For the climate’s sake, ensure your installer is ARC tick approved to handle refrigeration gas.
In this era of climate change, poor handling of ozone depleting refrigerant gases can add to the greenhouse effect.
The ARC tick can only be used by Australian Refrigeration Council approved installers. In fact, it is illegal to handle refrigerant gas without a license.
So for the planet’s sake, insist on an ARC tick approved installer.