What does E3 mean?
Discharge pressure exceeded safety limit and high pressure switch opened.
Common causes
- Outdoor coil blocked or dirty
- Outdoor fan failure
- Refrigerant overcharge
- Ambient temperature too high
Diagnostic & testing steps
- 1. Clean outdoor coil
- 2. Verify outdoor fan runs during cooling
- 3. Check discharge pressure with compatible manifold
- 4. Measure subcooling - overcharge if >15°F
Tools required
- Daikin manifold gauges
- Multimeter
OEM parts & part numbers
Outdoor Fan Motor, Condenser Coil
Part numbers: KFQ32C403
Safety warning
⚠️ R-32 refrigerant is mildly flammable. Use only approved equipment.
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