LG Refrigerator LMXS30776S Service Manual

The LG Refrigerator LMXS30776S is a 30 cubic foot French Door refrigerator with InstaView Door-in-Door, Craft Ice™ maker, Smart Cooling Plus™ system, linear compressor, and Wi-Fi connectivity. This service manual provides authorized technicians with detailed information for installation, diagnosis, repair, and maintenance. Below are key sections covering safety, specifications, component locations, disassembly, troubleshooting, and parts lists.

1. Safety Precautions 2. Model Specifications 3. Component Locations & Diagrams 4. Installation Instructions 5. Disassembly & Reassembly Procedures 6. Electrical System 7. Refrigeration System 8. Control System & Diagnostics 9. Error Code Troubleshooting 10. Parts List & Exploded Views 11. Performance Test Data

Safety Precautions

Before servicing, read all safety warnings. Disconnect power before accessing electrical components.

Hazard	Precaution
Electrical Shock	Unplug unit or disconnect circuit breaker. Verify with voltmeter.
Refrigerant	Use certified recovery equipment. Avoid open flames.
Sharp Edges	Wear cut-resistant gloves when handling panels and shelves.
Heavy Components	Use proper lifting techniques; two-person lift for compressor.
Chemical Exposure	Wear safety glasses and gloves when handling refrigerants or cleaning agents.

Model Specifications

Model: LMXS30776S
Type: French Door Bottom Freezer with InstaView
Total Capacity: 30 cu. ft.
Refrigerant: R-600a (Isobutane)
Compressor: Linear Inverter Compressor
Voltage: 115 VAC, 60 Hz
Amperage: 6.5 A (Running)
Defrost System: Adaptive Defrost with Heater
Ice System: Craft Ice™ Sphere Maker & Dispenser
Connectivity: Wi-Fi (LG ThinQ® enabled)

Component Locations & Diagrams

Main components: Control board, linear compressor, evaporator fan, condenser fan, damper assembly, ice maker assembly, water valve, temperature sensors.

Main Control Board: Located behind the kick plate at the front bottom.
Linear Compressor: Rear bottom, enclosed in sound-dampening cover.
Evaporator & Fans: Behind rear panel in freezer compartment.
Ice Maker Assembly: Upper left of freezer door.
Temperature Sensors: Fridge compartment (2), freezer compartment (1), evaporator (1).

WARNING! Refer to diagrams before disassembly to avoid damage to wire harnesses.

Installation Instructions

Proper installation ensures optimal performance and warranty compliance.

Clearance: Allow 2" minimum on sides, 4" at rear, and 1" top for ventilation.
Leveling: Adjust front leveling legs; unit must be level side-to-side, slightly tilted backward.
Water Connection: Connect to cold water line with 1/4" copper tubing and shut-off valve.
Electrical: Dedicated 115V, 15A grounded outlet.
Door Alignment: Adjust hinges if doors are not sealing evenly.
Initial Power-Up: Allow 24 hours for temperatures to stabilize before loading food.

CAUTION! Do not install near heat sources. Ensure water line is leak-free.

Disassembly & Reassembly Procedures

Step-by-step guide for accessing key components.

To Access Main Control Board:

Unplug refrigerator.
Remove kick plate (snap-fit, pry gently at top).
Remove front lower cover screws (2).
Slide cover forward to reveal control board.
Disconnect wire harnesses noting positions.

To Access Evaporator:

Remove all freezer drawers and shelves.
Remove rear panel screws (6).
Carefully pull panel away to access evaporator and fans.

Tip: Take photos during disassembly for reference during reassembly.

Electrical System

Circuit diagrams and voltage specifications for major components.

Component	Test Point	Expected Value
Main Control Board Input	L1 to N	115 VAC ±10%
Compressor Terminals	Between P1-P2	80-160 VAC (varies with load)
Evaporator Fan Motor	Red to White wire	12 VDC
Damper Motor	Connector pins 1-2	5 VDC (pulsed)
Ice Maker Assembly	Harness connector	120 VAC when calling for ice

WARNING! Always disconnect power before performing continuity or resistance checks.

Refrigeration System

Sealed system using R-600a refrigerant. Service requires EPA 608 Type II certification.

Compressor: Linear type (P/N 6321ER1004A). Oil charge: 4.5 oz POE.
Evaporator: Plate and fin type, located behind freezer rear panel.
Condenser: Serpentine coil, bottom rear, forced air via fan.
Capillary Tube: Metering device, paired with accumulator.
Filter-Drier: Bi-flow type, located near compressor.
Refrigerant Charge: 2.3 oz R-600a. CRITICAL: Weigh-in charge only.

CAUTION! R-600a is flammable. No brazing on sealed system without proper purging.

Control System & Diagnostics

The main control board monitors sensors and controls all functions. Access diagnostic mode.

Entering Diagnostic Mode:

Press and hold Ice Type and Ice Plus buttons on dispenser panel for 8 seconds.
Display will show "dIAG".
Use Temp buttons to scroll through test functions.
Press Ice Type to select a test.

Key Tests: Compressor Relay, Fan Test, Defrost Heater, Valve Test, Sensor Readouts.

Error Code Troubleshooting

Error Code	Description	Possible Cause	Corrective Action
FF / EF	Freezer Fan Fault	Obstructed fan, bad motor, wiring	Check for ice blockage, test fan motor resistance (50-200 Ω).
PF	Power Failure	Power interruption > 2 hours	Reset by cycling power. Check outlet.
dH / CH	Door Open Alert	Door not fully closed	Check door alignment, gasket, hinge.
IE / ICE	Ice Maker Fault	Jam, low water pressure, faulty fill cup	Clear ice jam, check water pressure (20-120 psi).
LE / LF	Linear Compressor Fault	Overload, start failure, board fault	Check compressor windings (P1-C: 10Ω, P2-C: 20Ω).

Parts List & Exploded Views

Key replacement parts for model LMXS30776S.

Main Control Board: P/N 6321ER1004A
Linear Compressor Assembly: P/N 6738B0012A
Evaporator Fan Motor: P/N 5309ER1002B
Craft Ice Maker Assembly: P/N 6753ER1001A
Water Inlet Valve: P/N 5309ER1001C
Temperature Sensor (Fridge): P/N 5309ER1003A
Door Gasket Set (French Door): P/N MCS22477802

Note: Always verify part number with serial number of unit before ordering.

Performance Test Data

Expected operating parameters under normal ambient conditions (70°F).

Parameter	Refrigerator Compartment	Freezer Compartment
Set Point	37°F	0°F
Actual Temp Range	34°F - 40°F	-2°F to +5°F
Compressor Run Time	40-60% duty cycle
Evaporator Temp (During Cooling)	N/A	10°F to 20°F
Condenser Discharge Air Temp	90°F - 115°F above ambient

Reset to Factory Defaults: In diagnostic mode, select "INIT" option.

Service Support: LG Service Network: 1-800-243-0000. Tech Website: www.lgservice.com