My dryer just started acting up. I went thru the forum and did the suggested cleaning out of dust etc. I suspected a thermocouple type thing, the flame detector is failing? It will start the glow coil, then the burner lights up for about 20 seconds(?). Then shuts off. Acts like a flame detector is not detecting a flame and shuts off the gas? Is this correct? I’ll look thru the parts section to see what ‘it’ looks like. How do you check and decide what failed?
Model: Kenmore 110.87873100
SN: MX1873559
Thank you for any help. Would like to fix it because it has been a simple and reliable dryer.
I checked the resistance in the 2 coils as was discussed in a previous posts.
TWO Prong : 1.26K-Ohms
THREE Prong: Terminals 1-2 : 1.399K-Ohms Terminals 1-3: .573 K-Ohms Terminals 2-3: 1.97 K-Ohms
It does light up. But when it goes out, it takes a while for the glow coil to come back on to light the gas. I’ll remove the hose and try it. Just may have a bunch of lint in the hose. I vacuumed out a bunch at the bottom and under the dryer. I’ll post shortly.
Thanks.
I pulled the duct and ran the dryer. I ‘thought’ it may be fixed. The glow coil lit and the flame started. "Seemed’ longer so I turned it off without waitng very long. Then cleaned up the duct. There was a ball of lint in it. Cleaned up the stack as far as I could reach with the brush. No real lint in there. Then cleaned the dryer exit chute in the back with the same brush. Vacuumed and was all set. I trimmed the duct so have less duct work and still stay open and not collapsed. Hooked up the duct. Ran it . And the flame went out after about 80 secs by count.
So to eliminate a possible clog in the vent in the wall, I removed the duct. The same thing happened- the burner was going out very abruptly after 80 secs (by counting). So still have the problem. I notice the flame and it looked strong. There is a little overshoot on the left looking at the glow coild going into the heating duct. But can’t really tell if its overshoot or just the way the flame burns. Looks consistent when it burns but something shuts it off very abruptly. Any suggestions where to look next?
I reread your post to clean out the lint chute by removing the back panel. I’ll do that tomorrow night. But from the front and reaching down with a brush, it was clear.
I have a clamp amp meter. Should I be checking the individual leads coming off the coils?
If the chute is clear, what else do I check? Any help please?
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What did you mean "If it’s clear"? You have to remove it and clean.
Where the vent line goes? If it does go on top of the roof, then it definitely needs a good professional cleaning. If it does go on a side of the house, check the vent outlet.
What did you mean "If it’s clear"? You have to remove it and clean.
Where the vent line goes? If it does go on top of the roof, then it definitely needs a good professional cleaning. If it does go on a side of the house, check the vent outlet.
Gene.
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With the vent hose disconnected, the same thing happens so it is not the vent stack in the house. I’m referring to the dryer itself. I’ll take the back panel off and then clean out the entire venting system IN the Dryer itself. But all signs show that the vent is clear. There is a strong out going air stream from the dryer with the vent hose disconnected. I’m thinking more like a thermocouple type problem or flame detector or some other related checking sensor. I’m looking for a parts lists for the dryer. I’ll be looking at the wiring diagram and searching it. But sure open to suggestions what to check and how to check those sensor items.
Thanks
Lets do one thing at a time. Clean it and give it a try with the vent hose disconnected from the dryer. Put some wet clothes inside and run it for a full cycle.
I removed the back panel. Removed the vent duct hose that was just sitting not connected to the wall vent. Lifted the top cover. Cleaned out this vent chute with a vacuum and brush that goes inside. Cleaned out the blower fan. Found some debris sitting at the lower portion of the chute but of no consequence. This chute on the dryer was fairly clean. Wasn’t really too dirty. Some lint but nothing to cause issues. Result: The burner does the same thing. Vent duct is NOT connected.
The entire cycle is:
1)Set heat. Set it to medium. Turn on dryer.
2) Glow coil starts.
3) Then the gas is ignited and see the flame.
4) Flame on for about 1 to 1-1/2 minutes ( Counted to 80). Turns off. Flame does not turn back on.
Turn off dryer. Repeat. Same thing happens. I’m looking for the thermostat?
I don’t like to guess either. I do not mind the questions.
I waited probably over a minute. But when I turned off the dryer and then tried to start it again after about a 4 minute rest, it started again. Then shut off again. It seems like some temperature hi limit switch turning off the gas valve. Or possibly weak coils as seems to be in many of the cases here? But the resistance measuremant seem ok. Maybe its breaking down when current runs through it? but I do not know.
I’ll be running thru the same checks again tonight.
The heater normally cycles on and off by the temperature inside. Normally the flame should be on at the very first time for about 11/2 to 2 minutes and for about 35 to 45 seconds later. The off time normally is about 3 to 6 minutes. You just did have enough patience to wait.
I’ll try again tonight. So it burns for about 1-1/2 to 2 mins. Turns off then cycles on after about 3 to 6 mins?
I did not understand what the 35 to 45 seconds means. Does it mean the following heating cycles are only 35 to 45 seconds long and then shuts off for a period of 3 to 6 mins?
I’ll run throu it again tonight. It may have been that the initial problem was lint in the vent hose. I cleaned it out and didn’t know that it would cycle in short bursts. Find out tonight and will post if it is working again. Thanks,
I will post if it works for the benefit of everyone .
…So it burns for about 1-1/2 to 2 mins. Turns off then cycles on after about 3 to 6 mins?..
…I did not understand what the 35 to 45 seconds means. Does it mean the following heating cycles are only 35 to 45 seconds long and then shuts off for a period of 3 to 6 mins?..
…It may have been that the initial problem was lint in the vent hose…
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Yes, that’s right.
Restricted air flow is most common cause for such problem. So, it is very possible that the original problem has been fixed.
Looks like that the restricted air flow due to lint was the problem. Cleaning out the lint did solve some of the problem.
Seems that the vent tube is partially blocked because of the way the vent was installed in the house. The vent on the house is at 8" from the floor. The vent on the dryer is 5" from the floor. When the dryer is pushed back with the flexible vent, it collapses the opening some so not a complete circular outlet. I’m thinking the builders installed the vent way too high. Is this possible? I am going to make an adapter box at 3 inch centers that will keep a full open rectangular shape with a circular joint attached to the house. Then a lower circular joint to attach to the dryer with a flex hose so it’s a straight UN-collapsed opening . I am confused why such a height difference between dryer and house. 3 inch off seems alot and it collapses when push the dryer against the wall.
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Another question on how the different setting for drying temperature . Is it simply a longer cycle to keep the flame on for high temperature settings and a shorter cycle for the low temperature?
…Is it simply a longer cycle to keep the flame on for high temperature settings and a shorter cycle for the low temperature?..
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Yes, this is correct. There is the cycling thermostat on the back of the dryer which reads the temperature and controls the electrical circuit for the burner depending on the temperature setting.
In regards of the vent, you can find a lot of information by doing a web search.
The dryer flame is cycling on and off like it is supposed to but it seems to take a long time to dry clothes. How do I check the cycling time and the heat it is supposed to be doing? I ask because maybe I have a bad thermostat or what ever is controlling the length of the drying cycle time. What I mean about too long is that it takes 140 setting on the medium heat (for shirts and blouses) and it did not take that long. I know the exhaust vent is not the problem because I ran without the vent hose connected. What do I check?
I have infrared temp gun for AC work that I could use to check the temperature at the vent tube where the heat enters the dryer. But what temp should it be when it turns off? Is that information available?
Set the dryer at the highest temperature. Disconnect the vent hose from the dryer and measure the temperature by putting a meat thermometer inside the exhaust pipe for about 2"-3". Do not use your infrared temp gun or use as a second device to compare the readings. Do the same thing with the lower setting.