Living in the Klang Valley means your aircond is essentially a life support system.
You know the feeling when the humidity hits 80% and the cooling just isn’t cutting it?
We see this scenario daily at PJ Kool Aircond Service.
Your unit rarely stops working overnight without giving you a few hints first.
The problem is that most homeowners in Petaling Jaya wait until the unit stops cooling entirely or floods the parquet flooring before calling for help.
By that point, a simple maintenance job has often escalated into a costly repair.
I have spent over 20 years servicing units across KL and Selangor.
My team has identified five specific red flags that indicate your unit is overdue for a chemical wash.
If you spot even one of these, you need to act.
And if you notice sign number three, take action immediately since it directly impacts your family’s respiratory health.
Let’s look at the clear warning signs and the specific fix for each one.
Sign 1: Weak or Warm Airflow
You set your remote to 16 degrees and turn the fan to maximum.
You stand directly under the unit expecting a blast of cold air.
Instead, the air feels lukewarm at best, and the breeze is barely strong enough to move a piece of paper.
Why This Happens
The evaporator coil is the engine room of your cooling system.
When layers of dust, kitchen grease, and grime build up on the coil fins, they create a thick blanket of insulation.
This prevents the coil from absorbing heat from your room efficiently.
The air passes over the coil but never actually gets cooled.
There is also a mechanical issue at play here.
Dirt buildup on the blower fan (the cylindrical roller inside the unit) dramatically reduces its ability to push air outward.
Heavy dust makes the fan blades unbalanced.
They spin less efficiently and struggle to throw air across the room.
Pro Tip: If you can see visible dust bunnies sticking to the vent louvres, the internal blockage is likely 10 times worse than what you see on the surface.
How a Chemical Wash Fixes It
A standard water cleaning often cannot remove the sticky “bio-film” that adheres to the coils.
A chemical wash uses an alkaline-based solution to dissolve this insulating layer on the coil fins.
This restores the full heat exchange capacity immediately.
Cleaning the blower fan restores airflow to its original volume.
Most customers are surprised by the sheer force of the wind coming out of the unit after we finish the job.
Sign 2: Water Leaking from the Indoor Unit
Water dripping from your aircond onto the wall is one of the most frustrating issues homeowners face.
It is messy, it damages paint, and it ruins expensive flooring.
We find this is the number one reason people finally pick up the phone.
Why This Happens
Your aircond naturally produces water (condensation) as it cools the warm air in your room.
This water collects in a drain tray and flows out through a drainage pipe.
In Malaysia’s tropical climate, a substance we call “jelly” or bio-slime grows rapidly in these wet areas.
When the drainage pipe or drain tray becomes clogged with this slime, dirt, or algae, the water has nowhere to go.
It backs up and overflows from the unit.
Here is what that water can damage if left unchecked:
- Plaster Ceilings: Water stains turn yellow and eventually cause the plaster board to rot.
- Parquet Flooring: Constant dripping causes wood to warp and turn black.
- Electronics: Water often drips directly onto TVs or computers placed below the unit.
How a Chemical Wash Fixes It
The chemical wash process is the only way to fully clear this “jelly.”
We perform a high-pressure flush of the drainage system to force out the blockage.
The drain tray is then chemically sanitised to kill the biofilm that causes recurring clogs.
This is the most immediate fix—the leaking stops the moment the service is complete.
Sign 3: Musty or Mouldy Smell (Do Not Ignore This One)
This is the sign you must prioritize above all others.
If your aircond produces a smell like damp socks or mildew when it first starts up, you have a biological contamination problem.
Why This Happens
Malaysia’s humidity creates the perfect breeding ground for mould like Aspergillus and Cladosporium.
These fungi colonise the damp evaporator coil, the drain tray, and even the blower fan.
Every time you turn your aircond on, the fan blows air directly over these mould colonies.
This pushes spores right into your bedroom or living room.
Why It Is Dangerous
Breathing in mould spores for 8 hours a night is a serious health risk.
We often see customers who have been treating chronic allergies without realising the source is on their wall.
Exposure can lead to:
- Allergic reactions: Sneezing, runny nose, and itchy eyes.
- Asthma triggers: Dangerous for children and elderly family members.
- Respiratory infections: Prolonged exposure can lead to bronchitis or persistent coughs.
- Fatigue: Poor indoor air quality often leads to poor sleep quality.
How a Chemical Wash Fixes It
You cannot wipe this away with a cloth.
The chemical solution used in a professional wash is specifically formulated to break down biological contaminants.
The high-pressure flush removes the dead organisms along with the grime they were feeding on.
After a chemical wash, the smell disappears completely because the source has been eliminated.
Sign 4: Higher Electricity Bills
Have you noticed your TNB bill creeping up despite using your appliances the same amount?
Your aircond is likely the culprit.
Why This Happens
A dirty unit is an inefficient unit.
When the coil is choked with dust, the compressor has to work overtime to cool the room.
If you have an inverter unit, it will run at maximum speed for longer rather than ramping down to a power-saving mode.
Research indicates that a dirty aircond can use 15% to 30% more electricity than a clean one.
Let’s look at the potential cost impact for a standard household in PJ:
| Item | Clean Unit Cost (Est.) | Dirty Unit Cost (Est.) | Monthly Loss |
|---|---|---|---|
| Daily Usage | 10 Hours | 10 Hours | - |
| Power Draw | 1.0 kWh | 1.3 kWh (+30%) | - |
| Monthly Cost | RM150 | RM195 | RM45 |
Estimates based on average tariff rates for a 1.5HP unit running daily.
For a household running three units, you could be wasting over RM130 every month.
How a Chemical Wash Fixes It
Cleaning the coil restores the unit’s efficiency rating.
The compressor runs shorter, less strenuous cycles to reach your desired temperature.
Many of our PJ Kool customers report a noticeable drop in their TNB bill within the first month after a chemical wash.
Sign 5: Unusual Noises
A healthy aircond should be “whisper quiet,” usually producing under 25 decibels of sound.
If you start hearing rattling, buzzing, or gurgling, the unit is struggling.
Why This Happens
Different sounds indicate different problems caused by dirt:
- Rattling: This often means the blower fan is so heavy with dust that it is spinning off-balance.
- Buzzing: This can be caused by ice forming on a dirty coil and vibrating against the casing.
- Gurgling: This suggests the drainage pipe is partially blocked, and water is struggling to flow down the gravity pipe.
- Clicking: While sometimes electrical, this can also be debris hitting the fan blades.
How a Chemical Wash Fixes It
A chemical wash resolves the mechanical causes of these noises.
Cleaning the blower fan restores its balance, eliminating the rattle.
Clearing the drainage stops the gurgling immediately.
Removing the coil buildup prevents the ice formation that causes buzzing.
What to Do If You Notice These Signs
If you recognise any of these symptoms, you need to choose the right solution.
Here is my advice on how to proceed:
- Do not wait: The longer you run a dirty unit, the more stress you put on the expensive compressor.
- Choose the right service: A “general service” (vacuum and water only) will not remove the biological buildup causing these issues.
- Verify the technician: Improper use of chemicals can corrode your coils; ensure you hire experienced pros.
Service Comparison: What Do You Need?
| Feature | General Service | Chemical Wash | Overhaul |
|---|---|---|---|
| Best For | Routine upkeep | Bad smells / Weak air | Total breakdown |
| Chemicals Used | No | Yes (Coil Safe) | Yes (Strong) |
| Removes Mould | Partially | Yes (99%) | Yes (100%) |
| Price Range | Low | Medium | High |
At PJ Kool Aircond Service, our chemical wash starts from RM160 for wall-mounted units.
We include a free gas top-up to ensure your cooling is perfect.
Our senior technicians average 15 years of experience and will always give you an honest diagnosis.
Contact us today to book your chemical wash and restore your aircond to peak performance.
Mr. Heng
Founder & Lead HVAC Technician
Founder of PJ Kool Aircond Service with 20+ years of HVAC expertise in Petaling Jaya.
