Why a top-up-and-walk-away job is the wrong answer
A common "needs more gas" story on the Sunshine Coast is a system that was refilled twelve months ago and is empty again. That is no surprise: refrigerant is not used up in normal running, so a system that loses charge is leaking. Refilling it without finding the leak means paying for gas that will leave by the same hole within months. Beyond the wasted money, R32 and R410A are scheduled greenhouse gases under the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989. Australian Refrigeration Council (ARCtick) licensing does not permit anyone to knowingly recharge a leaking system; doing so risks a six-figure penalty for the licence holder and an unlicensed sub-contractor breach for everyone involved.
So the job should start with proper detection. It costs more on day one, but it finds the leak, and after the repair the regas should be the last thing you spend on that unit for years.
Stage one - recovery, pressure test, electronic sniffer
The first visit takes about 60 to 90 minutes on a typical home split system. The licensed technician connects to the service ports and recovers any refrigerant left in the system into a recovery cylinder, which is recorded under ARCtick rules. The system is then charged with dry nitrogen to about 4000 kPa, well above operating pressure, and shut in. A 30-minute hold shows whether there is a fast leak, while an ultrasonic detector and a soap-bubble pass check every visible flare joint, the indoor and outdoor coil headers and the service valves. Many leaks are found at this point.
Smaller leaks do not push out enough nitrogen to detect in one session. The next tool is an electronic refrigerant sniffer, a heated-diode sensor that picks up fluorocarbon molecules at parts-per-million levels, swept over every joint, the indoor coil face, the line set where it passes through walls and roof spaces, the outdoor coil and the service-port cores. More leaks show up here.
Stage two - UV dye and the patient wait
The rest, the slow weeps and pinholes that only open when the system runs hot, need UV dye. A fluorescent dye goes in through the service port, enough fresh refrigerant is weighed in to restore the nameplate charge, and the system runs normally for 10 to 14 days while the dye travels with the refrigerant to wherever it escapes. The second visit takes 30 to 45 minutes: a UV torch over every joint and coil in a darkened service position, where the dye glows bright yellow-green at the leak.
Where the leaks actually are on Sunshine Coast aircons
Around Maroochydore, Mooloolaba, Caloundra, Coolum and the hinterland, the leak points are fairly consistent:
Flare joints at the outdoor isolation valves
The flare nut joining the line set to the outdoor service valve sits out in the weather. Twelve years of thermal cycling, fan vibration and, on coastal homes, chloride attack on the brass nut eventually break the seal at a microscopic level. Most are dry to the touch because the gas escapes invisibly. The repair is simple: recover the gas, cut off the old flare, form a fresh 45-degree flare torqued to the manufacturer's spec, then evacuate and recharge. Expect around $120 to $180 for the labour, plus the regas.
Indoor coil pinhole - formic acid corrosion
Formicary corrosion happens when trace volatile organic compounds (household cleaning sprays, formaldehyde from new furniture, vinegar) mix with condensate on the copper coil tubes and eat tiny crater-shaped pits until the tube wall gives way. The fix is a new coil. On a five-year-old unit that can be worth doing ($800 to $1400 fitted); on a twelve-year-old system it usually points toward replacement.
Schrader service valve cores
Each service port holds a small spring-loaded valve core, much like the valve in a car tyre. After thousands of pressure cycles the rubber seal weeps. Swapping the core takes about five minutes with a specialist tool that works under residual pressure, but the regas costs more than the part: about $80 labour plus the regas.
Copper line-set rub-through
Where the refrigerant lines pass through a wall, cross a roof void or rest against a vibrating outdoor unit, years of low-level vibration can wear through the copper. The repair is a replacement section with a flare or brazed join, about $180 to $320 labour depending on access.
Outdoor coil pinhole
Another coastal fault: chloride corrosion can pit a U-bend at the bottom of a condenser coil until it breaches. The only fix is a new coil, $900 to $1600 fitted depending on brand.
What an itemised quote should show
A leak job should be quoted in three lines: detection, repair and regas, each with its own cost for you to approve. If stage one finds nothing and you decide not to go on to the dye stage, you should only pay for stage one. If the repair does not make sense on an older system, you should hear that before any money changes hands: spending $1600 on a coil for a 12-year-old unit rarely beats a new install with a new warranty and better efficiency.
Service area & booking
Refrigerant leak detection enquiries are taken across the Sunshine Coast: Maroochydore, Mooloolaba, Buderim, Caloundra, Kawana, Sippy Downs, Nambour, Noosa, Coolum and the hinterland from Maleny to Yandina. Use the quote form or email quotes@sunshinecoastairconservice.com.au with your suburb, the brand and a short description of the symptom (warm air, ice on the suction line, running constantly without cooling).
FAQs about refrigerant leaks on Sunshine Coast aircons
Why won't a technician just top up the gas?
Because it is illegal. Refrigerants like R32 and R410A are scheduled greenhouse gases under the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989, and ARCtick refrigerant-handling licensing does not permit a knowing top-up of a leaking system. The leak has to be found and fixed first. A top-up without the repair also wastes your money: the gas you paid for is already on its way out, and the same fault will be back within months.
How long does two-stage leak detection take?
The first visit is 60 to 90 minutes: the technician recovers the remaining gas, pressure-tests with dry nitrogen to 4000 kPa, runs an electronic sniffer over every joint and both coils, and injects UV dye if the sniffer finds nothing. The system then runs for 10 to 14 days while the dye moves to the leak. The second visit is 30 to 45 minutes: a UV torch sweep of every joint and coil, the leak located and the repair quoted. It is slower than a one-visit check, but it is the only reliable way to find a slow weep a single sniffer pass misses.
Where are the leaks usually on a Sunshine Coast aircon?
Most often at the flare joints on the outdoor isolation valves (vibration plus salt corrosion on the brass nut), as indoor coil pinholes from formic-acid corrosion (more common within a kilometre of the coast), at Schrader service valve cores that have weeped past their seal, where the copper line set rubs through at a wall or roof crossing, and as outdoor coil pinholes from coastal exposure. Flare-joint and Schrader leaks are cheap to fix; a coil pinhole usually means a new coil, which on an older unit points toward replacing the system.
What should a regas quote with the leak found look like?
Three separate lines, so you can see what each part costs. Leak detection: usually $280 to $380 for the two-stage process, including nitrogen, dye and labour. The repair: from $120 for a re-flared joint to $1400 or more for an indoor coil, with the parts price shown. The regas: vacuum down to 500 microns, hold the vacuum to prove the system is tight, then weigh in fresh refrigerant to the nameplate charge, usually $280 to $420 depending on system size. A typical flare-joint leak comes to about $700 to $900 all up. If the repair would cost more than half a new unit on a system over 10 years old, a fair technician will say so and suggest replacement.