Aircon regas in Sydney: the leak repaired first, then recharged properly

The gas in a split system circulates in a closed circuit, round and round between the two units, for the life of the system. Nothing burns it off. So when a technician says yours is low, the real news is that it has a hole somewhere, and the useful question is where.

The usual suspects are the flare nuts where the pipes join each unit, a brazed joint that has cracked with vibration, copper that has worn against a bracket or a wall, and, in this city, a coil eaten through by salt. Recharging without finding which one simply refills a leaking circuit, and you pay for that gas a second time when it runs out again. We locate the leak first and show it to you. If it sits in a part that is not worth fixing, you hear that before a cent is spent.

Near the beaches, from the eastern suburbs to the Northern Beaches and the Sutherland Shire, salt in the air settles on the outdoor coil. The aluminium fins and copper tubes corrode slowly until a pinhole opens and gas escapes. A corroded coil can sometimes be repaired, but when the damage is widespread, a new outdoor coil or a new system is the honest answer, and you hear that before any money is spent. Our coastal air conditioning guide covers the simple maintenance that slows it down.

A system that is short of refrigerant loses its ability to pull moisture out of the air before it stops cooling outright. In Sydney that shows up as a room that is cool-ish but clammy, or a dry mode that no longer feels dry. It is an early sign worth acting on, because a system running short works harder and wears the compressor.

With the leak repaired, the circuit is filled with dry nitrogen and left under pressure to prove the repair holds. Then a vacuum pump draws out the nitrogen, air and moisture. Moisture matters more than people expect in a humid city like Sydney: left inside, it mixes with the oil and attacks the compressor from within. Only then does the refrigerant go back in, weighed to the charge printed on the unit plate, and the system is run in cooling and in heating while pressures and temperatures are read. Every step is carried out by licensed refrigeration technicians, and any gas recovered from the system is captured, never released.

Four things decide what a regas costs: where the leak is and how hard it is to reach, what the repair needs, which refrigerant the system runs on, and how many kilograms it holds. A unit on a third-floor balcony with a leak at an easy flare joint is a very different job from a corroded coil on a rooftop plant deck. That is why the technician inspects and quotes before any work, and you approve first.

The refrigerant matters too. Current systems run on R32 or R410A. Units from the early 2000s and before often run on R22, which is no longer made and is hard to get, so on those a big leak usually tips the decision towards a new system. Our split system regas cost guide goes through each factor.