13 Jan Aircon Not Cold? 7 Troubleshooting Steps Before Calling a Technician

In 2026, Singapore’s climate has hit new extremes, with mean temperatures rising by nearly 0.24°C per decade, making a functional cooling system more of a survival tool than a luxury (NCCS, 2026). There is nothing more frustrating than coming home from the humid glare of Orchard Road only to find your indoor unit blowing lukewarm air.

Before you pick up the phone to book an emergency aircon repair, it is worth investigating if the issue is a simple fix you can handle yourself. Often, the “not cold” sensation is a symptom of neglected aircon maintenance rather than a catastrophic mechanical failure. By following a systematic approach, you can identify if your aircon in singapore setup needs a professional touch or just a bit of DIY care.

1. Verify Your Remote Settings (The “Ghost” in the Machine)

It sounds overly simple, but a significant percentage of service calls for aircon in singapore units are resolved by simply toggling a remote button. In 2026, many smart aircon systems feature multiple modes like “Dry,” “Fan,” and “Eco.”

If someone accidentally switched your unit to “Fan” mode, the compressor will not kick in, and you will only feel room-temperature air circulating. Ensure your remote is set to “Cool” (usually represented by a snowflake icon) and that the temperature is set at least 2°C to 3°C lower than the current room temperature.

Comparison of Aircon Modes and Their Impact

Mode	How it Works	Is it “Cold”?
Cool	Engages the compressor to lower the temperature.	Yes
Dry	Focuses on dehumidifying (good for 80%+ humidity).	Mildly
Fan	Only the indoor blower runs; the compressor is off.	No
Heat	Reverses the cycle (rarely used in Singapore).	Hot

If your settings are correct but the air remains warm, the system might be struggling with deeper issues. We can help by conducting a comprehensive system diagnostic to ensure your controller and the indoor PC board are communicating effectively. Contact us today!

2. Check for Clogged Air Filters

Dust and pet dander are the silent enemies of aircon maintenance in Singapore. When filters are coated in a thick layer of grime, airflow is restricted. This prevents the evaporator coils from effectively absorbing heat, leading to a “not cold” sensation and potentially causing the unit to freeze up.

According to recent data, a dirty filter can increase your energy consumption by up to 15% because the motor has to work significantly harder to pull air through the obstruction (SP Group, 2026). We recommend washing your filters every two weeks if you use your unit daily.

If cleaning the filters doesn’t restore the chill, there may be internal dust buildup that a simple rinse can’t reach. Jia Xing can help by providing a deep-cleansing aircon servicing that reaches the internal blowers and fins where stubborn dust hides.

3. Inspect the Outdoor Condenser Unit

The “outdoor” part of your aircon in Singapore‘s system is responsible for dissipating the heat collected from inside your home. In HDB estates or tight condo balconies, these units are often cramped or blocked by laundry, plants, or storage boxes.

If the condenser cannot “breathe,” it will overheat and trip the compressor. Check for:

• Debris or bird nests are blocking the fins.
• Objects are placed too close to the front of the fan.
• Visible layers of soot and dirt on the metal coils.

4. Listen for Unusual Noises

Your aircon speaks to you through sound. A unit that isn’t cooling often makes distinct noises that point to the root cause:

• Hissing: Often indicates a refrigerant leak.
  Clunking: Could be a failing fan motor or a loose belt.
  Buzzing: Usually an electrical issue or a failing capacitor.

A refrigerant leak is a common reason for an aircon not being cold. In Singapore’s corrosive, humid air, copper pipes can develop “formicary corrosion” over time. If you hear a persistent hissing or see ice forming on the copper pipes, you likely need a professional aircon repair.

5. Observe the “Jelly” in the Drain Line

Is your aircon not cold and leaking water? This is a classic sign of a clogged drainage pipe. In Singapore’s high-humidity environment, algae and bacteria grow inside the PVC drain pipes, creating a “jelly-like” substance.

When the water cannot flow out, it backs up into the fan coil unit. This excess moisture can interfere with the sensor’s ability to read the temperature correctly, or worse, cause the system to shut down as a safety precaution.

Symptom	Likely Cause	Recommended Action
Water dripping from the front	Clogged drain pipe	Vacuum the pipe or call for servicing
Ice on indoor coils	Restricted airflow/Low gas	Clean filters or check for leaks
Musty “sour” smell	Mould/Bacteria growth	Chemical wash required

6. Evaluate the Age of Your System

Sometimes, the reason your aircon isn’t cold is simply due to its age. Most units in aircon in Singapore households have a lifespan of 7 to 10 years. As components like the compressor age, their efficiency drops. If you find yourself calling for aircon repair every few months, the cumulative cost might exceed the price of a new, energy-efficient System 3 or 4.

In 2026, newer models offer significantly better SEER (Seasonal Energy Efficiency Ratio) ratings, which is crucial given that electricity tariffs in Singapore fluctuate based on global fuel prices (Business Times, 2026).

7. When to Admit It’s Time for a Chemical Wash

If you have cleaned the filters and the outdoor unit, but the air is still lukewarm, the internal cooling fins are likely “choked.” A standard aircon servicing involves brushing and vacuuming, but a chemical wash uses specialised solutions to dissolve deep-seated grime and mould that a vacuum cannot reach.

Statistics show that a professional chemical overhaul can restore cooling performance by up to 30% and significantly improve indoor air quality for residents with respiratory sensitivities.

Why Professional Maintenance is the Ultimate Fix

While DIY troubleshooting is a great first step, aircon maintenance in Singapore is a technical field for a reason. Modern inverter systems are complex machines with delicate sensors and volatile refrigerants. Attempting to “top up” gas or dismantle a fan coil without training can lead to permanent damage or voided warranties.

Regular, scheduled aircon servicing is the most cost-effective way to ensure you never have to deal with a “not cold” unit in the first place. It’s about being proactive rather than reactive.

The Benefits of Regular Servicing

• Lower Electricity Bills: Efficient units use less power to hit target temperatures.
• Better Air Quality: Removes mould spores and dust mites from your breathing zone.
• Prevention: Catching a small leak now prevents a compressor burnout later.
• Longevity: A well-maintained unit can last 50% longer than a neglected one.

Whenever you find yourself unsure about the health of your cooling system, Jia Xing can help with transparent pricing and NEA-certified technicians who understand the specific challenges of the Singaporean climate.

Stay Cool with Jia Xing Aircon

The heat in Singapore is unforgiving, but your aircon doesn’t have to be. By following these seven troubleshooting steps, you can save yourself a lot of stress. However, if the air remains warm and the humidity continues to rise, it is time to call in the experts.

For reliable aircon servicing, high-quality aircon installation, and expert aircon repair, look no further than Jiaxing Aircon. We pride ourselves on transparent service, technical excellence, and helping Singaporean households stay comfortable all year round.

Don’t let a faulty aircon ruin your day. Whether you need a routine check-up or an emergency repair, our team is ready to restore the chill to your home. Contact Jiaxing Aircon today for a consultation and experience the best air conditioning care in Singapore.