Carrier error code E3
What it means
Low pressure protection.
Possible causes
Refrigerant leak or undercharge Restricted indoor airflow due to dirty filters Expansion device restriction
Suggested fix
Inspect filters and coils, read suction pressure and look for signs of leakage or frost; a technician should carry out leak repair and recharge using approved methods and correct any restrictions.
Safety first. Isolate the power supply before inspecting any unit. Refrigerant-circuit
and electrical repairs must be carried out by a qualified, registered technician.
Other Carrier codes
- E1 — High pressure protection in the refrigeration circuit.
- E2 — Evaporator coil temperature sensor fault.
- E4 — Compressor discharge temperature protection.
- E5 — Overcurrent or overload protection.
- E6 — Communication error between indoor and outdoor units.
- EC — Refrigerant leak detection alarm.
- F0 — Low refrigerant protection.
- P0 — High voltage protection.
- P1 — Low voltage protection.
- P4 — Fan speed fault.