High Pressure Control in Cooling

Home Appliance Error Codes Daikin Split AC

Can you still use it? With care until repaired

Who can fix it? Needs a technician

Typical repair time 1 hour – 3 hours

Typical cost SAR 150 to 1,100

What it means

This code appears on Daikin split, ducted and cassette air conditioners and means the unit detected high condensing pressure in cooling, usually from a high outdoor heat exchanger temperature, and reduced output or stopped the compressor to protect it. In summer the usual cause is a dirty or blocked condenser or an outdoor fan 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.

Symptoms4

Weak cooling in the hottest hours, then code F6.
The compressor cycles on and off repeatedly.
Very hot air from the outdoor unit.
The code disappears at night or on cooler days.

Possible causes6

An outdoor condenser coil caked with dust and sand or blocked by leaves.
A weak or slow outdoor fan.
An outdoor unit in a tight or enclosed space that recirculates hot air.
Refrigerant overcharge.
A faulty outdoor heat exchanger thermistor reading falsely high.
A restriction in the refrigerant circuit, which is the least common cause.

How to diagnose5

Switch the unit off and inspect the outdoor unit: are the fins covered in dust, and is there enough clearance?
Make sure the outdoor unit is not in an enclosed sunny spot or in another unit's hot exhaust.
A technician checks the outdoor fan speed.
The technician measures pressures against Daikin specifications for the outdoor temperature.
The technician measures the outdoor heat exchanger thermistor against the manufacturer table.

How to fix5

Give the condenser and outdoor unit a full wash.
Improve ventilation around the outdoor unit, or move it if it recirculates hot air.
Repair the outdoor fan or replace its motor.
A licensed technician corrects an overcharge, or the heat exchanger thermistor is replaced if faulty.
Test the unit in hot weather and confirm the code does not return.

Repair cost

0–200

200–600

600–1,500

1,500+

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

A full outdoor unit wash fixes most cases; the cost rises when a fan motor or a refrigerant charge correction 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

What is the difference between F6 and E3?

F6 is a preventive control, usually based on a temperature reading, that cuts output early, while E3 means the high pressure switch actually tripped. The causes overlap, with a dirty condenser at the top.

Does shading the outdoor unit help?

Yes, if the shade is high and does not block air in or out. Poor shading that traps hot air makes the problem worse.

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This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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