Lennox SLP98UHV Furnace Error Codes

Modulating Gas Furnace | Control Board: icomfort-enabled SureLight Variable Capacity Integrated Control

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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?
Device Communication Problem Device Communication Problem Critical ✗ Call a pro →
Low Line Voltage Low Line Voltage Medium ✗ Call a pro →
High Line Voltage High Line Voltage Medium ✗ Call a pro →
Line Voltage Frequency Out-of-Range Line Voltage Frequency Out-of-Range Medium ✗ Call a pro →
Low 24V Low 24V Medium ✗ Call a pro →
Unresponsive Device Unresponsive Device Medium ✗ Call a pro →
Thermostat Communication Lost Thermostat Communication Lost Critical ✗ Call a pro →
Control Self-Check Failed / Internal Hardware Error Control Self-Check Failed / Internal Hardware Error Critical ✗ Call a pro →
Internal Control Communication Failure Internal Control Communication Failure Critical ✗ Call a pro →
Corrupted Control Parameters Corrupted Control Parameters Critical ✗ Call a pro →
Outdoor Air Sensor Failure Outdoor Air Sensor Failure Low ✗ Call a pro →
Hard Lockout - Rollout Circuit Open Hard Lockout - Rollout Circuit Open Critical ✗ Call a pro →
Indoor Blower Communication Failure Indoor Blower Communication Failure Critical ✗ Call a pro →
Indoor Blower Motor Mismatch Indoor Blower Motor Mismatch Critical ✗ Call a pro →
Appliance Capacity/Size Not Programmed Appliance Capacity/Size Not Programmed Critical ✗ Call a pro →
Gas Valve Mis-Wired Gas Valve Mis-Wired Critical ✗ Call a pro →
Gas Valve Control Relay Contact Shorted Gas Valve Control Relay Contact Shorted Critical ✗ Call a pro →
Hot Surface Ignitor Open Hot Surface Ignitor Open Critical ✗ Call a pro →
Low Pressure Switch Failed Open Low Pressure Switch Failed Open Critical ✓ Yes →
Low Pressure Switch Failed Closed Low Pressure Switch Failed Closed Critical ✗ Call a pro →
High Pressure Switch Failed Open High Pressure Switch Failed Open Critical ✓ Yes →
High Pressure Switch Failed Closed High Pressure Switch Failed Closed Critical ✗ Call a pro →
Low Pressure Switch Open During Ignition/Run Low Pressure Switch Open During Ignition/Run Critical ✓ Yes →
Pressure Switch Calibration Failed Pressure Switch Calibration Failed Medium ✓ Yes →
Low Flame Current Low Flame Current Medium ✓ Yes →
Flame Sensed Out of Sequence Flame Sensed Out of Sequence Critical ✗ Call a pro →
Limit Switch Circuit Open Limit Switch Circuit Open Critical ✓ Yes →
Discharge Air Temperature Too High Discharge Air Temperature Too High Critical ✗ Call a pro →
Soft Lockout - No Flame Sensed Soft Lockout - No Flame Sensed Critical ✓ Yes →
Soft Lockout - Pressure Switch Failure During Retry Soft Lockout - Pressure Switch Failure During Retry Critical ✓ Yes →
Soft Lockout - Pressure Switch Recycle Failure Soft Lockout - Pressure Switch Recycle Failure Critical ✓ Yes →
Soft Lockout - Flame Failure Recycle Soft Lockout - Flame Failure Recycle Critical ✗ Call a pro →
Soft Lockout - Limit Circuit Recycle Soft Lockout - Limit Circuit Recycle Critical ✓ Yes →
Soft Lockout - Flame Out of Sequence Soft Lockout - Flame Out of Sequence Critical ✗ Call a pro →
Soft Lockout - Calibration Retry Exceeded Soft Lockout - Calibration Retry Exceeded Medium ✓ Yes →
Ignitor Circuit Fault Ignitor Circuit Fault Critical ✗ Call a pro →
Restricted Airflow Restricted Airflow Medium ✓ Yes →
Indoor Blower Motor Unable to Start Indoor Blower Motor Unable to Start Critical ✗ Call a pro →
Combustion Air Inducer Motor Amp Draw Too High Combustion Air Inducer Motor Amp Draw Too High Critical ✗ Call a pro →
Indoor Blower Motor Temperature Too High Indoor Blower Motor Temperature Too High Critical ✗ Call a pro →
Discharge Air Sensor Failure Discharge Air Sensor Failure Low ✗ Call a pro →
Heat Rate Reduced Due to Restricted Airflow Heat Rate Reduced Due to Restricted Airflow Medium ✓ Yes →
Restricted Airflow in Cooling/Continuous Fan Mode Restricted Airflow in Cooling/Continuous Fan Mode Medium ✓ Yes →
Indoor/Outdoor Unit Capacity Mismatch Indoor/Outdoor Unit Capacity Mismatch Low ✗ Call a pro →
Global Network Connection Problem Global Network Connection Problem Low ✗ Call a pro →
No Y1 Output to Non-Communicating Outdoor Unit No Y1 Output to Non-Communicating Outdoor Unit Critical ✗ Call a pro →
No Y2 Output to Non-Communicating Outdoor Unit No Y2 Output to Non-Communicating Outdoor Unit Critical ✗ Call a pro →
No R-to-O Output for Heat Pump No R-to-O Output for Heat Pump Medium ✗ Call a pro →
LSOM - Compressor Ran Over 18 Hours LSOM - Compressor Ran Over 18 Hours Medium ✗ Call a pro →
LSOM - Outdoor Unit System Pressure Trip LSOM - Outdoor Unit System Pressure Trip Critical ✗ Call a pro →
LSOM - Compressor Short-Cycling LSOM - Compressor Short-Cycling Critical ✗ Call a pro →
LSOM - Compressor Rotor Locked LSOM - Compressor Rotor Locked Critical ✗ Call a pro →
LSOM - Compressor Open Circuit LSOM - Compressor Open Circuit Critical ✗ Call a pro →
LSOM - Compressor Open Start Circuit LSOM - Compressor Open Start Circuit Critical ✗ Call a pro →
LSOM - Compressor Open Run Circuit LSOM - Compressor Open Run Circuit Critical ✗ Call a pro →
LSOM - Compressor Contactor Welded LSOM - Compressor Contactor Welded Critical ✗ Call a pro →
LSOM - Compressor Low Voltage LSOM - Compressor Low Voltage Medium ✗ Call a pro →

How to Read the Error Code

Alphanumeric codes displayed on a 7-segment LED. Status codes use letters (., A, C, d, h, H, df, U). Error codes use E prefix followed by 3-digit number (E105, E200, etc.). Press and hold diagnostic push button to cycle through menu; release on solid 'E' to enter Error Code Recall mode showing last 10 errors.

About This Model

The Lennox SLP98UHV is a modulating gas furnace using the icomfort-enabled SureLight Variable Capacity Integrated Control-series integrated furnace control (IFC) board.