Multiple split system (or multi-head) air conditioners comprise several wall split air conditioners powered by one outdoor unit.

Advantages of Multiple Split System Air Conditioning

• Flexibility – Individual room temperature and air flow control (as you have a split in each room).
• Running costs – Potentially lower running costs than many ducted reverse cycle air conditioners if you need to treat less than the zoned area designated with ducted reverse cycle air conditioning.
• Design  – No worrying about return air or temperature sensor location. (Which can cause performance issues with poorly designed ducted reverse cycle air conditioning).

Disadvantage of Multiple Split System Air Conditioning

• Purchase cost – it is more expensive to purchase a multi-head air conditioning system than ducted reverse cycle air conditioning.
•  Obtrusive- you have to wall mount the split system indoor unit in each room you want treated. With ducted reverse cycle air conditioning there is one indoor unit which is located in the roof space. Duct is then run from the indoor unit to outlets in each room. Also, with multi-head air conditioning, there will be more runs of pipe and electrical cable outside as it is run from one outdoor unit to many indoor units.
• Hard to provide a fixed price quote – With multi-head air conditioners you require long runs of electrical cabling and refrigeraton pipe. The rules governing how cabling and pipe is run are not simple so it is not possible to provide an accurate price for cabling and pipework at quote stage. The price can only be determined once the job is completed.

Leading brand ducted reverse cycle air conditioners (Daikin, Actron, Panasonic etc) have options which allow individual room or zone temperature control and some flexibility in air flow so the benefits of multiple split systems are not as strong as they used to be.

You have to buy a specialist multi-head outdoor unit which is relatively expensive. You cannot buy a split system and add another indoor unit to it.

Consequently, multi-heads are not common and are generally used when there is insufficient roof space or no access (penetrations) for ducting to reach the ground floor of a double storey home.

Multiple split system air conditioning is normally supplied and installed by specialist air conditioning dealers because it is more complex to design and install than a standard split system air conditioner.

Air and Water Residential, in Perth, are specialists in the supply and installation of Daikin and LG multiple split system air conditioners.