Refrigerator Compressor Is Hot to the Touch? (LG & Samsung Diagnosis)

A refrigerator compressor that is very hot to the touch and not cooling typically indicates a mechanical failure or airflow obstruction. While compressors generate heat during normal operation, surface temperatures exceeding 150°F (65°C) suggest the component is overheating and may have tripped its thermal overload protector.

Common causes for this symptom include dirty condenser coils, a failed condenser fan motor, or internal mechanical failure in specific models like the LG Linear Compressor or Samsung Digital Inverter. Identifying the root cause quickly—and implementing preventative fridge compressor care tips—is essential to prevent permanent compressor damage.

In this guide, we will provide a step-by-step diagnostic procedure to determine why your refrigerator compressor is very hot not cooling, how to perform a safe “touch test,” and specific repair protocols for major brands including LG, Samsung, GE, and Whirlpool.

Safety First: The “Touch Test”

Before disassembling the appliance, it is necessary to differentiate between normal operating heat and critical overheating. Compressors rely on thermodynamics to compress gas, which naturally generates heat, but there is a strict safety limit.

The “3-Second Rule”

The quickest way to diagnose the temperature severity without tools is the “Touch Test.”

1. Unplug the refrigerator to eliminate electrical shock hazards.
2. Place your hand flat on the top of the black compressor dome.
3. The Result:
   • Warm (100°F – 110°F): Normal operation. If the fridge is not cooling, the fault is likely in the Defrost System or Evaporator Fan, not the compressor.
   • Hot (120°F – 130°F): Upper limit of normal. This often occurs during a long cooling cycle or after loading warm groceries.
   • Scorching (150°F+): Critical Overheating. If you cannot hold your hand on the casing for more than 3 seconds, the internal thermal overload has likely tripped.

When a compressor overheats, it will shut itself off to prevent a fire hazard. You may hear a distinct “click” followed by silence. If you hear this clicking sound, refer to our technical guide: Why Is My Refrigerator Clicking?.

Identify Your Compressor Type

Troubleshooting steps vary significantly based on the compressor technology. Identify your specific type below:

Standard Reciprocating (Old Style)

• Found in: GE, Frigidaire, Whirlpool, and older standard models.
• Behavior: Runs at 100% power until the target temperature is reached, then shuts off.
• Common Failure: The “Start Relay” burns out, causing the compressor to click and overheat.

Linear Compressor (LG)

• Found in: LG and Kenmore Elite models (2014+).
• Behavior: Runs constantly at varying speeds to maintain efficiency.
• Common Failure: Internal mechanical valve breakage. The motor runs, but pumps no refrigerant.

Inverter Compressor (Samsung)

• Found in: Samsung, Bosch, and GE Profile.
• Behavior: Controlled by a digital computer board (PCB); rarely stops running entirely.
• Common Failure: Inverter Control Board (PCB) failure or voltage irregularities.

The #1 Cause: Dirty Condenser Coils

The most common cause of compressor overheating is restricted airflow due to dust accumulation.

The refrigerator dissipates heat through the Condenser Coils located at the bottom or rear of the unit. If these coils are clogged with dust or pet hair, heat cannot escape. This forces the compressor to run continuously at high temperatures, similar to a car engine with a blocked radiator.

The Fix:

• Unplug the refrigerator.
• Remove the lower rear access panel.
• Use a dedicated coil brush to remove all dust and debris. (See full procedure: How to Clean Condenser Coils).
• Result: Compressor temperature should return to normal ranges within 2 hours.

Airflow Failure: Condenser Fan

Symptoms: Compressor is hot and vibrating, but the cabinet is warm.

The condenser fan is located directly next to the compressor. Its function is to pull cool air across the compressor and coils. If this fan fails, the compressor will overheat rapidly and shut down on thermal overload.

How to Diagnose:

1. Pull the fridge out and remove the back panel.
2. Plug the unit in and wait for the compressor to engage.
3. Inspect the fan operation:
   • Spinning fast: Functioning correctly.
   • Stopped/Twitching: The motor has failed or is receiving no power.
   • Obstructed: Inspect for physical blockages such as paper, mouse nesting, or debris jamming the blade.

The Fix: Replace the condenser fan motor. This is a standard DIY repair ($35–$50) that can prevent compressor failure.

Advanced: Multimeter Test

If the coils are clean and the fan is operational, the next step is to test the compressor windings for electrical continuity. This confirms if the internal motor windings have shorted or opened.

Safety Warning: Disconnect power before touching any electrical terminals.

Step 1: Measure Resistance

Remove the side cover to access the three terminal pins (Common, Start, Run). Set your digital multimeter to the 200Ω setting.

• Measure resistance between Pin 1 to 2, 2 to 3, and 1 to 3.
• Failure: If any reading is 0.0Ω (Short) or OL (Open Line), the compressor is electrically dead. A functional compressor typically shows readings between 3Ω and 15Ω.

Step 2: Ground Fault Test

Place one multimeter probe on a clean copper section of the compressor casing and the other on each pin sequentially.

• Result: The meter must show OL (Infinity).
• Failure: If any reading appears, the compressor is “grounded” and poses a severe electrocution hazard.

LG Guide: Linear Compressor

LG “Linear Compressors” (manufactured 2014–Present) have a documented high failure rate. This issue is caused by internal exhaust valve fatigue/breakage.

Symptoms of Failure

• The Hum: The unit runs continuously without cycling off.
• The Heat: The casing is extremely hot due to non-stop operation.
• No Cooling: The refrigerator maintains room temperature despite the compressor running.

The Verdict

This cannot be repaired with external parts. LG sometimes recommends a firmware update, but if the compressor is hot and the fridge is warm, it is a mechanical failure.

• Action: Verify warranty status immediately. LG has extended warranties (up to 10 years) covering this specific part. Do not install a hard start kit on an LG Linear compressor.

Samsung Guide: Inverter Compressor

Samsung compressors are driven by a variable-speed Inverter PCB. Unlike standard models, you will not hear a mechanical relay “click” upon failure.

Check the Blink Codes

1. Remove the small access panel on the upper rear of the refrigerator.
2. Locate the Red LED on the Inverter PCB.

Decode the Blinks:

• Solid Red: The board is functioning. The issue is likely a sealed system leak or mechanical compressor failure.
• 3 Blinks: Rotor Lock. The compressor is attempting to start but is mechanically seized.
• 5 Blinks: Low Voltage/Constraint. This typically indicates a board failure or input voltage issue.

The Fix: If the LED is blinking, replace the Inverter Board. If the LED is solid red (and the compressor is hot), it is likely a sealed system failure. (See: Samsung Error Codes).

The “Invisible” Problem: Freon Leak

If the compressor runs continuously and is hot to the touch, the system may be low on refrigerant (Freon).

Confirming a Leak: Inspect the evaporator coils located in the freezer section.

• Normal: A thin, even layer of frost covers all coils.
• Leak: A heavy ball of ice forms in one corner, while the rest of the coils are bare metal.

If a leak is confirmed, the appliance is generally considered irreparable due to the high cost of sealed system labor ($600+). This repair requires a licensed technician.

Standard Compressors: Start Relay

For GE, Whirlpool, or Frigidaire models: A hot compressor that clicks periodically but fails to start usually indicates a failed Start Relay/Overload Assembly.

The Fix: Remove the relay from the compressor pins and shake it. If it rattles, the internal components have shattered. Replace it with a 3-in-1 Hard Start Kit.

The 50% Rule: Repair vs. Replace?

Compressor and sealed system failures are the most expensive repairs in the appliance industry. Use the “50% Rule” to guide your decision:

• The Age Factor: If the refrigerator is over 10 years old, do not replace the compressor. Ancillary parts (seals, fans, boards) are likely near the end of their service life.
• The Cost Factor: Professional compressor replacement costs $600–$1,200. If this exceeds 50% of the cost of a comparable new refrigerator, replacement is the more economic choice.
• The Warranty Factor: Consult the user manual. Many manufacturers offer a standard 1-year warranty on the general unit but a 5-year or 10-year extended warranty specifically for the “Sealed System” (Compressor).

Summary: Action Plan

Frequently Asked Questions

Q: Is it dangerous if my Samsung compressor is hot to the touch?
A: Yes. If the surface is too hot to hold your hand on, the thermal overload is likely tripping. This thermal stress can degrade internal oil and lead to permanent seizure.

Q: How do I cool down a hot refrigerator compressor?
A: Unplug the refrigerator immediately. Direct a standard household fan at the compressor compartment for 60 minutes. Once the unit is cool, follow standard fridge compressor care tips like cleaning the dust off the coils before plugging it back in.

Q: Why does my fridge make a clicking noise every few minutes?
A: This sound is the Thermal Overload Protector tripping. It indicates the start relay has failed or the compressor is mechanically seized and drawing excessive amperage.

Q: How can I prevent the compressor from overheating again?
A: Airflow is key. One of the most important fridge compressor care tips is to pull the refrigerator away from the wall at least once a year to vacuum the condenser coils and ensure the cooling fan is spinning freely.