Samsung Dryer DVE50M7450W/A3 multiple heating issues

Dryer Repair
1

Brand:Samsung
**Model Number:**DVE50M7450W/A3
Main Symptom:Heating Problems
What happens & when:

Error Code (if any):
Parts or tests already tried: Heating Element, Thermal Fuse, Thermal Switch, Thermistor
Photos / video link:

I have been fighting this dryer for some time.
About 2 years after purchasing, it stopped heating. I found the heating element was open and so replaced it. I thought it was a bit early, but whatever….

About 6 months later, the heating element went bad again. Now more suspicious, cleaned the vent from inside house and from the roof, there wasn’t really much lint in it. Put in another element and went on.

About 8 months later, it stopped working again. Now becoming irritated, I took it apart again and surprisingly, the heating element was OK. This time the Thermal Fuse was blown. I put a new one, again cleaned out lint from inside the dryer ducting, around the filter, and in the wall vent too. Again, not much there, but seemed like poor airflow might be the problem, so did it again. Put in a new fuse and it worked for 3 days. Ugh, decided to buy the Samsung OEM thermal fuse for $50 and put that in. That lasted 2-days. I tested the thermal switch with hot air and IR thermometer, it opened and closed as expected. Repeated several times. I ordered a bunch of the cheap fuses and decided to run dryer pulled out from the wall to be sure no vent issue. Ran three loads of clothes through it, so it ran between 2 and 3 hours and the fuse blew again. Put another fuse in, ran the dryer with no clothes in it and pulled out from the wall. I noticed that the exhaust air was hot at first, but then went cold after around 2 minutes. After another 2 minutes or so, it heated up again. Ugh, decided to order a new Thermal Switch even though the old one tested good. I put that in, ran the same test again, same result, the exhaust was hot for a while, then cool for a while, repeat. The 2 minutes of heat followed by a similar time of cold air seemed to be too slow for the thermal switch based on my testing with hot air. When I tested it with hot air, it was more like 15 seconds to go from open to closed, but I tested it in open air, not in the ducting.

I took the thermistor out and measured it. It measures 10K at room-ish temperature so seems OK, but I am ordering a new one of those as well.

Anyone have a theory that fits all these symptoms? Were the two heating element failures unrelated to the blowing of the fuse and the heat coming and going? I didn’t let it run long enough to know if the thermal fuse would blow again with dryer empty and pulled out from the wall, but assume that it would blow again after a while.

Thanks for any help

2

Hello, it sounds like you have had your hands full with this dryer. The thermal fuse opens on high heat, trying to leave the drum. You mentioned a roof vent, which tells me you have venting issues, maybe too long for the dryer to push that amount of hot air out. I know you said you removed the vent, and it still tripped. That leaves an element that is possibly sagging when it gets hot and shorts against the metal housing, the thermistor, or the control board. I would lean toward the element sagging and shorting out. Something is letting the heat get too high. Keep me up tp date, this is an interesting situation.

3

Yeah, I neglected to mention, but I opened up the ducting to inspect the heating element at some point and it seems like it’s in there solidly on the insulators and I don’t think it can move enough to get to any parts of the metal housing. The vent is not a long run, there’s an elbow in the wall and then it goes straight up and out the roof. So 8’ to get up the wall and then around 4’ in the attic to get out the roof. I don’t think the thermistor explains it though, the Thermal Switch should open before the fuse blows otherwise what would be the point of the thermal switch?

4

The science behind this thermal fuse opening is pretty simple. Too much heat, not enough air flow to remove the heat from the frum. The temperature is either getting too hot, or the air flow is not enough to remove it from the drum fast enough.

5

Yes, but the thermal switch should really be opening before the fuse blows. I also measure the resistance of the heating element thinking maybe it was too low, but it was spot on. I checked the fan on the motor thinking maybe it was just slipping on the shaft and not turning, but it’s solid. Everything is perfectly clean now and I put my hand by the exhaust and it is blowing nicely. The thermistor shouldn’t really matter to this, maybe it’s not working and it would mask the problem if it was working, but with no obstruction on the vent, proper heating element, and fan blowing air, the fuse shouldn’t be blowing. It’s quite frustrating as this is not that complicated.