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10 Reasons Why Your Mitsubishi Aircon Not Cold

Why Your Mitsubishi Aircon is Not Cold

Is your Mitsubishi aircon not cold even though it’s running for a substantial time? Don’t panic. There are many possible reasons behind this problem. Let’s explore 10 common reasons why your Mitsubishi air conditioner is not cooling, along with the solutions.

 

Common Reasons Why Mitsubishi Aircon Not Cold

Below are the most common reasons for your Mitsubishi aircon is not cold:

1. Clogged or Dirty Air Filter

A dirty air filter blocks airflow, making it hard for cool air to circulate. This is one of the top reasons your Mitsubishi aircon is not cold. Clean your air filter a few times in a month if you are a heavy user.

Solution: Remove the filter and wash it with water. Let it dry fully before placing it back.

 

Mitsubishi Air Filter Cleaning Cycle

2. Low Refrigerant Gas Level

Refrigerant gas is essential for keeping the cooling process live. If there’s a leak or the gas level is low, the air won’t feel cold because the heat exchange process will not work. Key signs of low aircon gas level include weak airflow or ice forming on the unit.

Solution: Contact a certified aircon technician in Singapore to inspect and refill the gas cost effectively.

3. Dirty Outdoor Condenser Unit

The outdoor condenser unit releases heat from your home. If it’s covered in dirt or blocked by objects, it can’t work efficiently, causing your aircon to blow warm air.

Solution: Make sure the outdoor unit is clean and has good airflow around it.

4. Lack of Regular Aircon Servicing

If you haven’t serviced your Mitsubishi aircon in a long time, dirt and worn-out parts may be causing poor performance. In Singapore, it’s recommended to service your aircon every 3 to 6 months.

Solution: Schedule an aircon general servicing to keep your unit in top condition.

 

Mitsubishi Aircon Servicing Cycle

5. Incorrect Mode or Temperature Settings

Sometimes, the aircon is set to Fan or Dry mode instead of “Cool.” Or the temperature is set too high.

Solution: Ensure your aircon is in “Cool” mode and set to a temperature like 22–25°C for better cooling.

6. Faulty Thermostat Sensor

If the thermostat sensor is not working correctly, it may think the room is cooler than it is and stop cooling.

Solution: A professional technician can test and replace the thermostat if needed.

 

Mitsubishi Thermostat Sensor Troubleshooting Cycle

7. Malfunctioning Fan Motor

If the indoor or outdoor fan motor is faulty, you might notice weak or no airflow even though the unit is on.

Solution: This is a technical issue and should be handled by a technician.

8. Leaky or Blocked Air Ducts (For Ducted Units)

In Mitsubishi ducted aircon systems, air may not reach the room if the ducts are leaking or blocked.

Solution: A professional inspection is needed to locate and fix duct problems.

9. Compressor Issues

The compressor is a critical part of the cooling cycle. If it’s damaged, your aircon won’t cool at all. Signs include strange noises or the unit not turning on.

Solution: Call a Mitsubishi-certified aircon repair service in Singapore for compressor repair or replacement.

10. Aircon Unit Is Too Small for the Room

If the Mitsubishi aircon unit’s cooling capacity (BTU) is too low for the room size, it will struggle to cool the space effectively.

Solution: Upgrade to an aircon with the right BTU. Choose an aircon according to the room size. Seek expert advice before buying.

 

What BTU aircon should I choose for my room

FAQ

What should I do if my Mitsubishi aircon is not cold?

Start by checking simple issues like a dirty air filter, wrong mode settings, or a blocked outdoor unit. If these don’t fix the problem, contact a professional aircon servicing company.

How often should I service my Mitsubishi aircon in Singapore?

It’s recommended to service your Mitsubishi aircon every 3 to 6 months, depending on usage. 

Can low refrigerant gas cause my Mitsubishi aircon to stop cooling?

Yes, low refrigerant gas is a common reason why Mitsubishi aircon units are not cold. A leak or low gas level prevents proper cooling and should be fixed by a licensed aircon technician.

Why is my Mitsubishi aircon blowing air but not cold?

This could be due to a faulty thermostat, dirty air filter, low refrigerant, or a damaged compressor. A technician can identify the exact cause and suggest the best solution.

Is it safe to clean the air filter myself?

Yes, you can safely remove and clean the air filter yourself. 

How do I know if my aircon unit is too small for my room?

If your room takes too long to cool or never reaches the desired temperature, your Mitsubishi aircon may have a lower BTU rating than needed. Consult an expert to choose the right size based on your room’s dimensions.

What causes ice to form on my aircon unit?

Ice build-up usually means there’s restricted airflow, often from a dirty filter or low refrigerant. Turn off the unit and contact a technician to avoid further damage.

Can compressor issues be repaired?

Yes, but compressor repair can be complex and may require part replacement. If your Mitsubishi aircon compressor fails, consult a certified technician for repair or replacement options.

Why is my aircon still not cold after a gas top-up?

If the gas leaks again or the issue lies with other components like the thermostat or fan motor, a top-up won’t fix the cooling. You’ll need a full diagnostic check.

Who should I call for Mitsubishi aircon repair in Singapore?

Look for BCA-certified aircon servicing companies in Singapore that specialize in Mitsubishi units. Read reviews and ensure the technician is experienced in handling your specific model.

 

Final Thoughts

Your Mitsubishi aircon not cooling can be caused by something simple or more technical. By understanding the possible reasons, you’ll know when to fix it yourself or call for aircon servicing in Singapore. Don’t wait too long — a timely fix can save you from more expensive repairs later on.

 

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