Comprehensive Guide to HVAC Error Codes

In the modern world of heating, ventilation, and air conditioning (HVAC), understanding error codes is crucial for diagnosing system issues. When your HVAC system malfunctions, it often presents an error code, offering insight into what may be wrong. These codes are essential for professional technicians and homeowners alike to understand the issue’s cause, ranging from minor sensor malfunctions to critical system failures.

In this comprehensive guide, we will explore the top error codes for 12 major HVAC brands: Lennox, Trane, Carrier, Goodman, Viessmann, Rinnai, Rheem, Daikin, Bryant, Amana, Ruud, York, and Navien. We’ll decode error codes for each brand to help you understand what they mean and what actions to take.

Lennox HVAC Error Codes

Lennox HVAC systems are known for their reliability, but like all HVAC systems, they can experience problems. Here are 20 common Lennox error codes:

1. E200: High Limit Switch Open – The limit switch has tripped due to overheating.
2. E201: Pressure Switch Open – Indicates an issue with the pressure switch not closing.
3. E202: Flame Sensor Failure – The sensor is unable to detect a flame, preventing the system from heating.
4. E203: Ignition Failure – The system failed to ignite after several attempts.
5. E204: Low Flame Signal – The flame signal is weaker than expected.
6. E205: Gas Valve Fault – There’s an issue with the gas valve operation.
7. E206: Communication Error – The indoor and outdoor units are unable to communicate.
8. E207: Airflow Problem – An airflow issue, potentially due to a blocked filter or fan malfunction.
9. E208: Refrigerant Low – The system is low on refrigerant, which affects cooling performance.
10. E209: Defrost Error – The defrost cycle is not functioning properly in heat pump mode.
11. E210: Outdoor Coil Temperature Sensor Failure – The outdoor coil sensor is faulty.
12. E211: Indoor Coil Temperature Sensor Failure – The indoor coil sensor has malfunctioned.
13. E212: High Pressure Switch Open – Indicates high pressure in the refrigerant system.
14. E213: Low Pressure Switch Open – Low refrigerant pressure is causing the system to shut down.
15. E214: Compressor Overload – The compressor is drawing too much power.
16. E215: Condensate Pump Failure – The pump responsible for removing condensation has failed.
17. E216: Exhaust Temperature Error – The exhaust temperature is outside of safe operating parameters.
18. E217: Blower Motor Failure – The blower motor is not operating.
19. E218: Compressor Lockout – The compressor has locked out due to an error condition.
20. E219: Furnace Lockout – The furnace has locked out after several failed ignition attempts.

Trane HVAC Error Codes

Trane HVAC systems are synonymous with durability and innovation, but error codes can still occur. Here are 20 common Trane error codes:

1. E1: Communication Error – Indicates a failure in communication between the indoor and outdoor units.
2. E2: Pressure Sensor Fault – Pressure sensor readings are outside the normal range.
3. E3: High Temperature Lockout – The system is shutting down due to high internal temperatures.
4. E4: Low Temperature Lockout – The system is shutting down due to excessively low temperatures.
5. E5: Defrost Mode Error – The heat pump’s defrost cycle has malfunctioned.
6. E6: Compressor Overload – The compressor is overheating.
7. E7: Low Refrigerant – The system is detecting a low refrigerant level.
8. E8: Condenser Fan Motor Failure – The fan motor in the condenser unit is not running.
9. E9: Indoor Temperature Sensor Failure – The sensor inside the unit has failed.
10. E10: Thermostat Communication Failure – The thermostat is not communicating with the main control board.
11. E11: Outdoor Coil Temperature Sensor Failure – The outdoor coil sensor has failed.
12. E12: High Pressure Lockout – The high-pressure switch is open due to excessive pressure.
13. E13: Low Pressure Lockout – The low-pressure switch is open due to insufficient refrigerant pressure.
14. E14: Flame Sensor Error – The system is unable to detect a flame during ignition.
15. E15: Gas Valve Malfunction – The gas valve is not opening or closing properly.
16. E16: Ignition Failure – The system failed to ignite after several attempts.
17. E17: Fan Speed Error – The blower motor is running at an incorrect speed.
18. E18: Frozen Coil – The evaporator coil has frozen, potentially due to airflow restrictions.
19. E19: Indoor Blower Motor Error – The blower motor inside the unit is malfunctioning.
20. E20: Heat Exchanger Overheat – The heat exchanger is overheating due to poor airflow or malfunctioning components.

Carrier HVAC Error Codes

Carrier is a leading name in HVAC technology, and their systems are widely regarded for their efficiency. Here are 20 common Carrier error codes:

1. 31: Pressure Switch Fault – The pressure switch is stuck or not operating correctly.
2. 32: Low Pressure Lockout – The system is low on refrigerant.
3. 33: Limit Switch Fault – The high limit switch has tripped, possibly due to overheating.
4. 34: Ignition Failure – The furnace failed to ignite after several attempts.
5. 35: Flame Sensor Failure – The flame sensor is not detecting a flame.
6. 36: Inducer Motor Error – The inducer motor is not operating properly.
7. 37: Gas Valve Fault – The gas valve is not opening or closing correctly.
8. 38: Compressor Overload – The compressor is drawing excessive current.
9. 39: High Pressure Lockout – The high-pressure switch is open due to excessive refrigerant pressure.
10. 40: Low Pressure Lockout – The system is shutting down due to low refrigerant pressure.
11. 41: Thermostat Communication Error – The thermostat is not communicating with the system.
12. 42: Blower Motor Error – The blower motor is malfunctioning.
13. 43: Defrost Error – The defrost cycle in the heat pump is not working correctly.
14. 44: Heat Exchanger Overheat – The heat exchanger has overheated due to restricted airflow.
15. 45: Indoor Coil Freeze – The evaporator coil has frozen, indicating an airflow or refrigerant issue.
16. 46: Outdoor Coil Sensor Failure – The sensor on the outdoor coil has failed.
17. 47: Indoor Coil Sensor Failure – The sensor on the indoor coil is malfunctioning.
18. 48: High Temperature Lockout – The system is shutting down due to excessively high temperatures.
19. 49: Low Temperature Lockout – The system is shutting down due to low temperatures.
20. 50: Condensate Pump Failure – The pump responsible for draining condensate has stopped working.

Goodman HVAC Error Codes

Goodman HVAC systems are widely used for their cost-effectiveness and efficiency. Here are 20 common Goodman error codes:

1. E0: No Fault Detected – No issues present.
2. E1: System Lockout – The system has locked out due to multiple failed ignition attempts.
3. E2: Flame Failure – The flame sensor is not detecting a flame.
4. E3: Pressure Switch Open – The pressure switch did not close within the required time frame.
5. E4: Open High Limit – The high limit switch has tripped due to overheating.
6. E5: Open Rollout Switch – The rollout switch has detected a flame where it shouldn’t be.
7. E6: Gas Valve Circuit Open – There is a problem with the gas valve circuit.
8. E7: Vent Pressure Fault – The vent pressure is too high or too low.
9. E8: High Temperature Lockout – The system is shutting down due to high temperatures.
10. E9: Low Temperature Lockout – The system is shutting down due to low temperatures.
11. EA: Defrost Mode Active – The system is in defrost mode.
12. EB: Defrost Mode Error – The system encountered an error during the defrost cycle.
13. EC: Compressor Overload – The compressor is overheating.
14. ED: Refrigerant Leak – A leak is detected in the refrigerant system.
15. EE: Outdoor Coil Sensor Fault – The sensor on the outdoor coil has failed.
16. EF: Indoor Coil Sensor Fault – The sensor on the indoor coil is malfunctioning.
17. EG: Blower Motor Fault – The blower motor is not functioning properly.
18. EH: Thermostat Communication Error – The thermostat is not communicating with the main control board.
19. EI: Heat Exchanger Overheat – The heat exchanger has overheated.
20. EJ: Low Refrigerant – The system is low on refrigerant and needs a recharge.

Viessmann HVAC Error Codes

Viessmann is known for its high-efficiency boilers and heating systems. However, error codes can appear when issues arise. Here are 20 common Viessmann error codes:

1. F2: Flame Sensor Error – The flame sensor cannot detect a flame during ignition.
2. F4: Ignition Failure – The system has failed to ignite after several attempts.
3. F5: Boiler Overheat – The boiler is overheating, likely due to restricted water flow.
4. F6: No Water Flow – The system is detecting no water flow, possibly due to pump failure.
5. F7: Pressure Sensor Error – The pressure sensor is not reading correctly.
6. F8: Gas Valve Fault – There is an issue with the operation of the gas valve.
7. F9: Low Pressure – The system pressure is below the required level.
8. FA: High Pressure – The system pressure is too high and must be relieved.
9. FB: Outdoor Temperature Sensor Error – The outdoor temperature sensor has malfunctioned.
10. FC: Flow Sensor Error – The flow sensor is malfunctioning or not detecting flow.
11. FD: Heat Exchanger Temperature High – The heat exchanger temperature is exceeding safe levels.
12. FE: Condensate Trap Blocked – The condensate drain is blocked, preventing proper drainage.
13. FF: Internal Communication Failure – There is a communication issue between internal system components.
14. H0: Fan Speed Error – The fan is not operating at the correct speed.
15. H1: Ignition Lockout – The boiler has locked out after repeated ignition failures.
16. H2: Flame Loss – The flame is being extinguished during operation.
17. H3: Water Temperature High – The water temperature has exceeded safe operating levels.
18. H4: Gas Supply Issue – The system is detecting insufficient gas supply.
19. H5: Ventilation Error – The ventilation system is not operating correctly, leading to pressure buildup.
20. H6: Boiler Lockout – The boiler has shut down due to multiple errors.

Rinnai HVAC Error Codes

Rinnai specializes in tankless water heaters and HVAC systems, which sometimes encounter error codes. Here are 20 common Rinnai error codes:

1. Error Code 02: No Burner Ignition – The system fails to ignite the burner.
2. Error Code 05: Water Flow Error – Insufficient water flow through the system.
3. Error Code 10: Air Supply or Exhaust Blockage – There is a blockage in the air supply or exhaust.
4. Error Code 11: Ignition Failure – The system fails to ignite after several attempts.
5. Error Code 12: Flame Loss – The flame is extinguished during operation.
6. Error Code 14: Thermal Fuse Failure – The thermal fuse has blown, indicating overheating.
7. Error Code 16: Over Temperature Warning – The system water temperature is too high.
8. Error Code 19: Electrical Grounding Fault – There is a grounding issue with the electrical system.
9. Error Code 25: Condensate Trap Blocked – The condensate drain is blocked or malfunctioning.
10. Error Code 30: Venting Problem – The vent system is blocked or not working properly.
11. Error Code 31: Burner Sensor Fault – The burner sensor is malfunctioning.
12. Error Code 32: Heat Exchanger Temperature Sensor Fault – The sensor is reading incorrect temperatures.
13. Error Code 33: Outgoing Water Temperature Sensor Fault – The water temperature sensor is malfunctioning.
14. Error Code 34: Combustion Air Temperature Sensor Fault – The sensor is reading incorrect air temperatures.
15. Error Code 52: Modulating Solenoid Valve Fault – The solenoid valve controlling gas flow is malfunctioning.
16. Error Code 61: Fan Motor Error – The fan motor is not operating properly.
17. Error Code 71: Gas Valve Drive Circuit Fault – The gas valve is not being controlled properly.
18. Error Code 72: Flame Sensing Fault – The flame sensor is not detecting a flame.
19. Error Code 79: Heat Exchanger Fault – There is an issue with the heat exchanger’s operation.
20. Error Code LC: Scale Build-up Detected – The system has detected limescale build-up in the heat exchanger.

Rheem HVAC Error Codes

Rheem is one of the most trusted HVAC brands globally, especially known for water heaters. Here are 20 common Rheem error codes:

1. Code 00: No Fault Detected – System operating normally.
2. Code 01: Ignition Failure – The system is unable to ignite after several attempts.
3. Code 02: Flame Failure – The flame is lost during operation.
4. Code 03: Combustion Error – There’s an issue with the combustion process.
5. Code 04: Low Water Pressure – The system pressure is too low for operation.
6. Code 05: High Water Pressure – The system pressure is too high.
7. Code 06: Thermostat Error – The thermostat is malfunctioning.
8. Code 07: Fan Motor Error – The fan motor is not functioning properly.
9. Code 08: Over Temperature Warning – The system is shutting down due to high temperatures.
10. Code 09: Ventilation Error – The vent system is blocked or malfunctioning.
11. Code 10: Water Flow Sensor Error – The system is not detecting adequate water flow.
12. Code 11: Gas Valve Error – The gas valve is not opening or closing properly.
13. Code 12: Communication Error – Communication between components has failed.
14. Code 13: High Pressure Switch Open – The system pressure is too high and has tripped the switch.
15. Code 14: Low Pressure Switch Open – The system pressure is too low and has tripped the switch.
16. Code 15: Defrost Mode Error – The defrost cycle is malfunctioning.
17. Code 16: Condensate Pump Failure – The pump responsible for draining condensation has failed.
18. Code 17: Flame Sensor Failure – The flame sensor is not detecting a flame.
19. Code 18: Heat Exchanger Overheat – The heat exchanger temperature is too high.
20. Code 19: Compressor Overload – The compressor is drawing too much power.

Daikin HVAC Error Codes

Daikin is a leader in energy-efficient HVAC systems, and like all systems, it can encounter errors. Here are 20 common Daikin error codes:

1. U0: Low Refrigerant Charge – The system is detecting a refrigerant shortage.
2. U1: Reverse Phase – The power phase wiring is incorrect.
3. U2: Undervoltage – The system is detecting low voltage in the power supply.
4. U3: Malfunction in Start-up – There was an issue during system start-up.
5. U4: Communication Error – Communication between the indoor and outdoor units is lost.
6. U5: Indoor-Outdoor Communication Error – Communication between indoor and outdoor units is failing.
7. A0: External Protection Device Activated – External safety devices have shut down the system.
8. A1: PCB Malfunction – The printed circuit board (PCB) has malfunctioned.
9. A3: Drain Pump Malfunction – The condensate drain pump is malfunctioning.
10. A5: High Pressure Protection – The high-pressure switch is open due to excessive pressure.
11. A6: Fan Motor Malfunction – The fan motor is not operating.
12. A7: Swing Motor Malfunction – The swing motor is malfunctioning in ducted systems.
13. A9: Outdoor Coil Sensor Malfunction – The outdoor coil sensor has failed.
14. C4: Heat Exchanger Sensor Fault – The heat exchanger sensor is malfunctioning.
15. E1: Compressor Overcurrent – The compressor is drawing excessive current.
16. E5: Overload Protection – The system is shutting down due to overload.
17. E6: Compressor Motor Lock – The compressor is locked.
18. E7: Outdoor Fan Motor Malfunction – The outdoor fan motor is not working.
19. E8: High Discharge Pressure – The system pressure is too high.
20. E9: Low Discharge Pressure – The system pressure is too low.

Bryant HVAC Error Codes

Bryant HVAC systems offer great reliability, but they can still encounter issues. Here are 20 common Bryant error codes:

1. Code 31: Pressure Switch Fault – The pressure switch is not closing.
2. Code 32: Low Pressure Lockout – Low refrigerant levels have triggered a system shutdown.
3. Code 33: Limit Switch Fault – The high limit switch has tripped.
4. Code 34: Ignition Failure – The system is unable to ignite.
5. Code 35: Flame Sensor Failure – The flame sensor is not detecting a flame.
6. Code 36: Inducer Motor Error – The inducer motor is not operating.
7. Code 37: Gas Valve Circuit Open – There is a fault in the gas valve circuit.
8. Code 38: Compressor Overload – The compressor is drawing excessive current.
9. Code 39: High Pressure Lockout – The system pressure is too high.
10. Code 40: Low Pressure Lockout – The refrigerant pressure is too low.
11. Code 41: Blower Motor Error – The blower motor is malfunctioning.
12. Code 42: Heat Exchanger Overheat – The heat exchanger is overheating.
13. Code 43: Outdoor Coil Sensor Fault – The outdoor coil sensor has failed.
14. Code 44: Indoor Coil Sensor Fault – The indoor coil sensor is malfunctioning.
15. Code 45: High Discharge Temperature – The discharge temperature is too high.
16. Code 46: Low Discharge Temperature – The discharge temperature is too low.
17. Code 47: Low Voltage Lockout – The system voltage is too low for operation.
18. Code 48: Defrost Error – The defrost cycle is not functioning properly.
19. Code 49: Condensate Pump Error – The condensate pump is malfunctioning.
20. Code 50: Thermostat Communication Error – The thermostat is not communicating with the control board.

Amana HVAC Error Codes

Amana is known for its high-efficiency HVAC systems. Here are 20 common Amana error codes:

1. E0: No Fault Detected – The system is operating normally.
2. E1: Ignition Lockout – The system has locked out after failed ignition attempts.
3. E2: Flame Sensor Failure – The flame sensor is not detecting a flame.
4. E3: Pressure Switch Failure – The pressure switch is not closing.
5. E4: High Limit Switch Open – The limit switch has tripped due to overheating.
6. E5: Low Limit Switch Open – The system is shutting down due to low temperature.
7. E6: Blower Motor Error – The blower motor is not operating correctly.
8. E7: Vent Pressure Fault – The system is detecting incorrect vent pressure.
9. E8: Over Temperature Warning – The system temperature is too high.
10. E9: Defrost Cycle Error – The system encountered an issue during the defrost cycle.
11. EA: Gas Valve Malfunction – The gas valve is not opening or closing properly.
12. EB: Fan Speed Error – The fan is not running at the correct speed.
13. EC: Compressor Overload – The compressor is drawing excessive power.
14. ED: Refrigerant Leak Detected – A leak in the refrigerant system has been detected.
15. EE: Coil Sensor Fault – The coil temperature sensor is malfunctioning.
16. EF: Communication Failure – The control board is not communicating with system components.
17. EG: Heat Exchanger Overheat – The heat exchanger temperature is too high.
18. EH: Outdoor Coil Freeze – The outdoor coil has frozen.
19. EI: Indoor Coil Freeze – The indoor coil has frozen.
20. EJ: Defrost Sensor Error – The sensor used for the defrost cycle has failed.

Ruud HVAC Error Codes

Ruud is a popular choice for residential and Commercial HVAC systems. Here are 20 common Ruud error codes:

1. 01: Ignition Failure – The system failed to ignite after several attempts.
2. 02: Flame Sensor Failure – The sensor is not detecting a flame during operation.
3. 03: Pressure Switch Fault – The pressure switch is stuck open or closed.
4. 04: High Limit Switch Open – The high limit switch has tripped due to overheating.
5. 05: Low Pressure Switch Open – The system is shutting down due to low refrigerant pressure.
6. 06: Fan Motor Error – The fan motor is not operating properly.
7. 07: Compressor Overload – The compressor is drawing too much power.
8. 08: Gas Valve Fault – The gas valve is not opening or closing correctly.
9. 09: Thermostat Error – The thermostat is malfunctioning.
10. 10: Low Voltage Lockout – The system voltage is too low to operate.
11. 11: High Pressure Lockout – The refrigerant pressure is too high.
12. 12: Defrost Error – The defrost cycle is malfunctioning.
13. 13: Condensate Pump Failure – The condensate pump is not working.
14. 14: Coil Sensor Error – The sensor is reading incorrect temperatures.
15. 15: Refrigerant Leak Detected – A refrigerant leak has been detected in the system.
16. 16: High Discharge Temperature – The system discharge temperature is too high.
17. 17: Low Discharge Temperature – The system discharge temperature is too low.
18. 18: Heat Exchanger Overheat – The heat exchanger is overheating due to poor airflow.
19. 19: Low Refrigerant – The system is low on refrigerant and needs a recharge.
20. 20: Blower Motor Error – The blower motor is malfunctioning or running at incorrect speeds.

York HVAC Error Codes

York systems are widely known for their efficient HVAC systems, but like all systems, they can encounter problems. Here are 20 common York error codes:

1. E0: System Operating Normally – No faults detected.
2. E1: Ignition Failure – The system has failed to ignite after multiple attempts.
3. E2: Flame Sensor Error – The flame sensor is not detecting a flame.
4. E3: Pressure Switch Error – The pressure switch is stuck open or closed.
5. E4: Limit Switch Error – The limit switch has tripped due to high temperatures.
6. E5: Blower Motor Error – The blower motor is not running properly.
7. E6: High Pressure Lockout – The refrigerant pressure is too high.
8. E7: Low Pressure Lockout – The refrigerant pressure is too low.
9. E8: Defrost Mode Error – The system has encountered a problem during the defrost cycle.
10. E9: Gas Valve Circuit Open – There is a fault in the gas valve circuit.
11. EA: Fan Motor Failure – The fan motor is not functioning.
12. EB: Heat Exchanger Overheat – The heat exchanger temperature is too high.
13. EC: Low Voltage Lockout – The system voltage is too low to operate.
14. ED: High Voltage Lockout – The system voltage is too high for safe operation.
15. EE: Outdoor Coil Sensor Error – The sensor on the outdoor coil is malfunctioning.
16. EF: Indoor Coil Sensor Error – The sensor on the indoor coil is malfunctioning.
17. EG: Refrigerant Leak Detected – A refrigerant leak has been detected.
18. EH: Compressor Overload – The compressor is drawing excessive power.
19. EI: Condensate Pump Failure – The condensate pump is not working properly.
20. EJ: Heat Exchanger Cracked – The heat exchanger may be cracked or damaged.

Navien HVAC Error Codes

Navien specializes in tankless water heaters and high-efficiency boilers. Here are 20 common Navien error codes:

1. E001: Ignition Failure – The system failed to ignite after several attempts.
2. E002: Flame Loss – The flame is extinguished during operation.
3. E003: Water Flow Sensor Error – The system is not detecting adequate water flow.
4. E004: High Water Pressure – The system is detecting excessively high water pressure.
5. E005: Over Temperature Error – The water temperature is too high.
6. E006: Low Water Pressure – The system is detecting low water pressure.
7. E007: Vent Blockage – The venting system is blocked or restricted.
8. E008: Heat Exchanger Overheat – The heat exchanger temperature is too high.
9. E009: Exhaust Temperature Error – The exhaust temperature is outside normal ranges.
10. E010: Outdoor Sensor Error – The outdoor temperature sensor has malfunctioned.
11. E011: Gas Supply Error – The system is not detecting a sufficient gas supply.
12. E012: Combustion Air Blockage – The air supply for combustion is blocked or restricted.
13. E013: Thermostat Communication Error – The thermostat is not communicating with the control board.
14. E014: Blower Motor Error – The blower motor is not operating correctly.
15. E015: Condensate Drain Blockage – The condensate drain is blocked.
16. E016: Flame Sensor Error – The flame sensor is not detecting a flame.
17. E017: Pump Failure – The pump responsible for circulating water is not working.
18. E018: Low Voltage Error – The system voltage is too low for operation.
19. E019: High Voltage Error – The system voltage is too high for safe operation.
20. E020: Compressor Overload – The compressor is drawing excessive power.

Conclusion

Understanding the error codes for major HVAC brands like Lennox, Trane, Carrier, Goodman, Viessmann, Rinnai, Rheem, Daikin, Bryant, Amana, Ruud, York, and Navien is essential for diagnosing and troubleshooting issues with your system. Whether it’s a minor sensor malfunction or a major component failure, these codes help technicians and homeowners pinpoint the problem quickly.

At HeatLand Heating & Cooling, we specialize in servicing all of these brands, ensuring that any error code, whether simple or complex, is resolved quickly and efficiently. If you encounter any of these error codes or if your system is experiencing problems, don’t hesitate to contact us for professional HVAC support.

For service, repairs, and installations, reach out to HeatLand Heating & Cooling at 604-330-3812 or email us at info@HeatLand.ca We proudly serve customers throughout the Greater Vancouver region, including Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, Langley, Delta, and beyond.