In this article, we will address the F2 and F3 error codes commonly found in air conditioning systems. We will explain their meaning, possible causes, and the steps to resolve them properly.
Temperature Sensors: Key to Diagnosis
Most air conditioning systems include several temperature sensors that are essential for proper operation:
- Evaporator or pipe temperature sensor: prevents freezing of this part.
- Indoor ambient temperature sensor: measures the temperature of the conditioned space.
With the advent of inverter systems and the need to optimize power consumption, additional sensors have been introduced for more precise control, such as:
- Outdoor temperature sensor: located in the condenser unit, it measures the temperature of the outdoor air.
- Condenser outlet sensor: calculates the subcooling of the refrigerant.
- Compressor discharge sensor: measures the temperature and pressure of the refrigerant gas at the compressor outlet.
The outdoor unit’s control board regulates these sensors, sending and receiving signals to ensure the efficient operation of the system.
What Do the F2 and F3 Errors Mean?
The F2 and F3 error codes are associated with specific sensor issues:
- F2: Problems with the sensor located in the condenser pipe.
- F3: Problems with the sensor located in the compressor discharge pipe.
Steps to Resolve F2 and F3 Errors
- Restart the Unit
- Turn off the air conditioner for several minutes and turn it back on. Check if the error persists.
- Visual Inspection of the Affected Sensor
- Locate the sensor associated with the error code.
- Ensure the sensor is securely positioned and free of moisture. Clean it with a dry cloth.
- Check the condition of the wiring and connections to the outdoor control board.
- Electrical Testing of the Sensor
- Disconnect the sensor and use a multimeter set to the kilo-ohm scale to measure its resistance.
- If the reading is zero or infinite, replace the sensor.
- If the manufacturer’s reference values are unavailable, rub the sensor with your hands and observe if the resistance value decreases. If it does not, the sensor is defective.
- Check the Sensor’s Power Supply
- Connect the sensor and turn the unit on.
- Use the multimeter on the DC voltage scale to measure the sensor’s power supply. The voltage should be close to 2.5 V.
- If the power supply is incorrect, the problem could be in the outdoor unit’s control board.