LG WM3998 All-in-One Washer-Dryer Combo

The WM3998 is an all-in-one, ventless washer-dryer: it washes and dries in a single drum with no exhaust duct. That design drives a distinct failure set built around the condensation drying system. Here are the covered models, the recurring faults, the codes, the wear parts, and a repair-or-replace line tuned to a combo's shorter life.

Models covered#

Two variants built from 2019 to 2023 share the platform:

Common problems for this model#

Two of the top three are really the same story: the condensation loop has to shed all the moisture as heat, so a dirty condenser sits behind both slow drying and overheating.

Error codes#

• Error OE — drain / outlet fault
• Error LE — motor lock
• Error DE — door not sealed
• Error D80 — clean the condenser and filter

For anything else, unplug or trip the breaker for 60 seconds and restore power; a code that returns needs a diagnosis.

Wear parts#

Match the part number to your exact model before ordering:

Recall status#

There are no active recalls on the LG WM3998 series as of 2026-05-28. Check your model against the Consumer Product Safety Commission list at cpsc.gov from time to time.

Repair or replace?#

A combo works both drums hard, so it ages faster than a separate washer and dryer — the age line sits lower here. For the WM3998: under 8 years old with a fix below 50% of a comparable new combo, repair. Past 8 years, weigh the history; once repairs over the last 2-3 years top 40% of replacement, replace. Drain-pump and gasket jobs are always worth doing, while a bearing replacement on a unit past 8 years is the borderline call.

Keeping it healthy#

Nearly every WM3998 problem traces back to airflow through the condenser, so maintenance pays off here more than on most machines. Clean the condenser coil and filter every 2-3 months — it is the single biggest factor in drying speed. Do not load a full wash-and-dry to the brim; fill to 50-60% so the dry phase can keep up. Leave the door ajar between uses, since the sealed combo drum holds moisture and grows mold faster than a standalone washer.

FAQ#

Can an LG all-in-one really replace a separate washer and dryer?#

Functionally yes — it washes and dries in one ventless drum, ideal where a separate dryer will not fit. The trade-offs are real: drying runs 2-3 hours versus 45-60 minutes for a standalone, you cannot wash one load while drying another, and you should dry at 50-60% fill.

Why does my LG combo take so long to dry?#

Ventless condensation drying is simply slower than vented drying — it uses cool water over a condenser coil to pull moisture from the air instead of blowing it out a duct. Keep the condenser coil and filter clean every 2-3 months and avoid overloading the dry phase for the best times.

Is the mold on the door gasket normal?#

It is more common on a combo than on a standalone because the sealed drum stays damp between cycles. Wipe the boot dry and leave the door ajar after use; a badly fouled gasket (part MDS47123608) can be replaced.

Book an LG WM3998 repair#

We service LG combos across Sacramento and the Bay Area, and our techs stock the common WM3998 parts, so most visits finish same day. Book your repair for same-day or next-day service, upfront pricing, and a 90-day parts-and-labor warranty.