How to Choose the Right Diffuser for Your Ducted Air Conditioning System

Diffusers are one of the few visible parts of a ducted air conditioning system. They’re mounted in the ceiling, and their job is to evenly distribute the air throughout the space. When installing ducted air conditioning systems, several styles of diffusers are available to choose from.

And it’s not just for looks, either. Your system’s diffuser controls the direction and volume of your AC’s airflow, so it plays a major role in your system’s performance and reliability.

Not sure what diffuser to pick? Don’t worry – we’re here to help. Here’s a quick guide on how to choose the right diffuser for your ducted AC system:

Know the Main Types of Diffusers

Familiarising yourself with the different types of diffusers will help point you in the right direction. Some of the main types of diffusers for ducted AC systems include:

  • Round Diffuser – Round diffusers are among the most popular choices for homeowners, thanks mainly to its simple design that blends in easily with different rooms. But because of its small size, you may need multiple diffusers if being installed in large living spaces.
  • Square Diffusers – These diffusers are commonly used in large offices and spaces with unconventional layouts. They often come in either silhouette or multi-directional configurations, both of which can diffuse air in multiple directions simultaneously. Multi-directional versions are particularly good options if even air distribution is a priority, although the large and visible design can make it an eyesore for some people.
  • Side Wall Diffuser – You’ll often see these diffusers high up on the walls near the ceiling, and they’re commonly used for ducted AC systems that are set up behind walls. Their flat and plain designs make them easy to pair with different styles of rooms, while their wide openings allow you to ramp up airflow in your room quickly.
  • Linear Slot – This long and narrow diffuser is perfect on high walls and ceilings, providing a clean and simple design that won’t get in the way of your room’s design. This diffuser is, however, limited in function since it’s only used for bulkhead systems and only controls airflow in one direction.


Consider Key Factors

Choosing a diffuser for your ducted AC system is more than just about picking what looks right in your room. You’ll also need to consider the following factors:

  • Room size – The size of your room can determine the right type of diffuser for your system. Square diffusers and side wall diffusers, for example, are ideal for large rooms, while smaller diffusers like round diffusers are great for more compact spaces. Your room size can also help you determine the number of diffusers you’ll need to install to provide proper air conditioning.
  • Room configuration – Is your living space a typical square room or does it have a more unconventional layout? Consider the configuration of your room to determine which directions you need the air to flow in and what diffusers can make that happen.
  • Room style – Some diffusers are more visible and noticeable than others, making them more difficult to incorporate in an existing room design. If you want to maintain your room’s style and aesthetics, then diffusers with minimal visual impact will be your best option.
  • Type of AC – Some diffusers work best with particular kinds of ducted AC systems (e.g. linear slot diffusers for ducted ACs behind walls), so make sure your preferred diffuser is compatible with your system.
  • Airflow needs – Do you want to target airflow in certain parts of your room? Or do you simply need general air-conditioning in your living space? Some diffusers provide targeting features that make it easy to control the volume and direction of airflow in your room.

Consult Your AC Supplier

Once you’ve considered these factors and picked your preferred diffuser, we recommend consulting with your AC supplier to make sure it’s the right choice for your living space.

A qualified professional can provide information and advice that will inform your decision and confirm whether you’re making the right choice. They can also spot potential issues with your living space and provide recommendations to work around them.

A second opinion from an expert will always be valuable and helpful.

Need Help Choosing a Diffuser?

If you’re not sure what diffuser will work best for your room, don’t hesitate to contact us for assistance. We’ll be glad to help you decide so you end up with the right choice for your system.


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