Discharge Pipe Temperature Control

What it means

This code appears on Daikin split, ducted and cassette air conditioners and means the temperature of the compressor discharge pipe rose above the safe limit, so the unit stopped the compressor to protect it. The usual cause is low refrigerant or a refrigerant flow control fault, and repeated trips put the compressor at risk. 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: J3U0E9E5

Symptoms4

• The compressor stops after a period of running and F3 appears.
• Weak cooling and a noticeably hot outdoor unit.
• The unit restarts after cooling down, then trips again.
• The compressor may sound louder than usual.

Possible causes6

• Low refrigerant charge from a leak.
• An electronic expansion valve fault restricting flow.
• A service valve not fully open or a restriction in the circuit.
• A dirty condenser or weak outdoor fan raising operating temperature.
• A discharge pipe thermistor that has come loose or reads wrongly.
• Internal compressor wear causing it to run hot.

How to diagnose5

1. Switch the unit off and let it cool, then make sure the outdoor unit is clean with free airflow.
2. A technician confirms the discharge thermistor is fixed on the pipe and reads sensibly against the Daikin table.
3. The technician measures pressures and pipe temperatures to assess the charge.
4. The technician checks the service valves and the operation of the electronic expansion valve.
5. If the circuit is sound but the temperature is high, the compressor is examined.

How to fix5

1. Clean the outdoor unit and repair a weak outdoor fan.
2. Refit the discharge thermistor, or replace it if it reads wrongly.
3. A licensed technician repairs the leak and recharges to the correct amount.
4. Open the service valves fully or replace the electronic expansion valve as the tests show.
5. Run the unit for a long period, watch the discharge temperature and confirm the code does not return.

Repair cost

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

Refitting the sensor or cleaning the unit is cheap; the cost rises with a leak repair and recharge or a new expansion valve.

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