What Size Room will a 3.5kW Air Conditioner Cool?

Are you in the market for an air conditioner but not sure how much wattage your home needs? Navigating AC capacity vs room size can be confusing, and not something that you want to get wrong when investing in air conditioner installation.

Thankfully, there’s a simple equation you can use to gain an approximate understanding of the wattage you need your new air conditioner to be capable of, in order to keep your household comfortable all year round.

A general rule of thumb is to allow 0.15kW per square metre of floor space. So for example, if you’re just looking to heat/cool your bedroom which is 15sqm, then 2.25kW should be sufficient (although air conditioning units typically start at 2.6kW, so you’ll have no problem keeping the room at an ideal temperature).

However, if you’re looking to heat/cool an entire 55sqm apartment with a single AC unit, or the upper floor of a 100sqm two-storey house, then ideally you’ll need to invest in a 7-8kW air conditioning system.

How much space will a 3.5kW air conditioner be able to heat/cool?

So by this logic, a 3.5kW air conditioner should be sufficient for a room around the 20sqm-30sqm mark. If the room is any larger than this, you’ll likely be disappointed in the time it takes for the air conditioner to do its job (if it manages to heat/cool the space at all).

Here’s a quick guide to speed up your calculations:

For 10sqm-20sqm rooms, get a portable or split-system air conditioner between 2.6kW and 2.8kW.

For 20sqm-30sqm rooms, get a 3.5kW split-system air conditioner.

For 30sqm-40sqm rooms, get a split-system air conditioner between 5kW and 6kW.

For 40sqm-50sqm rooms, get a split-system air conditioner between 6kW and 8kW.

For rooms bigger than 50sqm, get a split-system air conditioner capable of 8kW or higher.

Other factors for cooling/heating your room with a 3.5kW air conditioner

Measuring the floor space (i.e. multiply the room’s length by its width to determine the room’s square metreage) is a good rule of thumb for calculating the required air conditioner wattage. However, there are exceptions.

For instance, if the room has particularly high ceilings, you might need more wattage than what the SQM x 0.15kW calculation will give you. Another variable is your home’s insulation – if your property has good insulation, a lower wattage air conditioner might be capable of heating/cooling your home because the insulation is trapping the air inside more efficiently.

Which air conditioner best suits your needs?

At QuickAir, we supply quality-made air conditioners of every output capacity, from industry-leading brands. Whether you’re interested in a split-system AC unit, evaporative cooling system, ducted reverse cycle aircon or other variety, don’t hesitate to get in touchwith QuickAir for expert advice and recommendations.

We can take care of all your air conditioner installation, repairs and servicing needs.