High Pressure Protection

What it means

This code appears on Daikin air conditioners, most often on SkyAir ducted and cassette units fitted with a high pressure switch, and means the refrigerant discharge pressure exceeded the safe limit and the protection switch stopped the compressor. In hot weather 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.

Related codes: F6E7L4E5

Symptoms4

• The compressor stops and E3 appears, especially in the hottest afternoon hours.
• The unit runs briefly, trips and repeats.
• Air from the outdoor unit is very hot or weak.
• Weak cooling before the code appears.

Possible causes6

• A dirty or blocked outdoor condenser coil clogged with dust or leaves.
• A failed or weak outdoor fan, or its run capacitor on non-inverter models.
• A poorly placed outdoor unit, for example in an enclosed space that recirculates hot air.
• Refrigerant overcharge after incorrect charging.
• A service valve not fully open or a restriction in the refrigerant circuit.
• A faulty high pressure switch or its wiring.

How to diagnose5

1. Switch the unit off and make sure the outdoor unit is not covered and has enough clearance for airflow.
2. Inspect the condenser: heavy dust or leaves between the fins is a clear sign.
3. A technician confirms the outdoor fan runs at normal speed.
4. The technician measures operating pressures with gauges and compares them with Daikin specifications for the outdoor temperature.
5. The technician checks the high pressure switch, its wiring and the service valves.

How to fix5

1. Wash the condenser and outdoor unit fully and remove anything blocking airflow.
2. Improve the outdoor unit location or shade it without restricting the air discharge.
3. Repair the outdoor fan or replace its motor or capacitor.
4. A licensed technician corrects an overcharge or clears a restriction in the circuit.
5. Replace the high pressure switch if proven faulty, then test the unit in hot weather and confirm the code does not return.

Repair cost

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

A full outdoor unit wash solves many cases at moderate cost; the cost rises when a fan motor, a charge correction or a new pressure switch 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