When a ducted system fails, the whole house feels it. There’s no backup unit in the bedroom to fall back on — one fault in the roof space and every room loses cooling at once. Ducted systems are also more complex than splits: alongside the compressor, fan coil and refrigeration circuit you have zone motors, dampers, duct runs, a central return air path and a zone controller, any of which can cause symptoms that look like a system failure but aren’t.
Our ARCtick-licensed technicians specialise in ducted reverse cycle repair across Brisbane and South East Queensland. We diagnose the whole system, not just the equipment — because a very large share of “my ducted isn’t cooling properly” call-outs turn out to be airflow problems: a collapsed duct in the roof space, a stuck zone damper, a return air filter that hasn’t been cleaned in three years, or a system that was never balanced correctly at installation.
Common ducted system faults
- Some rooms cool well, others barely at all
- No cooling or heating at all from any outlet
- Weak airflow across the entire system
- Zones not opening or closing, or stuck permanently open
- Wall controller blank, frozen, or showing an error code
- Water staining on the ceiling below the fan coil
- Loud rattling, humming or vibration from the roof space
- System short-cycling — running briefly then stopping
- Musty or dusty smell from the ceiling outlets
- Outdoor unit running constantly without reaching setpoint
- Circuit breaker tripping when the system starts
- Whistling or roaring noise at the diffusers
Benefits of Professional Ducted Repair
- Whole-system diagnosis covering refrigeration, electrical, controls, zoning and airflow — not just the fan coil.
- Airflow and duct expertise. We inspect the roof space, check duct integrity, measure airflow at each outlet and re-balance where required. Most general technicians skip this entirely.
- Zone and controller specialists. Damper motors, zone boards and proprietary controllers each have their own failure modes and diagnostic procedures.
- Safe roof space work with proper access equipment and awareness of Brisbane roof cavity temperatures, which routinely exceed 55°C in summer.
- Fixed quoted pricing approved before any work starts.
- Licensed and compliant — ARCtick refrigerant handling and QBCC-licensed electrical work.
- Honest repair-versus-replace advice, including whether existing ductwork can be retained if the equipment needs replacing, which dramatically changes the numbers.
- 12-month workmanship warranty on all repairs.
Our Ducted Repair Process
Phone triage
We take the brand, approximate age, controller type, error code and a description of which rooms or zones are affected. The pattern of which outlets work often points straight to the likely cause.
Controller and zone testing
We start at the controller: read fault codes and history, verify zone commands are being sent, and confirm each damper motor actually responds. A zone stuck closed is a very common cause of “that bedroom never cools”.
Fan coil inspection in the roof space
Fan coil accessed and inspected for coil fouling, return air filter condition, blower wheel buildup, drain pan and safety tray water, condensate line blockage, and vibration or mounting issues.
Refrigeration testing
Suction and discharge pressures read at the outdoor unit, superheat and subcooling calculated, and the temperature split measured across the fan coil to determine whether charge, compression or airflow is the limiting factor.
Electrical testing
Capacitors measured against rating, contactors, relays and zone board outputs tested, fan motor windings and running current checked, and terminals inspected for heat damage.
Duct and airflow inspection
We check the roof space for collapsed, kinked, crushed or disconnected duct, damaged insulation, leaking plenum joints and sagging runs, then measure airflow at the affected outlets.
Written quote and approval
Plain-English explanation of the fault, the cost, and where relevant the replacement comparison. Nothing proceeds until you approve it.
Repair and re-balance
Repair completed, then airflow re-measured and the system re-balanced so each room receives its designed share of air.
Testing and handover
Full cycle test in cooling and heating, every zone verified, drainage confirmed, written report and warranty issued, plus advice on preventing a recurrence.
Indicative Ducted Repair Costs
AUD including GST. Confirmed on site before work begins.
Repair | Indicative cost |
Service call and full system diagnosis | $150 – $280 |
Zone damper motor replacement | $300 – $700 |
Zone control board replacement | $500 – $1,200 |
Wall controller / touchscreen replacement | $350 – $900 |
Capacitor replacement | $200 – $380 |
Contactor or relay replacement | $220 – $450 |
Indoor fan motor (fan coil) | $700 – $1,600 |
Outdoor fan motor | $400 – $850 |
Condensate drain clearing and safety tray | $200 – $450 |
Condensate pump replacement | $400 – $750 |
Refrigerant leak detection | $250 – $550 |
Leak repair and recharge | $700 – $2,000 |
Control PCB replacement | $600 – $1,600 |
Reversing valve replacement | $900 – $1,900 |
Expansion valve replacement | $650 – $1,400 |
Compressor replacement (out of warranty) | $2,500 – $5,500 |
Collapsed or disconnected duct repair (per run) | $250 – $700 |
Duct replacement (per outlet run) | $300 – $800 |
Full system airflow re-balance | $350 – $700 |
Return air filter replacement | $80 – $250 |
For major failures on older systems — particularly compressors on units over ten years old — we always present the replacement comparison. Because existing ductwork can usually be retained, a ducted equipment replacement is often far less expensive than people expect.
Brands We Repair
ActronAir, Daikin, Mitsubishi Electric, Mitsubishi Heavy Industries, Fujitsu, Panasonic, Carrier, LG and Samsung, plus most other ducted brands in the Australian market.
Ducted repair is especially brand-dependent because the zone controllers and communication protocols are proprietary — an ActronAir zone system, a Daikin Airbase and a MyAir or MyPlace controller all diagnose completely differently. Our technicians hold the service data and diagnostic tools for these platforms, and we source genuine parts through Australian distributors. Tell us the controller brand when you book.
Service Areas
Ducted repairs across North Brisbane, South Brisbane, East Brisbane, West Brisbane, Brisbane CBD, Indooroopilly, Toowong, Chermside, Carindale, Sunnybank, Logan, Ipswich, Redlands and Moreton Bay.
Frequently Asked Questions
Why do some rooms cool well and others don’t?
This is the most common ducted complaint and it is usually airflow rather than a mechanical fault. Typical causes are a collapsed or kinked duct run in the roof space, a disconnected duct at the plenum or outlet, a stuck zone damper, a system that was never properly balanced at installation, or simply a heavily blocked return air filter starving the whole system. All are fixable.
Why is there water staining on my ceiling?
The condensate drain has blocked and the safety tray under the fan coil has overflowed. Brisbane humidity produces a lot of condensate and the drain lines clog with algae. Turn the system off immediately and book — left running, it will damage ceiling plasterboard and can reach light fittings.
One zone won’t turn on. Is the whole system faulty?
Usually not. It’s typically that zone’s damper motor, its wiring back to the zone board, or a failed output on the zone control board. The rest of the system is normally unaffected and the repair is relatively inexpensive.
My ducted runs constantly but never reaches the set temperature. Why?
Common causes are low refrigerant from a leak, a fouled outdoor condenser coil that can’t reject heat, a heavily blocked return air filter, too few zones open for the system’s minimum airflow, or a system that was undersized for the home in the first place. Diagnosis determines which.
How much does ducted repair typically cost?
Most repairs land between $250 and $900 including the call-out. Zone and control faults sit at the lower end, refrigeration work in the middle, and major component failures such as compressors and fan coil motors higher.
Should I repair or replace my ducted system?
Repair if the system is under about ten years old and the fault is a discrete component. Consider replacement if it is over 12–15 years old, uses R22 refrigerant, has had repeated failures, or needs a compressor. Importantly, existing ductwork, outlets and often the zoning can usually be reused, so a replacement is frequently in the $7,500–$15,000 range rather than the full cost of a new installation.
Can you repair the ductwork itself, or does it all need replacing?
Individual damaged runs can almost always be repaired or replaced in isolation. Full duct replacement is only warranted when insulation has degraded throughout, there’s widespread rodent damage, or the ducting is very old and undersized.
How quickly can you attend?
Same day or next day for most Brisbane suburbs. During summer heatwaves call early in the day. After-hours emergency attendance is available for total failures.
Is it safe for you to work in my roof space in summer?
Our technicians are trained and equipped for it, but Brisbane roof cavities exceed 55°C on hot afternoons. Where the work is extensive we may schedule roof space tasks for early morning, which is both safer and produces better workmanship.
How do I avoid ducted breakdowns?
Clean the return air filter every one to two months during heavy use — this single habit prevents a large share of the faults we attend. Add an annual professional service before summer covering coil cleaning, drain treatment, zone motor testing and airflow verification.
