Rainy days in Malaysia often trick us. The sun disappears, temperatures drop slightly, and yet—somehow—your home feels damp, sticky, and uncomfortable. You might even feel sleepier, lazier, or irritated for no obvious reason. The truth is, rainy-day discomfort has very little to do with temperature and everything to do with humidity.
When it rains, moisture levels in the air rise sharply. Malaysian homes, especially terrace houses and apartments, are designed to keep rain out—not moisture. Windows stay closed, air circulation drops, and humidity gets trapped indoors. Your walls, furniture, curtains, and even mattresses slowly absorb moisture throughout the day.
This creates an indoor environment that feels heavy and stale. Sweat doesn’t evaporate properly, clothes feel damp, and rooms smell musty. Even at 27–28°C, your body struggles to cool itself. That’s why rainy days often feel more uncomfortable than sunny ones. Without the right aircond settings, you’re basically living inside a sponge.
This is one of the most expensive myths in Malaysian households. Many people turn off their aircond completely during rainy days, thinking they’re saving electricity. In reality, this often leads to higher costs and more problems later.
When the aircond is off, humidity builds up rapidly. Moisture settles inside the indoor unit, drainage pipes, and ducts. Mold and bacteria start growing quietly. The next time you switch the aircond on, you notice a bad smell, weaker airflow, or even water leaking.
From a comfort perspective, turning off the aircond completely makes indoor air heavier and harder to breathe. From a health perspective, damp environments worsen allergies, asthma, sinus problems, and skin irritation.
Using your aircond correctly on rainy days doesn’t waste money—it prevents damage, improves comfort, and protects your health.
Many people think airconds only cool air. In reality, air conditioners have two jobs:
Remove heat
Remove moisture
On hot, sunny days, most of the work goes into removing heat. On rainy days, the heat load drops—but moisture removal increases significantly. Your aircond spends more time dehumidifying than cooling.
This is why rooms sometimes feel cold but still uncomfortable. The system is busy pulling moisture out of the air, which takes time and energy. If your settings aren’t optimized, the aircond may overcool the room without effectively reducing humidity.
Understanding this shift helps you choose the right mode and temperature—so the aircond works with the weather, not against it.
Humidity affects how your body feels temperature. High humidity prevents sweat from evaporating, trapping heat against your skin. That’s why you feel sticky even when the air feels cool.
But discomfort is only part of the problem. Excess humidity causes:
Mold growth on walls and ceilings
Musty smells from airconds
Dust mite population increase
Damp mattresses and sofas
Damage to electronics and wooden furniture
Long-term exposure to high humidity impacts sleep quality and respiratory health. Controlling humidity isn’t optional in Malaysia—it’s essential. Your aircond is one of the most effective tools for doing this, if used properly.
For rainy days in Malaysia, the most efficient and comfortable temperature range is 25°C to 27°C.
Anything lower than that usually leads to:
Overcooling
Higher electricity bills
Cold-related discomfort
Poor sleep quality
Since outdoor temperatures are already lower, your aircond doesn’t need to work as hard to cool the room. At higher settings, it can focus on moisture removal while maintaining a stable, breathable indoor environment.
Comfort isn’t about freezing the room—it’s about feeling dry, fresh, and relaxed.
Cool Mode
Removes heat and moisture
Best for warmer rainy days
Uses more electricity
Dry Mode
Focuses on dehumidifying
Uses less power
Prevents overcooling
On rainy days where the room feels sticky but not hot, dry mode is the best choice. It reduces humidity efficiently without dropping the temperature too much.
A smart strategy is to start with cool mode to stabilize the room, then switch to dry mode once it feels comfortable. This approach saves electricity and keeps humidity under control.
Fan mode only circulates indoor air. It does not remove moisture. On low-humidity rainy days, fan mode may feel okay. But during prolonged rain, it often makes rooms feel worse by spreading damp air around.
Fan mode works best when paired with aircond usage—not as a replacement. Use it after dehumidifying the room to maintain comfort without extra cooling.
Daytime Rain
Buildings store heat from previous sunny days. Cool or dry mode at 25–26°C works best.
Nighttime Rain
Outdoor temperatures drop further. Overcooling becomes a risk. Dry mode or cool mode at 26–27°C improves sleep without chills.
Adjusting settings based on time of day prevents discomfort and unnecessary energy use.
Many homeowners are surprised when their electricity bill stays high during rainy months. The reason? Long runtime due to humidity control and inefficient settings.
Using very low temperatures, ignoring dry mode, and poor maintenance force the aircond to work harder than necessary. Optimized settings can reduce rainy-season electricity costs significantly.
Rainy weather exposes different aircond issues, including:
Water leakage from clogged drain pipes
Musty or sour smells from mold
Sensor errors due to moisture
Rust and corrosion in neglected units
Ignoring these problems early leads to expensive repairs later.
Clean filters every 3–4 weeks
Flush drainage pipes regularly
Keep outdoor units dry and elevated
Schedule preventive servicing
Small maintenance habits prevent big rainy-season headaches.
Close curtains to reduce moisture entry
Use aircond during peak humidity hours
Combine aircond with ceiling fans
Turn off units once humidity drops
Comfort comes from consistency, not extreme cooling.
Inverter airconds adjust cooling gradually, making them excellent for humidity control. They maintain stable comfort with lower energy use.
Non-inverter units cycle on and off, causing temperature swings and higher power consumption. In Malaysia’s rainy climate, inverter systems offer better long-term value.
Rahima Aircond Services understands Malaysia’s climate challenges—from heatwaves to heavy rain. Rainy-season servicing focuses on drainage, humidity control, mold prevention, and efficiency optimization.
Whether it’s fixing leaks, improving air quality, or advising on the right settings, Rahima Aircond Services helps homes stay comfortable all year round.
Learn more at https://rahimaaircondservices.com
Rainy days aren’t the enemy—wrong aircond settings are. With the right temperature, mode, and habits, you can stay comfortable, protect your health, and reduce electricity bills at the same time.
In Malaysia, comfort isn’t about stronger cooling. It’s about smarter control.
1. Should I completely turn off my aircond during rain?
No. Proper usage helps control humidity and prevents mold.
2. Is dry mode cheaper than cool mode?
Yes. Dry mode uses less electricity and prevents overcooling.
3. What temperature is best for sleeping on rainy nights?
Between 26°C and 27°C.
4. Why does my aircond smell bad during rainy season?
Moisture buildup and mold inside the unit are common causes.
5. Who can help with rainy-season aircond issues?
Rahima Aircond Services at rahimaaircondservices.com.
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