LG WM3488HW Washer/Dryer Combo Not Drying

[Pomology]

I have an LG WM3488HW washer dryer combo that is not drying. I keep the lint cleaned out of the condensation tower in the back every few months, thus I know excess lint is not the reason for the poor performance.
 

 The wash cycle works perfectly. However once the dry cycle starts it only lasts apprx 10 to 15 minutes and then goes into cool down and acts like it thinks the clothes are dry. There are no error codes.  The clothes are warm so it appears the heating element works. The clothes remain a well-spun damp. 
 

I’m guessing perhaps the humidity sensing circuitry (is that the thermistors?) is broken making the dryer think the humidity is low and the clothes are dry, when in reality they are not. 

If anyone would be so kind as to give me their opinion I would be much grateful!

 Thanks!

 Randy

[Vance R]

From the look of the part diagram have you removed the fan motor assembly to check for lint buildup?

[Pomology]

Yes, I have done so and removed all lint from the fan.  
 

In the past when my machine has had lint buildup; it keeps trying to dry a load for hours and hours and at the end of 4 or 6 hours of attempted drying clothes are still damp. 

 

What it’s doing now is completely different.  Now after 15 minutes it seems to think everything is already dry and prematurely goes into cool down mode as though It had finished a successful dry cycle.  And after a little while in cool down mode the dry cycle will end and it will chime as it does when a load is dried successfully, and turn off. 
 

So it’s behaving much differently than it has in the past when it was merely suffering from lint buildup. 
 

I can only think it’s either a faulty sensor telling the dryer things are dry when they are not, or could I need a new controller board?  Any ideas are welcome!

Thank you!

Randy 

 

 

 

 

 

 

 

 

 

 

[Pomology]

Oh one other important thing I forgot to mention. This is an intermittent fault!  
 

Once out of every 5 or 10 loads, a load will dry correctly for a full normal dry cycle of a couple hours, come out bone dry!
 

The rest of the time it suffers from the problem above: drying For 10-15 minutes and then thinking it’s dry so going into cool down mode and finally turning off as though a load had successfully dried in 10 minutes!

[Vance R]

Fan motor runs when problems happens? If yes then check the thermistors.

[Pomology]

Thanks Vance!  

Yes, motor runs when problem happens.  And there are no fault codes - motor or otherwise - when problem happens. 

I will check the thermistors today and report. 

Thanks!

Randy

[Pomology]

Thanks Vance,

Appears the thermistors were the problem.

Replacing them.

Appreciate your input!

[Vance R]

You are welcome.