn't blow with the fabric temperature dial set at "air fluff."
4. The back of the dryer is about 8 inches from the wall, which is closer than optimal, but that's how it has operated since it was new. (The design of the condo doesn't permit the dryer to be moved further from the wall, unfortunately.)

Thanks in advance for your assistance!

Answer
Do not modify factory assigned thermostats.   FIND THE PROBLEM....  Remove the dryer vent and place an accurate thermometer in there. The operating thermostat is what cycles the heating element on and off.  All the rest are safety thermostats.  Let me know what the temperature is at the outlet duct.  A partially blocked lint chute area will also cause the thermal safety to blow.....     Let me know if I can help further...     Eric  

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Eric Campion

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We have been repairing appliances for over 36 years and have owned our own business for the same. We can help in any or almost all complaints or at least give you some intelligent input to help you make rational decisions. You can visit our website at http://www.affordableappliance.com

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36 years owning our business and repairing Major Home Appliances.

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Chamber of Commerce. Better Business Bureau. Pottsville Business Association. EXPERIENCE

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36 Years of Working on Major Home Appliances and selling parts. Our office staff is top notched in the Major Home Appliance Service and Part Sales Business

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