LG WM3988HWA is full of water at END OF CYCLE when the DRY option is set

Sears Parts Direct is one source of the parts diagrams, https://www.searspartsdirect.com/model/1vc37q1bdj-003204/lg-wm3987hw-washer-parts . See the Dispenser assembly parts diagram for the water inlet valve. If you can watch the entire cycle, try turning off the shut-off valves for the washer inlet hoses after the rinse cycle and before the dry cycle starts. Water should not flow into the washer/dryer with the shut-offs closed.

I've seen inlet valve solenoids fail in the open position or in the closed position. I've never seen a control board that sent open messages randomly. (Sometimes, there is damage to the control board or corrosion or damaged wiring that stops the control board from sending the open/closed message to the solenoid.)

I hope this helps.

Cindy Wells

Hi there. In some cases if your dryer vent tube is bunched up behind the dryer and not extended properly or if vent tube is running up the wall to be vented to the outside it will cause water to build up in dryer vent tube. Make sure your flexible dryer tubing is not full of water or clogged with lint and make sure if you have an extended piece that goes to outside ventilation that that is not clogged with lint as well. Hope this helps you with your drying issues.
Cathy

One of the inlet water valves is not working

I have an earlier version of your machine (WM3988HWA). What I've found is that you can't use the Spinsense feature if you've got the Dry cycle set to go after your wash. I have no idea why they designed it this way!
We run the wash first without setting it to dry, and have no problem turning Spinsense on. I usually hold it down for 3 second after hitting the start button, but you can also do it before you start the wash. When the wash is done, then we start a dry cycle.
This is the main flaw with our otherwise great machine. I posted about it at http://www.fixya.com/ThreadAsker.aspx?thid=1844295 a long time ago but never got any advice.

try different combination. if snag persists, software problem

Sorry but you only have the one speed on this particular brand. Perm and short are just less time. The best thing to do is always use large water setting and less delicates in the load on a short cycle to compensate for the speed and protect your delicate fabrics.

Remove the cord, wash in warm water on perm press cycle, and either dry on perm press, or hang

You may not be getting sufficient air flow--remove the lint filter and wash it with detergent and hot water. Also clean excessive lint out of the air vents (under the filter too). Don't use 'perm press' if you want things absolutely dry. Remove and hang up before they cool. 'Damp dry' really means 'don't dry' I guess!

CHECK THE WATER FILTERS AT THE BACK OF THE UNIT THEY ARE PROBABLY DUE FOR A CLEANING.

Heater is used to both heat water during clean cycle and dry dishes after wash cycle. Most washers have either a separate switch for Heat or Dry for optional use, or some have the water heat and dish dry options built into cycle set options.

You can save money by turning off the Dish Dry option since it is a very in-efficient way to dry dishes. Instead, open the wishwasher door after washing cycle completes, just enough so fresh air can get into, and humid air can escape, dishwasher.

Water Heat option is only needed for dried food on dishes, and is never needed if dishes are either rised off before putting them in the dishwasher, or rinsed off inside the dishwaser with a Rinse cycle, if they are to stand for a time waiting for a full dishwasher for wash.