Multi-Split vs Single-Split Air Conditioning

The difference

A single-split is one indoor unit paired with one outdoor unit. A multi-split connects two to five indoor units to a single larger outdoor unit, with pipework branching to each room.

Both use the same underlying technology; the difference is how the outdoor capacity is shared.

The case for multi-split

One outdoor unit instead of four is a big win where wall space, garden space or aesthetics are constrained — terraced houses, small courtyards, flats with a single permitted plant location.

It also reduces the number of external penetrations and can look considerably tidier.

The case for separate single-splits

Separate systems are independent. If one develops a fault, the other rooms carry on working. They also allow different room types to be matched with better-suited equipment, and they often run more efficiently at part load because each condenser is sized for its own room.

Where there is space for two discreet condensers, this is frequently the better engineering answer.

• Redundancy — a fault does not take out the whole house
• Better part-load efficiency in many scenarios
• Simpler faultfinding and cheaper repairs
• Often lower installed cost for two rooms

What it does to cost

For two rooms, two single-splits are usually similar or cheaper than a multi-split. From three rooms upward, multi-split often becomes the more economic and better-looking option.

The honest answer depends on your building. We price both where both are viable so you can choose with the numbers in front of you.