Installation Guide
Tools Needed:
- Stacking kit (included)
- Adjustable wrench
- Level
- Screwdrivers (flat and Phillips)
- Pliers
- Tape measure
Step-by-Step Installation
- Choose Installation Location: Select a location with adequate space for both units, near necessary plumbing and electrical connections on a solid, level floor.
- Remove Shipping Materials: Remove all shipping bolts and packaging materials from both washer and dryer.
- Install Stacking Kit: Follow included instructions to properly install the stacking bracket system.
- Connect Water Supply: Connect hot and cold water supply lines to the washer's water inlet valves. Use only new hoses.
- Connect Drain Hose: Route the drain hose into a standpipe or laundry tub with a high loop to prevent backflow.
- Electrical Connection: Connect washer to 120V outlet and dryer to 240V outlet as required. Do not use extension cords.
- Level the Units: Adjust leveling legs to ensure both units are perfectly level and stable.
- Test Run: Run both units through complete cycles to check for proper operation and stability.
Specifications
| Model Series | WM3900HWA / DLEX3900W |
| Type | Stackable Front Load Washer and Electric Dryer |
| Color | White |
| Washer Capacity | 4.5 cu. ft. |
| Dryer Capacity | 7.4 cu. ft. |
| Noise Level (Washer) | 54 dB / 72 dB |
| Control Type | Touch Controls with LCD Display |
| Energy Rating | ENERGY STAR® Most Efficient |
| Washer Power Requirements | 120V, 60Hz, 15A |
| Dryer Power Requirements | 240V, 60Hz, 30A |
| Stacked Dimensions (HxWxD) | 145 x 60 x 75 cm |
| Weight (Combined) | 145 kg |
| Max Spin Speed | 1300 RPM |
Warranty Information
- Full Warranty: 1 year parts and labor
- Motor Warranty: 10 years on Direct Drive Motor
- Drum Warranty: 10 years on stainless steel drum
- Additional Coverage: Optional extended warranty available
For warranty service, contact LG Customer Service at 1-800-243-0000 or visit LG.com
Key Features
ThinQ Technology
Wi-Fi enabled for remote control via smartphone app, allowing you to monitor cycle status, download additional programs, and receive completion alerts for both washer and dryer.
Direct Drive Motor
LG's innovative Direct Drive motor connects directly to the drum without belts or pulleys, reducing noise and vibration while increasing reliability and efficiency.
Sensor Dry System
The dryer automatically senses moisture levels and adjusts drying time accordingly, preventing over-drying and saving energy while protecting your clothes.
Steam Technology
Both units feature steam technology to remove tough stains, reduce allergens, minimize wrinkles, and refresh clothes without washing.
TurboWash™ & TurboSteam™
Washer saves time with full loads in 59 minutes, while dryer refreshes clothes in just 20 minutes using powerful steam technology.
Stackable Design
Space-saving vertical design perfect for apartments, condos, and small laundry rooms while maintaining full-sized capacity.
Smart Pairing Features
Cycle Sync
Automatically coordinates washer and dryer cycles for optimal efficiency
Remote Start
Start laundry cycles from anywhere using the ThinQ app
Smart Diagnosis
Automatically diagnose issues and schedule service through the app
Usage Monitoring
Track energy and water usage to optimize laundry habits
Download Cycles
Access additional wash and dry cycles through the ThinQ app
Voice Control
Compatible with Google Assistant and Amazon Alexa
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Units won't start | Power issue, door not closed properly, stacking instability | Check power supply, ensure doors are latched, verify stacking kit installation |
| Vibration or noise | Unbalanced load, uneven floor, improper stacking | Redistribute load, level the units, check stacking bracket tightness |
| Poor drying results | Lint filter clogged, overloading, incorrect cycle | Clean lint filter, reduce load size, select appropriate dry cycle |
| Water not draining | Drain hose clogged or kinked, pump filter blocked | Check drain hose for obstructions, clean pump filter |
| Wi-Fi connection issues | Network problems, incorrect setup, signal strength | Check network connection, re-run setup, improve signal strength |
| Stack shifting | Improper installation, uneven surface, missing brackets | Reinstall stacking kit, ensure level surface, verify all brackets installed |
Error Codes
- IE: Water supply issue - Check water supply and inlet valve
- OE: Drain issue - Check drain hose and pump
- FE: Flooding detected - Check for leaks and water supply
- LE: Motor issue - Contact service center
- dE: Door not closed properly - Ensure door is fully closed
- tE: Temperature sensor error - Contact service center
- nF: No communication between units - Check connections and restart
Manual Downloads
Current Stackable Models
WM3900HWA / DLEX3900W
Stackable ThinQ Washer & Electric Dryer
WM4000HWA / DLGX4001W
Large Capacity Stackable Set
WM3500CW / DLE3500W
Compact Stackable Set
WM3900HBA / DLEX3900B
Black Stainless Stackable
Popular Previous Models
WM3470HVA / DLEX3470V
Previous Generation Stackable
WM3170CW / DLE3170W
Value Stackable Set
WM2240CW / DLE2240W
Compact Stackable
WM2688HNM / DLG2688N
Gas Dryer Stackable Set