Compressor Overload (OL Activated)

What it means

This code appears on Daikin split, ducted and cassette air conditioners and means the compressor overload (OL) protection has tripped because the compressor ran too hot or drew too much current. The unit stops the compressor until it cools and then retries; a repeating code signals a real problem. The same code can mean something else on other brands.

Models covered: Daikin split air conditioners and Daikin ducted/cassette (SkyAir) units, which share the same error code system; the code shows on the wired remote or via the wireless remote check function.

Related codes: F3U0E6L5

Symptoms4

• The unit runs for a while, then the compressor stops and E5 appears.
• Weak cooling and a very hot outdoor unit.
• Trips happen more often in the hottest hours.
• Sometimes an unusual noise from the compressor.

Possible causes6

• Low refrigerant charge, so the compressor overheats from too little returning gas.
• A dirty condenser or weak outdoor fan raising pressure and temperature.
• A service valve not fully open or a restriction in the circuit.
• An electronic expansion valve fault.
• Low or unstable supply voltage.
• Internal compressor wear, or a fault in its protector or wiring.

How to diagnose5

1. Switch the unit off and let it cool, then make sure the outdoor unit is clean with clear airflow around it.
2. Check that the home supply voltage is stable.
3. A technician measures pressures and discharge line temperature against Daikin specifications to confirm the charge.
4. The technician checks the service valves and the electronic expansion valve.
5. The technician checks the compressor wiring, windings and protector per the service manual after discharging the inverter board.

How to fix5

1. Wash the outdoor unit and repair a weak outdoor fan.
2. Fit a voltage protector or fix a low voltage supply.
3. A licensed technician repairs any leak and recharges to the correct amount.
4. Replace the electronic expansion valve or repair compressor wiring as the tests show.
5. Replace the compressor if it has an internal fault, then run the unit for hours and confirm the code does not return.

Repair cost

In Saudi riyals; the highlighted part is the expected range for this fault.

The cost is low when a dirty outdoor unit or voltage is the cause, higher with a leak repair, and highest when a new inverter compressor is needed.

Prices are rough estimates including the part and the technician’s fee, and vary with brand, model and part source.
Prices last updated: September 2026

Frequently asked questions