Mitsubishi Electric Asia Pte Ltd


Frequently Asked Questions

Air Conditioner

The indoor unit is emitting a bad odour
The indoor unit does not produce odour by itself. Generally, the surrounding smell is absorbed into the fan coil unit and discharges out with the air flow.

In many cases, air conditioner blows out bad smelling air because of mold and mildew accumulation at the cooling coil and drain pan. Air circulation resulted in small particles impurities in the air attach themselves to the fins or around drainage areas.
General servicing is required in such cases to eliminate the root cause of smell.

The indoor unit is noisy
The line flow fan may have accumulated too much dirt. It is recommended to carry out general servicing.

Poor Cooling
This could be due to insufficient refrigerant or lack of servicing.

If your air conditioner is low on refrigerant, either it was undercharged at installation or it leaks. If it leaks, simply adding refrigerant is not a solution. A pressure test to determine the leak should be conducted, fix any leak, test the repair, and then charge the system with the correct amount of refrigerant.

If it’s due to the latter, general cleaning is needed to improve the performance of the air conditioner.

Dew prevention
During COOL or DRY operation with the vane angle at Angle 4 or 5 when the compressor’s cumulative operation time exceeds 1 hour, the vane angle automatically changes to Angle 1 for dew prevention.

The fan coil is noisy and the air blown out is weak
This can be caused by the following:
• The cooling coil may be choked with impurities.
• Dirt had clogged up on the line flow fan after a period of time.
• Filter is dirty.
It is recommended to do general cleaning to improve the performance of the air conditioner. For severe blockages, please engage a professional to perform chemical washing for it.

The air blowing out from the indoor unit is irregular
A dirty coil affects the air flow of the indoor unit. Please consult a cleaning specialist.

When the fan is set at "Hi" fan mode, the indoor unit is noisy
The "Hi" fan mode is for rapid cooling and some noise is expected.
It is recommended to switch to "medium/low" fan mode after room temperature is achieved and noise will be minimized.

The outdoor unit is noisy
It may be due to the following:
• Refrigerant pipes may be too near to each other
• Screws may not be properly tightened.
• No rubber pads were placed underneath the outdoor unit

The indoor unit is not cold when turned on
The indoor unit may be too dirty or has a shortage of refrigerant.

The indoor unit is too cold
The temperature setting on your remote controller is too low.

The indoor unit cannot be switched on
It may be due to the following:
• The remote controller may be faulty.
• The receiver/infrared ray at the indoor unit may be faulty.
• There is no power supply to the indoor unit.
• The battery of the remote controller needs replacement.
• Please check the power supply source whether there is any trip.

It is recommended to replace any of the above items.

3 out of 4 indoor units are cold without switching ON
• The connecting wires / refrigerant pipes may be connected incorrectly.
• LEV coil/valve may be faulty.

Water is leaking from the indoor unit
This is normally caused by blockage in the drainage pipe. It is recommended to do general servicing for the air conditioner.

Water is leaking from the outdoor unit
This is normal. During cool and dry operations, pipe connecting sections are cooled and causes water to condensate. It is recommended to install the recommended drainage kit to prevent water dripping to your neighbour's outdoor unit.

There is some ice formed on the indoor unit.
It may be due to the following:
• The refrigerant gas may be insufficient.
• The air filters, line flow fan or cooling coil may be dirty.

Is there any special filter that can be used against haze?

How much savings do I get by using inverter type of air conditioners?
Generally, the estimated savings is more than 30%.

What is the small piece of white filter found in the indoor unit used for?
It is used to improve air quality.

Is it possible to re-use existing piping?
Yes. Flushing of the existing pipes and vacuuming must be performed.

What is the electrical consumption for air conditioner per day?
It depends on the set temperature, running hours and the electrical tariff charges.

How long should I need to clean or replace the anti-allergy enzyme filter?
It is recommended to clean quarterly. Replacement is required for wear and tear.

How to use “dry” mode of the remote controller?
It is used on a rainy day or when the relative humidity is high. The fan occasionally stops to improve the removal of moisture in the environment.

How do I set the daily timer of the remote controller?
Please refer to the User Manual. The remote controller is of “daily type” setting and is required to program current time first, followed by start and stop button of the timer.

Why does the indoor unit indicator light changes from 2 to 1 light after a certain time?
This shows that the room temperature has reached or close to the desired temperature.

Can an individual indoor unit be tied to operate only from an individual remote controller?
Yes, please bring your remote controller to us for modification.

Why is there no temperature shown on the remote controller?
The temperature will only be shown in cool mode setting or the remote controller is faulty.
It is recommended to purchase your remote controller with us if it is faulty.

At low speed, it takes a long time to reach a temperature of 20c.
Please switch to “Hi” fan speed for faster cooling.

Is aluminium piping allowed?
No, we do not guarantee on the air conditioning system. It is highly recommended to use copper piping.

There is rust on the outdoor unit.
Rust is not covered under our guarantee terms and conditions. We do not provide paint works for the rust.

Can indoor units be installed in a hair salon?
Due to the compact high efficiency design of the heat exchanger, the use of wall mounted fan coil unit are not recommended. Only ceiling concealed or suspended units is recommended for such installation.

Why are the 2 lights of the fan coil unit blinking?
They are blinking continuously as the safety switch located on the left of the louvers is not properly locked in. It acts as a safety device and does not mean that your unit is faulty. Ensure that the safety switch is properly secured in position and it will stop blinking.

The veg compartment is not cold.
Too much food inside the refrigerator compartment may blocked off the air circulation to the vegetable compartment.

The refrigerator compartment is too cold.
The damper thermostat is faulty or obstructed.

There is water dripping inside the refrigerator compartment.
There may be a blockage in the drain hose.

Water stays at the drain pan behind. Is it normal?
It is normal to have defrosted water collected at the drain pan. It is only abnormal when the water overflows.

The fridge is smelly
The fridge does not produce smell by itself, it is mostly caused by the food stored at the compartment.

The ice maker is not making ice.
• The ice maker is faulty.
• No water in the water tank.
• Ice making function was turned off.

One fridge door will be opened whenever the other one is closed.
• Too much food obstructing the doors from closing properly.
• Refrigerator should be adjusted slightly inclined towards the back.
• Alignment with floor level.

What is the temperature for soft freezing and usage?
It is about -7c for food stuff.

Why are all the sides of the refrigerator hot while in operation?
They are anti condensation pipes to prevent condensation building at the cabinet.

What is the required space for a built in refrigerator?
There must be a minimum of 20mm gap on the sides and 100mm gap above the refrigerator.