🦠 What Causes Mould Growth in the Aircon Unit?

Mould growth inside the aircon unit is a very common issue in Singapore homes, especially due to high humidity and frequent aircon usage.

Many homeowners only notice the problem when a musty smell, reduced cooling, or allergy symptoms appear. In reality, mould starts forming quietly when moisture, dirt, and poor airflow combine inside the unit.

Here are the most common reasons mould develops in aircon systems.

1. Trapped Moisture Inside the Unit

Aircons remove moisture from the air during cooling. If the internal components do not dry properly, moisture remains trapped inside.

Why this happens:

• Aircon switched off immediately after use

• Poor airflow inside the unit

• High humidity environment

This damp condition creates the perfect environment for mould growth.

2. Dirty Evaporator Coil and Filters

Dust and dirt accumulate on filters and coils over time. When moisture passes over dirty surfaces, mould begins to form and spread.

Common signs:

• Musty or sour smell

• Dusty air

• Reduced cooling efficiency

• 
  

Dirty components are one of the most common mould triggers.

3. Clogged Drain Pipe or Drain Pan

When water cannot drain out properly, it collects inside the unit. Standing water accelerates mould and bacteria growth.

Possible causes:

• Algae buildup in the drain pipe

• Dust blocking the drain pan

• Poor maintenance

This often leads to both mould and water leakage issues.

4. Infrequent or Irregular Servicing

Without regular servicing, internal components remain dirty and damp for long periods.

What happens over time:

• Mould spreads deeper into the unit

• Odours worsen

• Air quality deteriorates

Servicing helps remove mould before it becomes severe.

5. Poor Airflow and Weak Fan Performance

Weak airflow prevents moisture from drying properly. This allows damp areas inside the unit to persist.

Possible reasons:

• Worn blower fan

• Blocked filters

• Dirty coils

• 
  

Poor airflow increases both mould risk and energy usage.

How Sky Blue Aircon Helps Homeowners

At Sky Blue Aircon Engineering Pte Ltd, we address mould issues by identifying the root cause, not just masking the smell.

Our services include:

• Internal coil and filter cleaning

• Chemical wash for mould and bacteria removal

• Drain pipe flushing and inspection

• Airflow and fan performance checks

• Usage advice to prevent recurrence

This helps restore clean airflow and healthier indoor air.

💡 The Bottom Line

If you smell something burning from your aircon, it is a warning sign that should not be ignored. Fixing the issue early prevents electrical damage, protects your home, and keeps your aircon safe to use.

📲 Message us on WhatsApp at 9248 7291 or call 6556 4042.

Sky Blue Aircon Engineering Pte Ltd keeping Singapore homes cool, clean, and