Installing a Split System: The Electrical Side Before Summer

If a split system is going in before summer, the unit on the wall is only half the job. The other half is the circuit that feeds it, and the paperwork you should be holding when the installer leaves.

A split system is two trades in one job: refrigeration pipework and electrical work. Victoria licenses them separately, and it pays to know who is doing which part.

Two licences, and sometimes two businesses

A fact sheet from Energy Safe Victoria and the Victorian Building Authority sets out who can install a reverse cycle air conditioner. The installer needs a plumbing practitioner registration and a refrigerant handling licence, and either holds an electrician's licence or engages a Registered Electrical Contractor. Any electrical work must be completed by a Registered Electrical Contractor.

In practice that usually looks like one of two set ups:

• An installer who holds the plumbing registration and an electrical licence.
• An air conditioning installer who brings in a registered electrical contractor for the circuit and the connection.

Either is fine. What matters is that each part of the job is done by someone licensed for that part.

There is one narrow exception. The fact sheet says that where an old system is disconnected and replaced with a new one of equivalent power and current, in the same location, without altering the existing cables, the electrical work can be done by a restricted electrical licence holder in the refrigeration and air conditioning class. A first install, a bigger unit, or a new spot on the wall is not that job.

The circuit matters as much as the unit

Most of the electrical decisions happen at your switchboard, not on the wall.

Energy Safe Victoria's guidance on split system installations points to the wiring rules: equipment must be installed with any additional requirements in the manufacturer's instructions. If the manufacturer requires the air conditioner to be on a dedicated circuit, or protected by a residual current device, that must be followed. If the manufacturer specifies a cable size larger than the standards call for, that must be followed too.

So the questions worth asking at quote time are:

• Does this model need its own circuit, and is there room for one on the board?
• Will that circuit have safety switch protection?
• Where will the cable run between the board and the outdoor unit?

On an older board with ceramic fuses or no spare space, adding a circuit can turn into a conversation about the switchboard itself. Better to have that conversation at the quote than on install day.

What a tidy job looks like at the board

The same Energy Safe Victoria guidance lists the five defects auditors found most often in split system installations done under a Victorian government heating and cooling program. Four of the five were at the switchboard:

• Cables entering an enclosed switchboard through openings that were not a close fit, which matters for keeping a fire at the board from spreading.
• Circuit breakers not labelled to show what they supply.
• Neutral conductors not marked or arranged to match their circuit breakers.
• Outgoing neutrals not given a separate terminal each on the neutral bar.

Most of that is behind the cover, and you should not take a cover off to check it. You can check the labelling. After the install, open the switchboard door and look for a clear label on the new circuit. Then close it again.

The paperwork you should receive

The fact sheet is direct: at the completion of the installation you must be given an Energy Safe Victoria Certificate of Electrical Safety and a plumbing compliance certificate.

Energy Safe Victoria lists air conditioning as an example of non-prescribed electrical work. That means no independent inspection is required, the circuit is turned on once the work is complete, and the electrician must give you a copy of the certificate. Keep both certificates with the house papers.

You can check licences before anyone starts. The fact sheet points to ESVConnect for checking an electrician's licence status. The Victorian Building Authority now trades as the Building and Plumbing Commission, and its public search lets you check whether a plumber is registered or licensed and what type of work they are allowed to do.

What you can do before booking

None of this involves touching anything electrical.

• Choose the model first and read its installation manual, so you know whether it needs a dedicated circuit.
• Open the switchboard door, take a photo of the board, and close it again. It helps the installer see what they are working with.
• Work out roughly where the outdoor unit will sit and how far that is from the board.
• Ask each quote who is doing the electrical work and under which licence.
• Press the test button on your existing safety switch. If it does not trip, mention that to the electrician.

What to do next

If a split system is going in before summer, get the electrical side quoted alongside the unit rather than treating it as an afterthought. Make sure a licensed electrician working for a registered electrical contractor does the circuit, and do not let the job finish without both certificates in hand.