Filter pads are one of the most important components inside an evaporative air conditioner.
They are responsible for absorbing water and allowing fresh air to be cooled before entering your home.
Over time, filter pads naturally wear out and become contaminated with dirt, minerals, scale and organic material. When this happens, cooling performance can suffer and operating costs can increase.
One of the most common questions we receive from Perth homeowners is:
“How often should evaporative cooling filter pads be replaced?”
The answer depends on several factors, including water quality, usage and maintenance history.
What Do Filter Pads Actually Do?
Evaporative cooling works by passing warm outside air through wet filter pads.
As air moves through the pads:
• Heat is absorbed
• Air temperature drops
• Fresh cooled air enters the home
The cleaner and more efficient the pads are, the better the system performs.
When pads become blocked or deteriorated, airflow and cooling performance are reduced.
Why Filter Pads Wear Out
Perth water contains minerals that gradually build up inside evaporative cooling systems.
Over time, filter pads accumulate:
• Scale
• Dirt
• Dust
• Algae
• Sludge
• Organic debris
This buildup restricts airflow and reduces the pad’s ability to absorb and distribute water effectively.
Eventually the pads can become so clogged that the system struggles to cool properly.
Signs Your Filter Pads Need Replacing
Common signs include:
• Reduced cooling performance
• Increased humidity inside the house
• Poor airflow
• Musty or unpleasant smells
• Visible scale buildup
• Pads that are brittle or damaged
• Water distribution problems
Many homeowners notice these symptoms gradually over several summers.
Because the decline is often slow, the reduced performance can go unnoticed until the pads are inspected.
How Long Do Filter Pads Last?
There is no exact replacement interval that suits every evaporative cooler.
Generally speaking:
• Well-maintained systems may achieve several years of service from a set of pads.
• Heavily used systems may require replacement sooner.
• Poor water quality can shorten pad lifespan.
• Lack of annual servicing often accelerates deterioration.
The best approach is to have the pads inspected during each annual service.
A technician can determine whether replacement is necessary based on the condition of the material.
Why Annual Servicing Matters
During an evaporative cooler service, technicians inspect:
• Filter pad condition
• Water distribution
• Scale buildup
• Reservoir cleanliness
• Drain operation
This allows problems to be identified before cooling performance deteriorates significantly.
Many homeowners are surprised by the amount of scale and debris that accumulates inside a system over time.
Regular maintenance helps maximise pad life while ensuring efficient operation.
Can Dirty Filter Pads Cause Humidity?
Yes.
One of the most common causes of excessive humidity inside a home is heavily contaminated filter pads.
When pads become blocked with sludge and mineral deposits, airflow through the unit is restricted.
The cooler may still introduce moisture into the home but struggle to achieve effective cooling.
This often creates the uncomfortable feeling of a humid or sticky house.
Replacing worn pads can dramatically improve comfort levels.
Do Different Brands Use Different Pads?
Yes.
Different manufacturers use different filter pad designs and fastening systems.
Common variations include:
• Side-clipping systems
• Pin-fastened systems
• Rigid media pads
• Honeycomb-style pads
It is important that the correct replacement pads are fitted for the specific model.
Using incorrect pad thicknesses or poor-quality alternatives can affect cooling performance and airflow.
Is It Worth Replacing Filter Pads?
In most cases, absolutely.
New filter pads can improve:
• Cooling efficiency
• Airflow
• Water distribution
• Indoor comfort
• Energy efficiency
They are often one of the most effective upgrades available for an ageing evaporative cooler.
Many homeowners are surprised by the improvement after replacing heavily worn pads.
Book A Filter Pad Inspection In Perth
If your evaporative cooler is not performing as well as it used to, worn filter pads could be the cause.
Air Legends services and repairs all major evaporative cooling brands throughout Perth and can inspect, clean or replace filter pads where required.
Contact Air Legends today to arrange a service and keep your evaporative cooler operating at its best.