Carrier 59SC2B Furnace Error Codes

Single Stage Gas Furnace | Control Board: HK42FZ034-type furnace control board

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Disclaimer
This information is for reference purposes only and does not guarantee accuracy or completeness. Always consult your owner's manual and a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk.

All Error Codes

Code Name Severity DIY?
LED Off (Continuous Off) No Power / Control Failure Critical ✗ Call a pro →
LED On (Continuous On) Normal Operation - No Call for Heat Info — →
Rapid Flashing Reversed Line Voltage Polarity High ✗ Call a pro →
Code 11 No Previous Code Info — →
Code 12 Blower On After Power Up Info — →
Code 13 Limit Circuit Lockout Critical ✓ Yes →
Code 14 Ignition Lockout Critical ✓ Yes →
Code 21 Gas Heating Lockout Critical ✗ Call a pro →
Code 22 Abnormal Flame-Proving Signal Critical ✗ Call a pro →
Code 23 Pressure Switch Did Not Open High ✗ Call a pro →
Code 24 Secondary Voltage Fuse Is Open High ✗ Call a pro →
Code 31 Pressure Switch Did Not Close or Reopened High ✓ Yes →
Code 33 Limit Circuit Fault High ✓ Yes →
Code 34 Ignition Proving Failure High ✓ Yes →
Code 45 Control Circuitry Lockout Critical ✗ Call a pro →

How to Read the Error Code

Two-digit LED status codes displayed by an amber LED on the furnace control board. The first digit is determined by the number of short flashes and the second digit by the number of long flashes. Three special non-numeric patterns also exist: continuous off, continuous on, and rapid flashing.

About This Model

The Carrier 59SC2B is a single stage gas furnace using the HK42FZ034-type furnace control board-series integrated furnace control (IFC) board.