Meaning: The indoor unit has an EEPROM (Electrically Erasable Programmable Read-Only Memory) parameter error.

Detailed Solutions:

• Power off the unit and restart it to reset the EEPROM parameters.
• If the issue persists, consult the system manual to verify EEPROM settings.
• Consider contacting an HVAC professional to reprogram or replace the EEPROM chip.

Meaning: There is a communication error between the indoor and outdoor unit.

Detailed Solutions:

• For new installations: Shut down the unit immediately to prevent damage.
• Verify wiring and ensure there is no damage or loose connections.
• Check for potential interference from high-frequency electronics near the line set (e.g., computers, flat screens, microwaves).
• For existing installations: This issue may indicate a board failure. Conduct AC and DC electrical tests to confirm the problem.

Meaning: There is a zero-crossing signal detection error.

Detailed Solutions:

• Check the power supply to ensure it is stable and within the recommended range.
• Inspect the indoor unit's control board for potential faults.
• Reset the system and monitor for recurring issues.

Meaning: The indoor fan speed has been out of control.

Detailed Solutions:

• Ensure the fan motor is securely connected and operational.
• Check for any obstructions or debris in the fan blades that might affect performance.
• Inspect the control board for errors or loose connections.
• Replace the fan motor if it is found to be faulty.

Meaning: The indoor room temperature sensor (T1) is in open circuit or has short-circuited. The T1 sensor connected to the indoor board is loose or has gone out.

Detailed Solutions:

• Inspect the T1 sensor for secure connections to the indoor board.
• Replace the sensor if it shows signs of damage or malfunction.
• Ensure the indoor board is functioning correctly to communicate with the sensor.

Meaning: The evaporator coil temperature sensor (T2) is in open circuit or has short-circuited. The T2 sensor connected to the indoor board is loose or has gone out.

Detailed Solutions:

• Ensure the T2 sensor is securely connected to the indoor board.
• Inspect the sensor for physical damage and replace if necessary.
• Clean the evaporator coil to ensure no interference with sensor functionality.

Meaning: The system has detected a potential refrigerant leak.

Detailed Solutions:

• Perform a thorough soapy water test along the refrigerant lines to identify potential leaks.
• Contact an HVAC professional to conduct a leak detection test if no visible leaks are found.
• Repair any identified leaks and recharge the refrigerant to appropriate levels.

Meaning: There is a communication error between the indoor PCB and display board.

Detailed Solutions:

• Inspect the wiring connections between the PCB and display board to ensure they are secure.
• Restart the system to reset communication protocols.
• If the issue persists, consider replacing the indoor PCB or display board.

Meaning: The outdoor unit has detected loose wiring, incorrect voltage, or a board issue.

Detailed Solutions:

• Verify all wiring connections to the outdoor unit are secure and properly connected.
• Measure the incoming voltage to ensure it matches the system's requirements.
• Inspect the outdoor control board for signs of damage or malfunction and replace if necessary.

Meaning: The outdoor ambient temperature sensor (T4) is in open circuit or has short-circuited.

Detailed Solutions:

• Inspect the T4 sensor connection to the outdoor board for loose or disconnected wiring.
• Replace the sensor if it shows signs of damage or malfunction.
• Ensure proper placement of the sensor to accurately measure outdoor ambient temperature.

Meaning: The condenser coil temperature sensor (T3) is in open circuit or has short-circuited.

Detailed Solutions:

• Verify the T3 sensor connection to the outdoor control board.
• Inspect the condenser coil for any buildup of debris that may interfere with the sensor.
• Replace the T3 sensor if it is damaged or malfunctioning.

Meaning: The compressor discharge temperature sensor (T5/TP) is in open circuit or has short-circuited.

Detailed Solutions:

• Ensure the T5/TP sensor is securely connected to the outdoor board.
• Inspect the sensor for physical damage or signs of malfunction and replace if needed.
• Check for proper airflow around the compressor to avoid overheating issues.

Meaning: The outdoor unit has encountered an EEPROM (Electrically Erasable Programmable Read-Only Memory) parameter error.

Detailed Solutions:

• Reset the system by powering it off for a few minutes and then restarting.
• Check the outdoor unit’s control board for faults and verify all connections.
• Consult a qualified HVAC technician to reprogram or replace the EEPROM if the error persists.

Meaning: The outdoor fan speed is out of the acceptable range.

Detailed Solutions:

• Inspect the outdoor fan motor and blades for obstructions, debris, or physical damage.
• Check the fan speed sensor wiring for secure connections and proper functionality.
• Replace the fan motor or speed sensor if any faults are detected.

Meaning: The evaporator coil outlet temperature sensor (T2B) is in open circuit or has short-circuited. This is commonly seen in multi-zone systems.

Detailed Solutions:

• Inspect the T2B sensor cable for loose or disconnected wiring during shipping or due to vibration.
• Shut down the unit and turn off the breaker before removing the panels.
• Locate the white Molex plug, usually near the circuit board or terminal block, and ensure it is securely connected.
• Reassemble the unit and restart to test functionality.

Meaning: Indicates a problem with the Intelligent Power Module (IPM) or excessive current in the IGBT.

Detailed Solutions:

• Inspect the power supply for stability and ensure the voltage matches system requirements.
• Check the outdoor unit control board for damage or loose connections.
• Replace the IPM module if necessary and consult an HVAC professional for advanced diagnostics.

Meaning: The system has detected voltage levels outside the acceptable range.

Detailed Solutions:

• Verify the incoming voltage using a multimeter to ensure it falls within the specified range.
• Install a voltage stabilizer or surge protector if the power supply is unstable.
• Inspect all electrical connections for secure and proper installation.

Meaning: The system has detected high temperatures in the IPM module or excessive refrigerant pressure.

Detailed Solutions:

• Ensure all line set connections are tightened properly with no threads showing.
• Verify that service valves are fully open and locked in place.
• Inspect the condenser for adequate ventilation and clear any obstructions around the outdoor unit.

Meaning: The system has detected low refrigerant pressure.

Detailed Solutions:

• Inspect all line set connections, including air handlers, condensers, and extension couplers, to ensure they are fully tightened.
• Verify that service valves are fully open and secured to the locking ring.
• If the system is a multi-zone unit, check that the king valves on the vertical lines are fully open.
• Check refrigerant pressure levels and recharge the system if necessary.

Meaning: For Advantage systems, this error indicates that the outdoor ambient temperature is too low.

Detailed Solutions:

• If outdoor temperatures are below -13°F, allow the system to defrost naturally.
• Inspect the outdoor temperature sensor for damage or ice buildup.
• Check for a dirty coil or low refrigerant charge and resolve as needed.

Meaning: This error is generally related to restrictions in the system or line set connections.

Detailed Solutions:

• Ensure all line set connections are tightened properly, with no threads visible.
• Verify that service valves are fully open and locked in place.
• If the system is multi-zone, check that the king valves on vertical lines are fully open.
• Inspect the inverter drive for signs of failure or overheating.

Meaning: The system has detected an overload of current.

Detailed Solutions:

• Inspect the power supply for stability and ensure it matches the system's voltage requirements.
• Check all electrical connections for secure and proper installation.
• Consult an HVAC technician to inspect and replace components, such as the compressor or control board, if necessary.

Meaning: The discharge temperature sensor is malfunctioning, usually indicating a refrigerant-related issue.

Detailed Solutions:

• Inspect all line set connections and ensure they are fully tightened with no visible threads.
• Check for leaks or oil residue on fittings, which could indicate a refrigerant issue.
• If the system is a multi-zone unit, confirm that the king valves are open and properly seated.
• Replace the discharge temperature sensor if it is damaged or malfunctioning.

Meaning: The USB Smart Controller module has not been detected.

Detailed Solutions:

• Verify that the USB Smart Controller module is securely connected to the unit.
• Inspect the USB port for any debris or physical damage that could interfere with connectivity.
• Replace the USB Smart Controller module if it is not functioning correctly.

Meaning: The outdoor temperature is too low, causing the condenser to shut off for safety reasons.

Detailed Solutions:

• Allow the system to automatically resume operation when the temperature rises to an acceptable level.
• If this error persists in warmer conditions, inspect the outdoor ambient temperature sensor for faults.
• Ensure the system is installed in a location where it can operate within its specified temperature range.

Meaning: The indoor unit modes are in conflict, with one unit attempting to heat while another is attempting to cool.

Detailed Solutions:

• Switch all air handlers to the same mode (cooling, heating, or auto) to resolve the conflict.
• Avoid using auto mode on multi-zone systems to prevent mode mismatches.
• If the issue persists, reset the system by turning it off and on again.

Meaning: This error indicates a bad wiring configuration at the unit.

Detailed Solutions:

• Verify the wiring configuration matches the manufacturer's specifications, especially at the condenser and air handler.
• Common mistakes include swapping wires 2 and 3; confirm their proper placement.
• Inspect the wiring for damage or loose connections, and replace wires if necessary.

Meaning: The system has detected a low-pressure restriction or that the low-pressure sensor is disconnected.

Detailed Solutions:

• Inspect all line set connections at the air handlers, condenser, and extension couplers to ensure they are fully tightened with no threads showing.
• Verify that service valves are fully open and secured to the locking ring.
• If the system is a multi-zone unit, ensure the king valves on the vertical lines are fully open.
• Check the low-pressure sensor wiring for proper connection and replace if necessary.

Meaning: Indicates that a minor adjustment in the set temperature is required.

Detailed Solutions:

• Raise or lower the set temperature by a few degrees and monitor the system's response.
• Ensure the thermostat is functioning correctly and not obstructed by external factors, such as direct sunlight or drafts.

Meaning: The unit is currently running in defrost mode at the condenser to remove ice buildup.

Detailed Solutions:

• Allow the unit to complete the defrost cycle; it will resume normal operation automatically.
• If the defrost mode activates frequently, inspect the outdoor coil for cleanliness and airflow obstructions.
• Verify that the defrost sensor is functioning correctly and replace it if necessary.

Meaning: The unit is currently running in freeze protection mode to prevent freezing in the system.

Detailed Solutions:

• Allow the system to continue running in freeze protection mode; this is a normal operating feature under specific conditions.
• Ensure the area around the outdoor unit is free from obstructions and debris to optimize airflow.
• If the freeze protection mode engages frequently, inspect the refrigerant levels and system settings to ensure proper operation.

Meaning: The unit is currently running in forced cooling mode, often used during specific maintenance or diagnostic procedures.

Detailed Solutions:

• Allow the system to complete its forced cooling cycle if it was intentionally initiated.
• Check system settings to ensure forced cooling was not accidentally activated.
• If the system remains stuck in forced cooling mode, reset the unit by turning off the power and restarting.