Why does AC get mouldy? Humidity and dust are the culprits
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If the AC hits you with a sour, musty mould smell, it is enough to make anyone lose it. Even though the filter has been washed, why is the inside still a breeding ground for mould? In fact, the way an air conditioner works naturally makes it easy for dirt to build up. To solve this blind spot, you need to identify the two main culprits: high humidity and dust.
Humidity: condensation creates the perfect breeding ground
When an air conditioner is cooling, it draws in warm air for heat exchange, and moisture in the air condenses into water droplets that cling to the heat sink and fan. After the unit is switched off, the inside becomes extremely humid. This dark, enclosed space full of moisture is exactly what mould likes. If the unit is not dried before shutdown, mould spores can multiply rapidly within a few days and turn into black spots.
Dust: a rich nutrient source for mould
Mold also needs food to grow, and indoor dust is the key. Even with regular filter cleaning, fine dust, skin flakes, hair and even cooking fumes can still pass through gaps and enter deep inside the unit. Once these organic particles come into contact with damp components, they stick to them and provide rich nutrients for mold. The combination of humidity and dust creates a vicious cycle that allows mold to spread quickly.
Find professional help
For stubborn mould hidden deep inside, wiping the surface yourself or using chemical sprays at random is useless and may even damage parts and cause a short circuit. To remove it completely, seeking help from a professional AC cleaning team is the safest option.
Professional technicians will dismantle components, use high-pressure water and safe cleaning agents to thoroughly wash the deep parts of the heat sink, and carry out a complete clean. After cleaning, airflow can improve, helping the AC run more smoothly and keep the environment dry.
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