LG Linear Compressor Loud Vibration: Troubleshooting... | appliancefaults.com

Technical Background:

The LG linear compressor is controlled by an inverter board and the main control unit (MCU). The MCU receives feedback from temperature sensors and controls the compressor's speed (RPM) via voltage regulation. Incorrect voltage or signals can cause erratic compressor operation. Voltage paths include 120V AC to the inverter board, then DC voltage to the compressor windings.

Symptoms:

The homeowner observes a loud vibrating noise coming from the rear of the LG refrigerator. The noise appears to be originating from the compressor area and ceases when the refrigerator door is opened.

Possible Causes:

Compressor mounting bolts loose.
Start relay or overload failure causing erratic compressor operation.
Compressor running at excessive RPM (software issue).
Damper door malfunction creating vacuum issue on compressor.
Evaporator fan hitting ice build-up due to defrost failure.
The linear compressor isolation system degraded.

Solution:

1

Unplug the refrigerator from the 120V AC outlet and engage Lock Out/Tag Out (LOTO).
2

Access the compressor compartment at the rear of the refrigerator.
3

Visually inspect the compressor mounting bolts for looseness. Tighten with a 10mm socket if needed, ensuring not to overtighten.
4

Check the compressor start relay and overload for visual damage. Use a multimeter to test for continuity. Replace if faulty.
5

With the refrigerator plugged in, and using extreme caution, check the voltage to the compressor using your multimeter. Note the running voltage.
6

Activate the refrigerator's diagnostic mode (if available - see expert tip below) to check the compressor RPM and error codes.
7

Inspect the damper door and evaporator fan for proper operation and ice buildup. Initiate a manual defrost cycle to melt any accumulated ice.

Safety Warning:

Disconnect power to the refrigerator before performing any repairs. High voltage is present in the compressor and inverter board area. Use Lock Out/Tag Out (LOTO) procedures to prevent accidental power restoration. Wear appropriate safety gear, including insulated gloves.

Prevention:

Periodically clean the condenser coils (at least every 6 months) to ensure proper heat dissipation. Avoid overloading the refrigerator to prevent excessive compressor workload.

Expert Tip:

Most LG refrigerators have a service mode. Often, pressing and holding the 'Freezer' and 'Ice Plus' buttons simultaneously for 5 seconds will enter diagnostic mode. This allows you to view error codes and run diagnostic tests.

Frequently Asked Questions

•What is the normal running voltage for an LG linear compressor?

The normal running voltage can vary depending on the model, but typically falls within a range of 30-120V DC. Refer to the service manual for the specific model.

•Where is the damper door located and how do I access it?

The damper door is usually located inside the refrigerator compartment, typically near the top, where the cold air enters from the freezer. Access usually requires removing the crisper drawers and/or shelving to expose the duct leading to the damper.

•How do I initiate a manual defrost cycle?

The procedure for initiating a manual defrost cycle varies by model. Typically, it involves entering the service mode (see expert tip) and selecting the defrost function. Refer to the service manual for the specific steps.

LG Linear Compressor Loud Vibration: Troubleshooting Guide

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What is the normal running voltage for an LG linear compressor?

•Where is the damper door located and how do I access it?

•How do I initiate a manual defrost cycle?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: