Installation Guide
Tools Needed:
- Adjustable wrench
- Level
- Screwdrivers (flat and Phillips)
- Pliers
- Tape measure
- Drain hose adapter
Step-by-Step Installation
- Choose Installation Location: Select a location near necessary plumbing and electrical connections on a solid, level floor with proper ventilation.
- Remove Shipping Materials: Remove all shipping bolts and packaging materials from the washer dryer combo unit.
- Connect Water Supply: Connect hot and cold water supply lines to the water inlet valves. Use only new, high-quality hoses.
- Connect Drain System: Route the drain hose into a standpipe with proper height requirements to prevent backflow and siphoning.
- Ventilation Setup: Install proper exhaust venting for dryer function according to local building codes.
- Electrical Connection: Connect to a properly grounded 240V outlet for dryer function and 120V for washer function.
- Level the Unit: Adjust the leveling legs to ensure the washer dryer is perfectly level in all directions.
- Test Run: Run both washing and drying cycles to check for proper operation, leaks, and ventilation.
Specifications
| Model Series | WM3900HWA |
| Type | Front Load Washer Dryer Combo |
| Color | Graphite Steel / White |
| Washer Capacity | 4.5 cu. ft. |
| Dryer Capacity | 7.4 cu. ft. |
| Noise Level (Wash/Spin/Dry) | 52 dB / 68 dB / 65 dB |
| Control Type | Touch Controls with LCD Display |
| Energy Rating | ENERGY STAR® Certified |
| Water Consumption | 12.8 gallons per cycle |
| Power Requirements | 240V/120V, 60Hz, 30A |
| Dimensions (HxWxD) | 74 x 27 x 32 inches |
| Weight | 205 lbs |
| Max Spin Speed | 1300 RPM |
| Dryer Technology | Heat Pump Drying |
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/support
Key Features
ThinQ Smart Technology
Wi-Fi enabled for remote control via smartphone app, allowing you to start, monitor, and receive alerts for both wash and dry cycles from anywhere.
All-in-One Design
Combines washing and drying functions in a single unit, saving space and eliminating the need to transfer laundry between machines.
Direct Drive Motor
LG's innovative Direct Drive motor connects directly to the drum without belts, reducing noise and vibration while increasing reliability.
Heat Pump Drying
Energy-efficient heat pump technology uses less energy than conventional dryers while being gentle on fabrics.
Steam Technology
SteamRefresh® cycle reduces wrinkles and odors, while SteamWash® helps remove tough stains and allergens.
TurboWash™ 360°
Complete a full load in just 30 minutes using powerful jet sprays and optimized drum rotations that reach all areas of the load.
Smart Functions
Remote Start
Start wash and dry cycles remotely using the ThinQ app on your smartphone
Cycle Monitoring
Monitor cycle progress and receive completion alerts on your mobile device
Diagnostics
Smart diagnostics can identify issues and provide troubleshooting guidance
Software Updates
Receive over-the-air updates with new features and cycle optimizations
Energy Monitoring
Track energy and water usage through the ThinQ app
Voice Control
Compatible with Google Assistant and Amazon Alexa for voice commands
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Unit won't start | Power issue, door not closed, control lock activated | Check power supply, ensure door is latched, check control lock settings |
| Clothes still wet after drying | Overloading, lint filter clogged, improper cycle selection | Reduce load size, clean lint filter, select appropriate dry cycle |
| Water not draining | Drain hose clogged or kinked, pump filter blocked | Check drain hose for obstructions, clean pump filter |
| Leaking water | Door not sealed, overfilling, loose connections | Check door seal, ensure proper detergent amount, check connections |
| Unusual noises during operation | Foreign objects in drum, unbalanced load, installation issues | Check for foreign objects, redistribute load, verify proper installation |
| Error codes displayed | Various system malfunctions | Refer to error code section in manual, contact service if persistent |
Common 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
- UE: Unbalanced load - Redistribute clothes and restart
- tE: Temperature sensor error - Contact service center
- HE: Heater error - Check dryer heating system
Manual Downloads
Current ThinQ Washer Dryer Models
WM3900HWA
4.5 cu. ft. Smart Combo
WM4000HBA
4.5 cu. ft. Black Stainless
WM3900HWA
4.5 cu. ft. Graphite Steel
WM3500HWA
4.5 cu. ft. White Combo
Popular Previous Models
WM3488HW
2.3 cu. ft. Compact Combo
WM3997HWA
4.3 cu. ft. Smart Combo
WM3070HW
4.2 cu. ft. Standard Combo
WM3455HW
4.2 cu. ft. White Combo