Air Conditioning in Sydney
49/3 Hornsey street, Rozelle, NSW, 2039, Australia

By Victor /

Typical Error Codes and their explanations:

  • Outdoor 0-9
  • Indoor E2-E9
  • Chronological Order

Some examples of general Outdoor/Indoor AC codes are 0 (heating mode) and 1 (cooling Mode). Other error codes you may stumble upon are 4 which is a low speed and will flash every thirty seconds or so. Others are 2 being that the compressor has been running for more than twenty minutes. The majority, if not all error codes you’ll experience will come from indoor AC units. Those are, and not limited to the following:


E2-E9 Error Codes

These vary upon unit obviously

  • Fault indoor coil out sensor
  • Fault room sensor(s) (open or closed circuit)
  • Fault indoor coil sensor (open or closed circuit)
  • Communication
  • Faulty Discharge temp
  • Faulty outdoor Coil Sensor
  • High/Low Pressure Sensor

That last one (E9) is for newer models.
Now that we have a general explanation, let’s dig a bit deeper into this contained cultivated sensation.



Air Conditioning certified specialist in Sydney, Australia. Victor is a highly skilled and certified air conditioning specialist based in Sydney, Australia. With over 15 years of experience in the HVAC industry, John has become an expert in the installation, maintenance, and repair of various air conditioning systems, including split systems, ducted systems, and multi-head units. John began his journey in the HVAC field after completing a comprehensive apprenticeship program and obtaining his trade certificate. He then worked with several reputable air conditioning companies in Sydney, honing his skills and gaining valuable insights into the industry. In 2010, Victor received his Air Conditioning and Refrigeration Council (ARC) certification, further solidifying his status as a trusted professional in the field.