How to Choose a Replacement Filter for a Residential Evaporative Cooler in Brisbane

If your evaporative cooler is no longer cooling evenly, is letting more dust through, or the pad looks worn or damaged, the issue may be as simple as needing the right replacement filter. For Brisbane homeowners, the safest way to choose one is to match the cooler’s make, pad style and cabinet dimensions before ordering, rather than guessing from a photo alone.

This guide explains the details that matter most when you are replacing a pad or filter in a rooftop or window-mounted evaporative cooler, and how to measure the unit so you get a proper fit the first time.

Start with the cooler make and model

The first step is to identify the cooler itself. The make and model usually narrow down the style of filter or pad you need, especially for older rooftop units or window-mounted coolers where parts are not interchangeable across brands.

Look for the model plate or label on:

• •The exterior cabinet
• •The access panel
• •The motor or control area
• •The original paperwork, if you still have it

Write down the brand name, model number and any serial details you can find. If the label is faded, take a clear photo and enlarge it on your phone. Even partial information can help when you are comparing replacement options.

If you are unsure, contact us with the details you do have. At Total Air Filtration, a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, we can help identify a suitable replacement from the information on hand.

Check what type of pad or filter the cooler uses

Evaporative coolers do not all use the same filter or pad style. Some use rigid pads, some use framed inserts, and others use panel-style media that sits in a specific track or holder.

Common things to check include:

• •Whether the pad is rigid or flexible
• •Whether it sits inside a frame
• •Whether the media is honeycomb-style, fibrous, or another style
• •Whether the unit uses one-piece pads or multiple smaller sections
• •Whether the replacement needs holes, cut-outs or notches for clips, screws or water distribution parts

If you have the old pad, compare the construction rather than only the outer size. A pad can be close in dimensions but still fail to fit if the edge profile, frame depth or fixing method is different.

Some filters are designed to be washable - check the product instructions if that is important for your application. If the original pad was built to be replaced rather than cleaned, do not assume a washable product will suit the cooler just because it looks similar.

Measure the cabinet carefully before ordering

Once you know the make and pad style, measure the space the filter must fit into. This matters for both rooftop units and window-mounted coolers, because even small differences in cabinet dimensions can affect fit and airflow.

Use a tape measure and check:

• •The overall height and width of the opening
• •The depth available for the pad or filter
• •The thickness of the existing pad
• •Any frame or channel depth the pad sits in
• •The size and position of cut-outs, lips, tabs or locating edges

For the most accurate result, measure the cabinet opening and the old pad separately. Old pads can compress, swell or warp over time, so relying on the old pad alone can lead to the wrong size.

If you want a guide on measuring, our how to measure an air filter page is a useful place to start. The same careful approach applies to evaporative cooler pads: measure the space, then confirm how the pad is held in place.

What to note when measuring

When you take measurements, record them in millimetres and note anything unusual about the opening.

Helpful details include:

• •Fixed frame thickness
• •Direction of airflow through the pad
• •Whether the pad slides in from the side, top or front
• •Any obstructions inside the cabinet
• •Whether the panel must seal tightly or allow a small locating gap

If the cooler is mounted on a roof, it is worth checking that the access is safe before removing the old filter. If a roof-mounted unit is difficult to reach, it may be better to arrange servicing rather than forcing the panel out and damaging the cabinet.

Match the pad style to the cooling system

A replacement filter needs to suit the way the cooler was built, not just its outer measurements. The pad style affects how water is spread, how air moves through the unit and how securely the pad sits in the cabinet.

Look for these matching features:

• •Same overall pad shape as the original
• •Same thickness or the thickness specified by the manufacturer
• •Similar frame or edge profile
• •Same fixing points or locating tabs
• •Correct orientation for water entry and airflow

For some older systems, the original part may no longer be available. In that case, a custom-made replacement can be the better option, especially if the cabinet dimensions are unusual or the original pad has been modified over time.

If you need a made-to-size solution, see our custom air filters page. We can supply or make filters to suit many residential applications, including evaporative cooler setups that need a specific fit.

When the old filter is missing or damaged

Sometimes the old pad has been thrown out, collapsed or broken beyond use. That does not mean you have to guess. You can still identify the right replacement by combining a few details.

Try to gather:

• •The cooler make and model
• •Photos of the cabinet opening
• •The exact cabinet opening measurements
• •Any remaining clips, rails or support frames
• •A description of how the pad was installed

If you are comparing options, send photos from several angles. A straight-on shot, a side view and a close-up of the pad channel can make a big difference. For unusual units, a replacement may need to be made to match the existing cabinet rather than relying on a standard catalogue size.

If the system also needs broader servicing, our filter servicing page explains the kind of support we provide for filter-related maintenance.

A few practical checks before you buy

Before ordering, run through a final check so the replacement arrives ready to install.

Make sure you have confirmed:

• •The cooler’s make and model
• •The pad or filter style
• •The measured cabinet opening
• •The pad thickness and any cut-outs
• •Whether the replacement should be standard or custom made

If the cooler is part of a larger ventilation setup, confirm the site requirements with the mechanical services engineer or building owner, especially where standards or ventilation design requirements are relevant. For some installations, AS 1668.2:2024 may be part of the discussion, but the exact site requirements still need to be checked for the specific system.

It is also worth inspecting the rest of the unit while the panel is open. Debris in the cabinet, blocked water distribution parts or damaged seals can affect performance even when the replacement pad is correct.

Get the right replacement without guessing

Choosing the right evaporative cooler filter comes down to three things: the make and model, the pad style, and the cabinet dimensions. If you have those details, you can avoid trial and error and order with confidence.

Total Air Filtration can help Brisbane homeowners identify, supply or make the right replacement for rooftop or window-mounted evaporative coolers. Call 07 3800 3448 or request a quote.