Hi all,

The other day my friend told me his dryer (early 90's Maytag) was. No longer drying clothes. I told him I'd take a look at it next time I was over. Went over there, sure enough, no heat. We moved it around (nothing major, just scooted it out from the wall) and the we heard a faint buzzing sound, followed by a burning insulation smell. We kept trying to see where it might have been coming from, but couldn't pinpoint it. The dryer didn't start smoking, but the top left of it got extremely hot, to the point it hurt to touch it. We unplugged it, the buzzing stopped, and we set it outside, this way if it did catch, it would be out of the house.
Went back over there today, dismantled the control panel, saw no melted insulation or anything that would lead me to think of overheating. Same for the power wires in the back, as well as the connections to the motor itself. So, with the front off, we plugged it back in. The faint buzzing/humming sound was there again, as well as lots of heat, eventually. The burning smell was back also. What gives? A stuck relay leaving the heating element on, or a shorted heated element? It gets plenty warm now, and would be great for drying clothes if it didn't get so hot.

Any ideas? They can't afford a replacement so I want to help them fix this one if I can.

http://applianceguru.com/

Your problem will be difficult to diagnose without a schematic and component diagram. I don't know where they get hidden in an electric dryer, but I typically find them behind the access panel under the drum, either in front or back. I take it you didn't see one in there when you looked?

I'd be checking the air vent system, including the filter and the
entire air path out. That may or may not be the problem, but
I had occasion last summer to check a dryer and found a wad of
"felt" the size of a large sponge in the lint catcher, and similar
quantities of lint beyond the lint catcher in the ducts of the
dryer itself. Since it was in a (mostly) open porch, it just vented
out the back. Still don't know why it didn't catch fire...

Could be the Maytag is plugged up, and had a thermostatic cutout
to prevent just such a thing.
Just my guess.
Nelson

Ditto that. Clogged lint filters can cause overheating and even fires.

I should have added I blew all the lint out of every orifice with my leaf blower. Found a few bucks in change and some earrings. There is a diagram, but it's in rough shape, I may find another in the unit.

Other than the air vent system (which is now clean as a whistle) what else may it be?

Coincidence, just this week I read on www.automaticwasher.org about the possibility of the heating element coming on when not commanded. But I didn't have that problem, brand or model so I don't remember the cause.

Dryers should be straightforward but they're not. For one thing, half of the same appliance is ground referenced (motors) and half is not (heat). For another, circuit paths get convoluted by attempts to minimize the number of components, leaving possible leakage paths if one component or the harness goes wonky.

The guys over there know appliances like guys here know radios. Pay attention to the main forum definitions, they determine the age range of the appliance. Like here, give them the model number and also the serial number which on most defines the year of manufacture and somebody will likely know the answer off the top of his head.

i just fixed a maytag for a friend that was doing the exact same thing.nothing was plugged in the dryer itself but the vent going out of the house sure was.it wouldn't dry clothes and smelled like plastic burning after i installed a new dryer duct it worked fine.the older ones had a limit switch that turned the heating element off if it overheated but i doubt if the new ones do or at least i doubt if they have the bimetallic switch like they used to but i'm no expert.butchj

Finally! This is a question I can answer! Back in the '70's I used to help with appliance repair and this problem sounds like the heating element has a coil that has broken and sagged enough to touch the metal cover completing a path to ground. Some dryers had power to one end of the heating element at all times and they just controlled the other end to turn off and comtrol the temperature etc. So if the heating element had touched ground somewhere you would have a complete circuit, 110 instead of 220, but would still cause the heater element to get hot whether the thing is running or not.

Heating element(s) that won't shut off - Suspect that it could be a stuck closed thermostatic sensor. Calling for heat regardless of how hot the dryer is inside. Also, if it's not drying when it's hot, that's a sign of no air flow going out to expell the hot damp air. Did you check the dryer vent door outside of the house? Maybe stuck shut with lint build up.

I can assure you it is not a plugged vent problem causing this. How?

After the initial "scare" it sat outside for 3 days. Not plugged in, just sitting on the porch. We brought it back in, and simply plugged it in. We did not hook up the exhaust vent, nor did we turn it on, and it got hotter and hotter over the course of a few minutes. We then turned it on, (still the vent was no hooked up) and it did indeed get hot inside like it should have, but it seemed to get hot very quickly. (Keep in mind, the entire front panel was still off the machine, so I could see if anything was smoking and to isolate where the noise/heat was coming from.

Their initial problem was that it did not get hot enough to dry anything. After moving it, it's always hot.

Where would this thermostatic sensor usually be located on most dryers?

If it gets hot when not turned on it is unlikely that it is a thermostat. Probably a short or less likely a timer problem. Despite common folklore timer failures are not common.
Sandy

I'd recommend checking the heating element Making sure it is not touching anything it shouldn't be touching.

+1 this covers all the symptoms.
No heat.
Buzzing noise.
Hot spot on top.

I agree. I had a Maytag that I had to replace the heating element in where the element was around the circumfrence of the front of the drum where it sucked in air which went through the drum and exhausted out through the rear. When the "halo of heat" broke it was possible to short to the housing (mine didn't happen to do that) and leave the element turned on all of the time (hot top of the dryer when not turned on).

The "halo of heat" was strung through a bunch of ceramic insulators and was easily replaced once the front was removed.

There is no way of knowing for sure if this pertains to the specific model in question, but the only answer is geting into where ever the heating element is and taking a look.

Our current dryer has the heating element in a duct at the bottom of the dryer but it also is strung through ceramic insulators.

Curtis Eickerman

To avoid all problems related to the heating element remove the bottom of the drier then build a firepit out of brick the same size as the drier so that it has something to sit on.

Simply build a fire underneath when ya want to dry ya clothes

thermocouple

As SteveT said, it's probably a heating element coil that has opened up and is shorting against the element enclosure. You're just not listening to him. I had this exact problem during the winter with my 6-year old GE dryer: Plugged in but timer knob in off position. The rear of the top panel was constantly hot, almost too hot to touch. I have no idea how UL allows the coils to be electrically hot while the unit is supposed to be "off", but that's the way it can be. One of my coils had solidly welded its burned tip to the steel pan thus no buzzing or burning smell. In your friend's situation it sounds like the coil is just dangling against the grounded metal pan and arcing. You may be able to open the dryer door and peer through the small holes at the rear of the drum and see the arcing that is causing the buzzing sound.

To get at the heating elements you'll need to:
1. Release and flip up the top panel like a hood on a automobile. There are usually two screws in the top front panel where the door is recessed.
2. Remove the front while lifting the drum slightly, otherwise the drum will fall a fraction of an inch off the friction bearings with a loud boom.
3. Go under the drum and slip the belt off the belt tensioner. (See hints below on this.)
4. Loosen the sides and push them out to create a little more clearance for removing the drum.
5. Lift the drum up a little and bring it toward you. It will fight by dragging and snagging. Don't get rough with it.

You'll see your problem immediately if you inspect the heating coils exposed by removing the drum. There are often a set of two (high and low heat). You'll need to either replace the entire coils & heater pan assembly which is easy, or order a "restring" kit off eBay for $30 and restring the heating elements in your pan. Restringing the coils is not a beginners job. Best bet is to buy a used but tested coil/pan assembly off eBay as the price new from a dealer will pay for half of a new dryer.

While fooling around fixing the dryer the sharp metal edges inside are the biggest threat. They'll cut you in a heartbeat if you don't respect them. When pulling the "FASTON" electrical quick connects to disconnect the thermostat, over-temp switch, and coils, it's better to very gently poke the corner of a small screwdriver into the FASTON to press the little detent out of the way rather than to use brute force to pull the connector off. Some of those appliance connectors require really excessive pull-off force and you can end up with stitches from the sharp sheet metal edges. As the last step of putting the front back on you'll need to lift the drum slightly and set it on the friction bearings that are on the inside of the front panel. Not doing this properly will trash those Teflon friction strips and you'll need to replace them. There will be two or more thin thrust washers on the rear of the drum on the bearing stud. Sometimes one or more stays stuck to the bearing hole. Occasionally one may drop off onto the rear floor of the dryer, especially if you've gotten short-tempered horsing the drum out. Recover them all and their position relative to each other and tie them flat against each other with something like a wire bread wrapper tie or piece of thin solder. Don't apply any "wet" lubricant like oil or grease to anything during reassembly. Just don't.

Do not immediately suspect the thermostat(s). They are much more reliable than people give them credit. It's worth saying again: Do not immediately suspect the thermostat(s). Always suspect another part of the system before the thermostats. Also, you should not need a wiring diagram of the machine, just mechanically disassemble the dryer, find the coil fault, and decide whether to repair or replace the dryer. If you decide to repair it yourself, getting that belt back on the tensioner underneath the drum can be very frustrating for some people, especially days or a week after disassembly when short-term memory has evaporated. Take multiple good pictures of how the belt interacts with the tensioner and motor pulley with a digital camera before you release the belt. You'll be glad you did.

Your friend can't afford a decent used dryer off craigslist? This is a perfect opportunity for you to go find a good used dryer, drag it over to your friend's house then install it for him. Sounds like he needs help, and there you are.

This is a typical new GE pan assembly containing the two heating coils.



This is probably what your coils look like. See how much coil length there is between the white ceramic coil supports? When one of those coil segments burn out, the free ends sometimes make contact with the grounded metal pan containing them. (Looking toward the back of the dryer after drum removal.)








On a residential clothes dryer sold in the US? You mean thermostat, correct?

There is a thermocouple in every electric device from a water heater to a hair dryer to a clothes dryer. They are meant to 'uncouple' the feed if the current gets too high. However they can also fuse and allow current to flow past the rest of the controls. Last winter my landlord had to replace one in my space heater because it would not turn off. I shorted out the one in my hair dryer to make it work. Trust me- there is a thermocouple somewhere. It might not be the problem, but then again it might. Makes more sense than a lose heating element touching the cabinet

Sounds like you know what you're talking about. You've most certainly set me straight on these sorts of things.

Lou