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Carrier Error Codes & Troubleshooting

Complete error code database and troubleshooting guide for Carrier systems. Find solutions to common issues or contact our experts.

Carrier Error Codes

Complete error code reference for Carrier systems. Each error code includes severity level, description, and troubleshooting steps.

C1
HIGH
Legacy 1902 PCB Error

Control board malfunction (Carrier heritage tech)

Power cycle system completely.

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C2
HIGH
Sensor Fault

Temperature/pressure sensor error

Check connections. Clean sensor.

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C3
HIGH
Compressor Error

Compressor not responding

Check electrical supply. Verify power.

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C4
HIGH
Fan Motor Issue

Indoor/outdoor fan malfunction

Check motor power and bearings.

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C5
URGENT
Refrigerant Critical

Refrigerant loss detected

Professional leak detection service.

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C6
URGENT
Pressure Out of Range

Abnormal system pressure

Shut down. Check all components.

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C7
HIGH
Temperature Error

Temperature sensor malfunction

Clean and check wiring.

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C8
HIGH
Outdoor Unit Fault

Outdoor board error

Verify power supply connections.

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C9
URGENT
Wrong Gas Type

Incorrect refrigerant detected

Professional evacuation immediately.

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C10
HIGH
Overload Protection

Compressor overload triggered

Allow cooling. Check conditions.

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C11
URGENT
Unit Communication Bad

Control signal transmission failed

Check cable connections.

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C12
MEDIUM
Filter Clogged

Air filter severely dirty

Replace with correct filter size.

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C13
HIGH
Condensate Blocked

Drain line obstruction

Clear drain immediately.

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C14
MEDIUM
Defrost Cycle Error

Winter defrost malfunction

Check outdoor ice buildup.

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C15
LOW
Mode Setting Error

Wrong operation mode

Set correct mode for season.

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C16
HIGH
Expansion Valve Fault

TXV malfunction

Refrigeration technician required.

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C17
HIGH
Power Supply Fault

Electrical problem detected

Check breaker and wiring.

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C18
MEDIUM
Coil Frozen

Outdoor heat exchanger iced

Manual defrost or COOL mode.

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C19
MEDIUM
Remote Control Error

Remote not communicating

Replace batteries. Check signal.

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C20
MEDIUM
Unusual Sound

Strange noises from system

Professional inspection needed.

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Preventative Care

Carrier Maintenance Tips

Regular maintenance helps prevent error codes and keeps your system running efficiently. Follow these Carrier-specific tips for optimal performance.

Still Need Help?

Our licensed technicians specialize in Carrier systems and are available 24/7 for emergency repairs and expert support.

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