FIXED WGD92HEFC Whirlpool dryer "check vent" light & moister sensing issues

Jake

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Once the dryer reached 110-120 I heard a "click", the flame went out, and the temps started dropping.
Was the dryer pulled out from the wall and Did you have the exhaust vent still off the back of the dryer when the flame cut-off so soon like that?

I really don't think its a CCU problem, something is telling the flame to cut off way too early. If the dryer is pulled out from the wall and the exhaust hose is off and no clothes are in the drum, and you have it on TIMED DRY that flame should stay on till it gets about 180 degrees on high heat.

This dryer is on natural gas or propane?

Jake
 

MxRacer965

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Darn, forgot to add those details...

Yes, still pulled out from the wall with the exhaust vent removed.

Dryer is on natural gas.

And you are correct in that the dryer was pulled from the wall, no exhaust vent, timed dry, heat set to high, no clothing inside.

I can order up an outlet thermistor if that makes sense even though it checks out as good at room temp...could it be the resistance is dropping to low too fast when it gets hot, causing the CCU to think outlet temps are higher than they actually are and shutting off? Could that also be why the “check vent” light had illuminated frequently in the past? Theoretically if the vent were clogged that would lead to abnormally high temperatures I assume, and if the thermistor isn’t functioning correctly it could erroneously be causing the CCU to believe the vent was clogged.
 

Jake

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Ok,

I located your tech. data sheet here: https://drive.google.com/open?id=16ehM0MatLGyAtfOrNoyHid9MrMT3FBJe

There is something interesting I found in it that I've not seen before on Whirlpool Dryers, Read page 20 where it says: TEST #5a: Adjusting Customer-Focused Dryness Level

You can try to increase the drying time up to 30%.

Also page 17 TEST #4a: Thermistors

Did you disconnect the thermistors before ohm testing them? Then look on page 10, it gives you a heat test to run. Your thermistors seem in range per the chart listed there.

High Heat is lower on this model at 155 degrees, that gas flame shuts off at 155 degrees and should cycle back on at 10 to 15 degrees below 155 degrees which would be at 140 to 145 degrees the gas flame heat should cycle back on.

Jake
 

MxRacer965

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Jake,

I found the manual under the CCU a couple weeks ago so I have been following it and I noticed the same thing you did on page 20 but I haven't tried adjusting the dryness level since I never changed it from the factory default the dryer came with. I can certainly check it when I get home on Thursday (away on business at the moment). I assume it will check out fine though and that it wouldn't cause the dryer to say there is 10 minutes remaining and then have it jump to 50 minutes remaining on the "normal" setting though would it?

As for test 4a I did exactly as it instructs; I pulled the P14 connector off of the CCU and took my readings for the inlet and outlet thermistors there on P14. I did not remove the connectors at the thermistors, and I did not check resistance at the thermistors directly, only from connector P14 that plugs into the CCU. I checked the resistance between R/W for the outlet thermistor (14-3 and 14-6), and the resistance between R (14-1 and 14-2). The values were within the spec in the manual and as you advised. There is no short per step 4 in test 4a.

I did notice the 155 temperature as you mentioned, but I also took note that the instructions are to take the reading at the exhaust and not in the dryer itself. I figured the temp inside the dryer would be higher than at the exhaust? Regardless right now it isn't getting above 110-120 inside the dryer before it cuts off and drops to as low as 80 before turning back on.

I must say I am certainly learning quite a bit and I appreciate the continued assistance! Just wish it was a little less of a conundrum than what it has turned out to be...

I have an outlet thermistor on order...guess I'll try that next. I may just order the rest of the various sensors (high limit thermostat, thermal cut off, flame sensor, etc) and replace them one at a time and if none of them solve it I'll pull the trigger on a CCU unless you have any other ideas? I did notice that test 4a ultimately states to replace the CCU if the thermistor checks out and the problem remains...wonder if replacing the other components would just be a waste of time and money. What are your thoughts?
 

Jake

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Ok,

Well it can only be two parts causing this problem now if the thermistors are good, the CCU or the Gas valve assembly itself.

Here's the gas valve assembly for your model:
Gas Valve Assembly 280119


This is extremely rare to ever see this happen on a Whirlpool dryer, 99% of the time its the gas coils that go bad when this problem happens, and your saying you hear the gas coils clicking but no gas coming out while the ignitor is glowing red?

Jake
 

MxRacer965

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Within moments of the igniter coming on I see a strong flame ignite and burn until I hear a click and it shuts off around 110-120 degrees. So sounds like it’s the CCU?
 

Jake

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Lets bypass your hi-limit thermostat first and see if the flame stays on longer and cycles on and off normally.

I want to make sure its not cycling on the hi-limit thermostat. Its located on your burner tube.

Here's the hi-limit thermostat for your model:
High Limit Thermostat WP3391912


Unplug the dryer first, then remove the wires from the high-limit thermostat and use black electrical tape and tape those two wires together, don't cut the wires. Then try the dryer with no clothes in it.

When you are testing the dryer, all the access panels are on and in place? Your not leaving any panels off?

Jake
 

MxRacer965

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No problem, I’ll test tomorrow or Friday and report back.

All panels have been installed during my testing for temperatures and testing duration the gas is on.
 

MxRacer965

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OK...the saga continues...

Disassembled again and decided since I was already there I would do test 4c on page 19. Thermal cut off was fine, it had continuity. Just for the hell of it I also checked the high limit thermostat and it had continuity (though nothing in the manual states that is a valid test so not sure if that means anything or not).

I then disconnected the wires on the high limit thermostat, taped them up, and assembled the dryer. Started it on timed dry and the Igniter never came on, and no flame at all with the high limit disconnected.

Took it apart again and reconnected the high limit thermostat, and I also took the wires off the outlet thermistor and checked continuity there just for the hell of it. Checked out fine.

Assembled again and started the dryer on timed dry. Igniter came on, flame came on. Dryer heated to 170 then cycled off. Reached 110 and cycled back on. Reached 170, cycle off...cycle on at 110 and reached 180...repeated exactly this way for the next half hour until I shut it off.

I did a little cleaning with vacuum cleaner while I was in the area as well since there was some lint residue in there by the high limit thermostat, etc. previously my focus was on the exhaust ducting.

Going to try a couple loads tomorrow since it seems to be reaching the right operating temp on the high end...

Anything else to check out?

Edit: I just realized you may have intended for me to directly connect the two wires from the high limit together to ensure constant continuity regardless of the temperature. I just took them off and taped the ends so they couldn’t touch anything, including each other. I suspect I botched that test didn’t I?
 
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Jake

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Edit: I just realized you may have intended for me to directly connect the two wires from the high limit together to ensure constant continuity regardless of the temperature. I just took them off and taped the ends so they couldn’t touch anything, including each other. I suspect I botched that test didn’t I?
LOL, yes, those hi-limit thermostat wire are suppose to be tapped together, not taped separately. I was wondering why it would not heat at all after you said you did bypass it, but you didn't bypass with the wires separate from each other.:)

WOW, it seems you did something to make it start cycling properly, Yes, do some loads and let us know what happens.:)

Jake
 

MxRacer965

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OK, ran a load on “normal” last night and the check vent light illuminated almost immediately. Exhaust is still disconnected. It took over an hour to dry but it did dry. It should take about 40 on that mode I believe.

we put a load in last night and ran it for 40 minutes on timed dry and it was still wet this morning. I started the load again on timed dry. I’m watching the flame and it comes on for 13 seconds and turns off for a minute! No wonder it isn’t drying...and that’s with it set to “high” temp.

Hopefully this helps tell something?
 

Jake

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The exhaust is blowing lots of air out the back of the dryer?

Bypass the high-limit thermostat and use black electrical tape and tape those two wires together, don't cut the wires.

Jake
 

MxRacer965

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Air is blowing out the back...and that last test I think was not useful. I didn't realize my wife had ran the thing multiple times to dry a load and never cleaned the lint trap. So the 13 second on time was probably due to that; it was pretty clogged up.



I didn't have a chance to connect the high limit wires together to bypass the thermostat and I'm heading out of town again tomorrow and Wednesday but my wife HAD to get some clothes done so I at least observed the operation. Here is what I found:

This video is of the dryer completely empty as I did a temperature test and is of the flame from the inspection hole. I noticed the flame is traveling outwards mostly and looks pretty healthy.

Here is the video with no load:


I put a SMALL/partial load in and ran the dryer. It did fine on timed dry, clothes came out HOT and dry. The first time the flame started up it ran for nearly 7 minutes before shutting off.

I put the rest of the load in that my wife wanted ran and observed the flame again. Looked a little "lazier" than before with some of the flame trending upwards instead of out.

Here is the video with a heavier load:


The load in question was this:


I noticed a couple times it would ignite and shut off relatively quickly, less than 45 seconds with the heavier load. I got to wondering if the air flow decrease due to the extra clothing and thus the "lazier" flame was tripping the high limit thermostat, and I noticed ALL the clothes were piling up on the front of the dryer where the outlet/lint trap is. The dryer was level with maybe a slight tendency to tilt forward. Got to wondering if the constant barrage of clothes against the front door and the outlet were just enough to drop the air flow and cause a problem...so I lowered the back and raised the front...a LOT. Like a full bubble+ on a level off so the front was super high. This caused all the clothing to stay pretty much centered in the drum with some still falling over the outlet. Flame would also stay on for 1 minute + in many cases like that (sometimes 2+), and the load from the picture dried in 40 minutes on timed dry with no issue.

So...does this tell anything? Obviously I would expect a drop in air flow with clothing inside, but is it really THAT sensitive? It hasn't been for 3 years! Should I assume that this slight drop in air flow is causing more heat to reach the high limit thermostat (due to the "lazier" flame and heat going up instead of outwards) and it is actually malfunctioning and cutting gas supply early as a result?

When I get back hopefully there will be some more clothes to run and I can eliminate the high limit thermostat unless you think it is prudent to replace it given the observations above.
 

Jake

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I'm out in here in rural Western Arizona, where the internet here sucks and is too slow to download all those video files, it would be best to upload the videos to Youtube and post the Youtube link here. Or share your videos per Google Drive, Dropbox, or Microsoft OneDrive and post the share link here.

A lazy flame means you have a vent restriction, if the flame is lazy with no exhaust duct on, then you'll need to check/clean the inside of your air ducts.

Jake
 

MxRacer965

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Sorry, here are links on google drive.

The flame isn’t lazy to me per se...just noticed it has a tendency to go upward ever so slightly instead of entirely outward when there is a load in. I thought this could be due to reduced air flow with a load in and I could improve it by getting the clothing away from the front of the dryer where the lint trap is (which I did by tilting the dryer heavily). My thought was that if the high limit thermostat is marginal that extra tendency to emit flames upward could trigger it too soon. Obviously no idea if that theory is right but thought I’d post and get feedback.

Anyway, here is the flame with nothing in the dryer.


Here is the flame with the dryer level with a load in it.


The ducts inside the dryer are clean with no obstructions, and the vent is removed.
 

Jake

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Have you cleaned out your lint duct #45 here:

Because per your last video with a load it is lazy and cycling the flame off on the high-limit thermostat, that's why the flame is cutting off prematurely.

Jake
 

MxRacer965

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Everything is “clean”. Just some dust/dirt/lint from any dryer that is used. No build ups or blockages.

Looking into the vent from the back. Just a string and a couple blotches of lint that broke free when I was cleaning.
C72B3F5E-EE84-4D6B-A16A-E9DEA2753F78.jpeg


Motor looking into the vent, you can see thermistor and fuse.

162BA572-8FED-42D2-9CF6-36C01792B3EF.jpeg


Fan

8A92E138-1166-4F9E-90B1-F796B4941681.jpeg


Duct from lint trap to fan/blower/motor

9FE6E3C0-997C-49FC-AB33-BD0CCBDB67B6.jpeg


C0D23953-12F9-49A1-BDC2-A8B2303CCE0C.jpeg


Lint trap housing

A573881F-8039-44CE-B33C-D3F2008F181B.jpeg


A014E99D-A6F6-4C5D-AE27-E31C379080EA.jpeg


FAA65890-8F79-4F60-8146-1F440E6494A7.jpeg


9B575F05-FE0E-4B16-9CEF-05E99E82118D.jpeg


61E85B7C-7FEA-4D3C-B8A6-3678F872290B.jpeg


I don’t see any blockage after the drum.

The lint trap itself gets cleaned after every run, and I washed it with soap and water before I even started posting.

So if the flame is too lazy, what am I missing?
 

Jake

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The only thing I can see if the blower wheel blades have lint build-up on them.

I'd clean the blower wheel blades of that lint, then put the machine back together and try it out, if you still have this same problem, then I'm out of suggestions, you'd need a Whirlpool tech to come out and see why its doing this..

Jake
 

MxRacer965

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The blower wheel just had a very fine layer on some of the blades. If that’s all it takes to throw it off dryers are incredibly fragile...

AF26AE55-BD6B-41E6-B01D-8C2B0418A4E8.jpeg


But from the video you without a doubt believe the flame is lazy? Just with clothes in or even without clothes does the flame appear lazy? Should I even bother bypassing the high limit thermostat? I did get a new high limit thermostat and replaced it just for the hell of it. No change in behavior.

I noticed some foam “seals” at a number of the junctions between ducts...could there be excessive air loss at these if they aren’t sealing well enough?

I’m about ready to throw this thing outside and take a sledgehammer to it...
 

Jake

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