Toowoomba’s unique climate means you need a reliable air conditioner to stay comfortable all year round. With summers averaging 28°C and winter nights getting quite chilly, having the right system is a must for homes across the region. Getting the size of your aircon right is crucial for saving money on your power bill and keeping your home comfortable.
This guide is for everyone living in Toowoomba, whether you’re in a classic Queenslander in East Toowoomba, a modern family home in Rangeville, or a new build in Kearneys Spring. Choosing the right size air conditioner for your home is the most important decision you’ll make. Get it right, and you’ll have a comfortable, energy-efficient home. Get it wrong, and you’ll be throwing money away on a system that struggles to keep you cool.
Let’s begin.
The Benefits of Knowing the Right Aircon Size
Choosing the correct unit for your Toowoomba property offers a lot more than just comfort. You’ll get:
- Maximum Efficiency: A properly sized unit runs as it should, using less electricity to cool the room.
- Lower Running Costs: Using less electricity means a smaller power bill. It’s that simple.
- Better Air Quality: An appropriately sized aircon unit can effectively dehumidify the air, reducing mould and mildew growth.
- Longer Lifespan: A unit that isn’t constantly overworked will last much longer, saving you money on future replacements.
Factors and Measurement for the Right Aircon Size
So, how do you figure out the right size? The key is to understand a few simple factors.
How to calculate aircon size for a room
A simple rule of thumb is to use the floor area. A good starting point is around 125 to 150 watts of cooling power per square metre. So, if your room is 20 square metres, you’d need a unit with around a 2.5kW to 3.0kW capacity.
What is BTU for aircon sizing?
In Australia, we use kilowatts (kW) as the standard measurement for an air conditioner’s cooling capacity. However, you might still see some units listed in BTUs (British Thermal Units). Just remember that 1 kW is equal to around 3,414 BTUs.
Does room height affect aircon size?
Yes, it definitely does. Aircons cool the volume of a room, not just the floor area. A room with a high or vaulted ceiling has a lot more air for the unit to cool, so you’ll need a bigger size to be effective.
Do windows and insulation affect aircon size?
Absolutely. Rooms with large windows, especially those facing the sun, gain more heat and will need a larger aircon. Good insulation in your walls and ceiling will help keep the cool air in, meaning you can often use a slightly smaller unit.
Consequences and Common Mistakes
It’s tempting to think a bigger unit is always better, but that’s a common mistake that can cost you.
What happens if my aircon is too big for the room?
A unit that’s too big will cool the room down too quickly and then switch off. This is called “short cycling.” It wastes energy, doesn’t properly remove humidity (leaving the room feeling clammy), and puts a lot of stress on the system, which can cause it to wear out faster.
What happens if my aircon is too small?
A unit that’s too small will have to run non-stop to try and reach the desired temperature. It will never truly cool the room, leading to high power bills, a lack of comfort, and a much shorter life for the unit.
Is it better to get a bigger aircon size?
No, it’s not. Getting the right size is always best. A system that’s too big is a complete waste of money.
How Your Choice of System Affects the Size
The type of aircon you choose also plays a role in sizing.
What size ducted aircon for a 4-bedroom house?
A ducted system cools the whole home, so its capacity needs to be much larger than a single split system. For a standard 4-bedroom house, you would likely need a unit in the 12kW to 18kW range, depending on the home’s layout, insulation, and the number of zones you want.
How to choose a split system aircon size?
Split systems are great for cooling one or two rooms. You’ll need to calculate the size for each individual room and install a separate unit for each.
Aircon sizing for multiple rooms
For multiple rooms, you can either install several individual split systems or consider a multi-split system, which uses one outdoor unit to power several indoor units. This allows you to cool different rooms with different-sized units, all connected to the one system.
Cost and Energy
Your aircon size is directly linked to how much you’ll spend.
How does aircon size affect running costs?
A correctly sized unit is much more energy-efficient, which means lower power bills. A unit that’s too big or too small will constantly run inefficiently, costing you more money in the long run.
Is a bigger aircon more expensive to run?
Yes, and no. While a larger unit uses more power at full capacity, a correctly sized unit that runs efficiently will often be cheaper to run than a smaller one that’s constantly overworked.
Aircon efficiency ratings and unit size
Always look for the Energy Star rating on the sticker. More stars mean the unit is more efficient, which translates to big savings over time.
Getting the right air conditioner is a job for a professional. Don’t risk choosing the wrong size. Let a professional aircon installer in Toowoomba help you find the perfect system for your rooms. Call Garden City Air HVAC for a quick, reliable, and honest aircon installation cost today.
Still thinking of an AC upgrade. Read the importance it can deliver to your home.