Common faults
Split System Not Cooling, Not Heating or Leaking? Common Faults Explained
What it usually means when a split system stops cooling or heating, drips water, makes a new noise or shows an error code, safe checks, and when to book a repair.
Updated 13 September 2026 by the Macedon Ranges Gas & Air team
The safe checks first
- Mode and temperature. Is the remote set to cool (or heat), not fan or dry, with a set temperature the unit can reach? A remote left in the wrong mode is a common call.
- Filters. The indoor unit’s filters slide out from the front panel on most units. If they are clogged with dust, clean them as the manual describes. Blocked filters cause weak airflow, poor cooling and can lead to icing.
- Power. Is the isolator at the outdoor unit on, and the circuit breaker on at the switchboard?
- The outdoor unit. Is it running when the system is on, and is it clear of leaves, boxes and plant growth?
Do not open the outdoor unit, touch refrigerant pipework or attempt electrical work.
Not cooling, or not heating
Dirty filters or a dirty indoor coil, a dirty outdoor coil, a fan that has stopped, a sensor fault, or low refrigerant from a leak. A system that has lost refrigerant needs the leak found and repaired by a licensed technician; topping it up without fixing the leak is not a repair.
Water dripping from the indoor unit
Almost always a blocked or kinked condensate drain, or occasionally an indoor unit that was installed without enough fall on the drain. Turn it off if it is dripping onto anything that matters and book it in.
Ice on the indoor unit or the pipes
Restricted airflow (filters, coil), low refrigerant or a fan problem. Turn the system off and let it thaw; running it iced up does not help.
New noises
Rattles from the outdoor unit are often a fan, a loose panel or debris. Gurgling or hissing can be refrigerant related. A grinding motor should be switched off.
Error code on the display
Most systems show a code or a flashing pattern when they detect a fault. Note it down; it tells our technician where to start.
What we do
We service and repair all major split system brands, whoever installed them, with a local technician and a broad range of common parts on the van. If a system is old and the repair is not economical, we say so and explain the replacement options. A yearly service keeps the filters, coils and drain clear and picks up small problems before they become a call-out.
Need it done?
Split System Repairs
Split system not cooling, heating, leaking or showing an error code? Our licensed technicians repair all major brands across the Macedon Ranges, price agreed first.
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Get in touch
Book a repair
Tell us what the system is doing. A photo of the controller or the unit helps, but is not needed.
Prefer to talk? Call 1300 369 400, monday to friday 8:00am to 5:00pm, Saturday 9:00am to 1:00pm.