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Past history: last yr the flame wld burn for only 5-10 seconds, then shut off. It wld cycle that way every minute or so. Everything else working fine. ALL thermostats, etc. checked fine for continuity.
Not knowing better, I replaced the gas coils, but the Problem persisted. Further research told me to jump (bypass) the high limit thermostat. I did and the flame stayed lighted. So, I then replaced the high limit thermostat - and I was problem free until recently.
Now, I have the exact same scenario!
The flame burns for only 5 seconds and then shuts off. High limit thermostat has continuity. ( I have again replaced it with a new one!!) When I bypass the high limit thermostat, the flame burns endlessly. All else working fine.
Thoughts? And if suggestion is circuit board, is there a way to test to confirm that it is the source of the problem? ( is it possible/likely that my brand new thermostat is bad?)
Many thanks. :) :)
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No circuit board in this dryer. Sounds like an airflow problem or a faulty operating thermostat. The flame should not be on endlessly with hi limit bypassed. The operating thermostat should cycle the burner on/off during the cycle to maintain temperature. The hi limit is a safety device and should never normally cycle off/on. The hi limit thermostat is not designed to cycle and if it does repeatedly, it can cause it to fail.
Eric
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Will investigate and advise. THANKS! Originally Posted by: fairbank56  No circuit board in this dryer. Sounds like an airflow problem or a faulty operating thermostat. The flame should not be on endlessly with hi limit bypassed. The operating thermostat should cycle the burner on/off during the cycle to maintain temperature. The hi limit is a safety device and should never normally cycle off/on. The hi limit thermostat is not designed to cycle and if it does repeatedly, it can cause it to fail.
Eric
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Whelp, here is the update. Replacing the hi limit thermostat and the cycling thermostat did not solve my problem. (and there is NO lint or ventilation problem.)
For clarification, perhaps my stmt that the hi limit thermostat was " cycling" was a poor choice of words. What is happening is that the flame ignites for 10 seconds from cold start (ignites for 5-6 seconds the 2nd or 3rd time around), then cuts out. The drum continues to turn. A few intermittent clicks are heard. After 60-90 seconds, the flame fires up again, burns for 5-6 seconds, then shuts off again. This happens repeatedly (until I get tired of watching it and unplug it).
Thoughts?
I think I will next replace the coils, because that is easy to do, but other than that I am out of ideas. Your assistance is appreciated.
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Eric - you out there?
I have since replaced the gas coils ( in addition to the hi limit thermostat and the cycling thermostat ) but the problem persists.
I'm running out of parts to throw at this sucker.
Any thoughts?
Dan
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My response was based on your statement that bypassing the hi limit thermostat allowed the flame to stay on endlessly. Apparently, that is not the case now? You may have a faulty flame sensor or igniter. When the igniter is powered, it gets very hot and it's resistance goes very low. The heat from it causes the flame sensor to open which kills power to the igniter while simultaneously opening the secondary gas valve. The still hot igniter causes the gas to ignite. Heat from the gas flame should keep the flame sensor open and the resistance of the igniter low, current to the secondary valve coil is through the igniter. If the flame sensor closes again or if the resistance of the igniter goes up or it has an intermittent break in it, the secondary gas valve will close and shut the gas off. This will reapply power to the igniter and the process repeats.
Eric
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Thanks for the quick response.
First I'll confirm that the flame burns endlessly when the hi limit thermostat is bypassed. If not, I will report back. But if so, I will investigate the igniter and/or the flame sensor.
Thanks again.
Dan
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$15 igniter later, problem solved.
Many thanks!!
Dan
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My LDG712 problem is related to Dcarterlaw's, but maybe different.
Dryer heat isn't sufficient to dry clothes. At least, not without running for hours, and maybe not even then. Eventually it will cut off, and may or may not have dried the clothes sufficiently. Small loads obviously work better than large ones. Can't heat a load to remove wrinkles. Not enough heat.
I get a flame, but it looks wimpy; seems like it used to be bigger (6" - 12"), blew past the cone mouth (small end) and made a jet-like sound. Now, it's quiet and looks more like a large candle, about 4" tops; doesn't even reach the cone mouth, and not jetting. And so the dryer doesn't really heat up. It used to heat enough that the cabinet got warm. Not anymore. Cabinet cool to touch, even when dryer has been running a while, with the wimpy flame.
I've cleaned everything, gotten all the lint out (yes, it needed it), made sure the air flows well. Gas source is good; it's jetted for propane, which has worked for decades. Changing tanks doesn't affect it.
I recently replaced the coils and the high-limit switch. Still doing it.
Could the igniter cause this problem, like it did for Dcarterlaw? Or something else? I haven't replaced the igniter (at least not in a long time) or the cycling thermostat yet. Could it be the flame sensor by the igniter?
Oh, and it does cycle. Flame lasts for 15 - 25 seconds, goes out, then re-ignites. Igniter seems to work fine, but maybe its Dcarterlaw's problem manifest differently?
This is a great dryer when it works. Hate to replace it.
Thanks.
Guy
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Originally Posted by: Dcarterlaw Whelp, here is the update. Replacing the hi limit thermostat and the cycling thermostat did not solve my problem. (and there is NO lint or ventilation problem.)
For clarification, perhaps my stmt that the hi limit thermostat was " cycling" was a poor choice of words. What is happening is that the flame ignites for 10 seconds from cold start (ignites for 5-6 seconds the 2nd or 3rd time around), then cuts out. The drum continues to turn. A few intermittent clicks are heard. After 60-90 seconds, the flame fires up again, burns for 5-6 seconds, then shuts off again. This happens repeatedly (until I get tired of watching it and unplug it).
Thoughts?
I think I will next replace the coils, because that is easy to do, but other than that I am out of ideas. Your assistance is appreciated. I just had the same problem with my Maytag dryer it was the coils. The magnets get weak over time and lose connection I replaced them and all better now
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