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7 July 2026
Why Is There Water Around My Outdoor Air Conditioner?
8 July 2026
If you’ve noticed steam or mist coming from your outdoor air conditioning unit while it’s running in heating mode, don’t panic.
This is one of the most common questions we receive during winter, and in most cases, it’s completely normal.
Why is my outdoor unit steaming?
When your reverse cycle air conditioner is heating your home, the outdoor unit is working hard to extract heat from the outside air.
On cold winter days, frost can naturally form on the outdoor coil. To maintain efficient operation, your system will automatically enter what’s known as a defrost cycle.
During this process, the frost is melted away so your system can continue heating your home efficiently.
As this happens, you’ll often notice steam or mist rising from the outdoor unit.
Although it may look unusual, it’s simply warm air meeting cold outdoor air and is a normal part of your air conditioner’s operation.
What is a defrost cycle?
A defrost cycle is an automatic feature built into modern reverse cycle air conditioners.
Its purpose is to remove frost that builds up on the outdoor coil during colder weather.
Without this process, the frost would continue to build up, reducing the system’s efficiency and its ability to heat your home.
Your air conditioner manages this process automatically, so there’s nothing you need to do.
How long does the defrost cycle last?
Most defrost cycles only last a few minutes.
During this time you may notice:
- Steam or mist rising from the outdoor unit.
- The indoor heating may pause briefly.
- The outdoor fan may slow down or stop temporarily.
Once the cycle is complete, your system will automatically return to normal heating operation.
Is steaming a sign something is wrong?
In most cases, no.
If the steam only appears occasionally while your system is heating, it’s generally a sign that your air conditioner is operating exactly as designed.
Many homeowners mistake the steam for smoke, but it’s simply water vapour created during the defrost process.
When should I call a technician?
While occasional steaming is perfectly normal, you should contact a qualified technician if you notice:
- Your home isn’t heating properly.
- Your system is displaying an error code.
- The outdoor unit remains heavily iced over for an extended period.
- The system repeatedly enters defrost mode without returning to normal operation.
- You notice unusual noises or burning smells.
If you’re ever unsure whether your system is operating normally, it’s always worth having it checked by a qualified technician.
Keep Your System Running Efficiently
Regular servicing helps ensure your reverse cycle air conditioner continues to operate efficiently throughout winter.
During a maintenance service, our technicians inspect your system, check its overall performance, and identify any potential issues before they become costly repairs.
Keeping your system well maintained can improve efficiency, reduce running costs, and help extend the life of your air conditioner.
Need Advice?
If you’ve noticed steam coming from your outdoor unit and aren’t sure whether it’s normal, the friendly team at Morphett Air is here to help.
Whether you need expert advice, a maintenance service, or a new heating and cooling system, we’d be happy to assist.
