Choosing the Right Air Conditioner for an Open-Plan Living and Dining Area
Open-plan living spaces are the dominant layout in modern Australian homes — a combined kitchen, dining and living area that flows together without internal walls. Choosing the right air conditioner for this space requires more thought than a single bedroom or study. This guide explains how to get it right.
Why Open-Plan Spaces Are Different
An open-plan area has three key characteristics that affect air conditioning selection:
- Large volume — combining kitchen, dining and living means you're often cooling 50–100 square metres or more in one space
- Heat sources — the kitchen generates significant heat from cooking, and multiple people dining add body heat. This increases the cooling load
- Ceiling height — modern homes often have higher ceilings in living areas (2.7m or higher), which means more air volume to cool
Calculating the Right Capacity (kW)
The standard starting point for sizing an air conditioner is approximately 100–125W of cooling capacity per square metre for average Australian conditions. For an open-plan space in Western Sydney (which has more extreme heat than coastal areas), use the higher end of this range or add a buffer.
Guidance by area:
- Up to 50m²: 5–6kW
- 50–75m²: 6–8kW
- 75–100m²: 8–9kW
- 100m²+: Consider multi-split or ducted
Adjust upward if the space has high ceilings, significant western sun exposure, poor insulation, or is in a very hot location like Penrith, Blacktown or Campbelltown.
Single Split System vs Multi-Split vs Ducted
Single Large Split System
A single powerful split system (7–9kW) installed in an optimal position is often sufficient for a large open-plan space. This is the most cost-effective solution and easiest to install. The limitation is that airflow may be uneven in very long or L-shaped spaces.
Multi-Split System
A multi-split uses one outdoor unit connected to two or more indoor heads. This is ideal for open-plan areas that extend into an L-shape or where a single indoor unit can't reach all areas effectively. Each indoor head can be individually controlled. The installation cost is higher than a single split but lower than ducted.
Ducted Air Conditioning
Ducted is the premium solution — the system runs through the ceiling with vents throughout the home. It's invisible except for the vents, cools evenly across all rooms, and is the most comfortable solution. It's also the most expensive to install ($6,000–$15,000+). Best suited to new builds or major renovations where the ceiling can be accessed.
Placement of the Indoor Unit
For a large open-plan space, the indoor unit should ideally be positioned on an internal wall that allows airflow to reach the furthest parts of the space. For an L-shaped living/dining/kitchen, the unit on the long wall of the main living area, positioned to blow across the full length of the space, is usually the best placement. Avoid positioning opposite a window where direct sun can interfere with the sensor.
Best Brands for Large Split Systems
For 7–9kW units capable of cooling large open-plan spaces, Daikin and Mitsubishi Electric are the most recommended brands among professional installers. LG and Samsung also offer strong options at more competitive prices.
Find the Right Unit at Oceania Appliances
We stock a range of large split systems (6kW, 7.1kW, 8kW, 9.2kW) from Daikin, Mitsubishi Electric, Samsung and LG as ex-display and graded units at significant discounts. Free delivery across Sydney. Contact us to find the right unit for your open-plan space.