Frequently Asked Questions About Aircon

Air conditioner

In this FAQ, we will answer a variety of questions coming from homeowners in Singapore, ranging from what aircon professionals provide, to the details of aircon chemical flushing and whether you should do it yourself.

Before we proceed, if you are a resident in Singapore, you can read up on HDB guidelines on aircon installation and servicing.

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General questions

General questions

What do aircon professionals provide?

Every aircon servicing company offer different services. As different brands of aircon may require different know-how to repair/service, it is important to clarify their services before engaging them.

The most common types of services are:

  1. Regular contract servicing/maintenance
  2. Air conditioner installation works
  3. Air conditioner repairs
  4. Chemical overhaul
  5. Chemical cleaning / Chemical flushing/ chemical wash
  6. Evaluate and advice
  7. Aircon installation
  8. Diagnostic and inspection
  9. Gas top-ups and inspections
  10. Troubleshooting

Helpful read: Aircon Cost Guide and Estimate in Singapore

Why is the aircon not cold?

This can be an annoyance for everyone, especially when the afternoons are swelteringly hot and the aircon is not cooling enough. The main reasons why the aircon is not cold are as follow:

  1. The filter is dirty
  2. Temperate settings of an air conditioner are too high
  3. Area capacity for air conditioner cooling is too large (i.e. not enough aircon units to cool the entire)/ the air conditioner installed is under-sized
  4. Thermostat is faulty
  5. Not enough compressor gas
  6. Refrigerant leakage
  7. Components of aircon may be faulty
  8. The indoor fancoil is dirty resulting in weak dissipation of cool air.
  9. The outdoor condenser is dirty resulting in incapable of producing cooling refrigerant.
  10. There may not be enough refrigerant in the air conditioning system.
  11. There might be some problem with the air conditioning system resulting in non-continuous operation of the system.
  12. Check if the door and windows are shut.

To know about what is causing this issue, you can check out this article listing several reasons.

Regular aircon servicing in Singapore of at least once per year is advised to maintain the working conditions of the air conditioners to ensure your aircon is working fine and is cold all year long.

Why does aircon leak water?

Leaking aircon is a perennial problem faced by households every few years. The exact cause can only be determined and identified by an aircon specialist, and such reasons for aircon leakings are as follows:

  1. Clogged drainage pipe: Normally, the air conditioner’s water will condensate inside the fancoil. This will usually be released in the drainage pipe. If the drainage pipe is clogged or choked then water will start leaking. General aircon servicing normally involves the vacuuming of the drain pipe which may rectify the choked pipe problem.
  2. Wear and tear of the aircon
  3. Poor installation of aircon
  4. The gradient of the piping between the fan coil and drainage is too gentle causing leakage

We have covered in detail the various reasons why aircon leak water in this article.

Why is that water dripping from the outdoor condenser/compressor?

Aircon water leaking as a result of outdoor condenser or compressor is normal as condensation happens when condenser cools the surrounding warmer air.

We have covered important information you need to know about aircon compressors in this article.

Why does the aircon produce a foul smell?

There may be several reasons for this:

  1. The surrounding smell may be absorbed into the unit. An example could be small from furniture, cigarettes, food.
  2. Bacteria formed by microbes in the warm dark humid environment in the indoor fan coil unit may be causing the smell. Sometimes when the smell is very bad you may need a more intensive chemical treatment to rectify this problem.
  3. Pollutants like smoke from cigarettes or haze could be absorbed by the unit. The solution to this is the intense chemical treatment of the air conditioner.

Why is my aircon noisy?

There could be several reasons:

  1. Vibration noise resulted from a dirty indoor fancoil/ outdoor condenser.
  2. Noisy draft resulted from dirty indoor fancoil
  3. Some components in the air conditioning system may be mounted loosely
  4. Faulty parts in the air conditioning system.

Why is the aircon not working?

One common reason is that electrical power is not being supplied to the air conditioner. It could be loose wiring or that the electrical panel is malfunctioning. A qualified professional should be engaged for the repair if it is more complicated than a simple repair.

When do I need a gas top up and or inspection?

Gas top-ups are absolutely essential in the case of unsealed leakage. It is imperative to seal the leaking areas before topping up the gas. Once completed, you will not need to top up gas until the same issue occurs again. A number of factors may lead to gas leakage.

These may include improper installation, poor quality copper pipe and more. We recommend you to ask an air con professional before attempting any gas top up on your own.

You can find more aircon gas top up professionals in our directory.

How often should I service my aircon?

The basic maintenance that is recommended is the cleaning of the air filter and outer panel of the air conditioner every 2 weeks. This will helps to improve the air conditioning of the room.

For a more in-depth servicing, it is recommended to service 3-4 times a year for residential properties, and once a month for commercial. Please seek the assessment of a qualified technician.

You can find the cost of aircon maintenance in Homees cost guide.

What does regular aircon contract servicing/maintenance include?

Regular contract servicing/maintenance. Includes:

  1. Cleaning & checking the air filter, front panel & cover
  2. Checking purifying filter
  3. Cleaning & checking indoor evaporator coil
  4. Cleaning & checking indoor drainage tray
  5. Vacuuming of the drainage system
  6. Checking fan bearing and lubrication (if necessary)
  7. Checking compressor suction and discharge pressure

What is Aircon Trunking?

Aircon trunking refers to the piece of white plastic casing that covers the electrical cables of the unit. Alternatively, it is also called aircon casing and aircon cover.

Aircon trunking is usually made of Polyvinyl Chloride (PVC) and acts as a protective layer between the air conditioner and the area outside of it. This helps to preserve the lifespan of your air conditioner unit and, in turn, save on your maintenance costs.

How to hide aircon trunking

To maintain a clutter-free and aesthetically pleasing home, some homeowners may consider hiding their aircon trunking. After all, an open mass of wires would look awful in a clean and cosy home.

As such, a way to hide your aircon trunking would be to design grille covers for them. By keeping the aircon behind an open-section and covering it with grills, you achieve two things – your aircon looks less obtrusive while cool air is still able to permeate the room.

Similarly, installing your aircon in a shelf-like area on your wall can also be a great way to hide your aircon trunking. If the shelves are about the same depth as your aircon, that’s even better. The cool air from the aircon will be able to reach every part of the room.

Alternatively, you may want to conceal your aircon within a false ceiling, which is a great way to hide almost the entire aircon trunking.

Another way to hide your aircon unit comes in an almost paradoxical way – leave it in the entrance of your corridor or passageway. While it lies in plain sight, the aircon unit won’t appear obstructive.

What causes aircon condensation?

When installing aircons, insulation materials are used to lower the chances of condensation in the aircon trunking. However, if the insulation is not of sufficient thickness, aircon condensation will happen.

Alternatively, if the joints of the aircon trunking are not properly fixed in place, moisture will also seep out via the aircon joints when aircon condensation happens. In more serious cases of water leaking out, some people may mistake the moisture as aircon pipe leaking.

In this scenario, the aircon trunk may need to be reinstalled. You may want to engage a professional aircon installer to do so safely and securely.

What benefits should I expect if I service my aircon unit? What happens if I do not do any aircon servicing?

The benefits are as follow:

  1. Improved efficiency: Regular air conditioner servicing help improve the efficiency of the air conditioner unit. This saves electricity and costs over time (with lesser repairs needed and it working longer). The electrical consumption of the air conditioning equipment will be lower.
  2. Cooler rooms: Air conditioner units that are regularly maintained perform at their optimum capability leading to a cooler room.
  3. Lesser repairs and longer lifespan of air conditioner: If you don’t maintain your air conditioner regularly, like all products it will not last as long as it possibly can. Problems such as leakages will be minimized.

We strongly advise you to get the aircon unit regularly serviced. Find more reviewed and rated professionals from our platform and engage a reliable aircon installation company.

Can I DIY the general aircon services myself?

Washing filters and cleaning the fan coil cover can be done by yourself, but it is best to contact your air conditioner servicing provider to ensure your aircons are thoroughly serviced and checked.

You can check out how to DIY clean the aircon yourself in our article.

Why must the fancoil unit be dismantled for chemical cleaning/chemical washing?

By dismantling the fan coil unit, the air conditioning individual components can be washed thoroughly, as compared to just inserting a water tray to wash away the chemical.

This will help better clean the unit and also not leaving behind chemical residue that may lead to the corrosion of the fan coil.

It is best to engage an aircon chemical wash professionals in Singapore.

How should I know if my unit is set to its optimal temperature?

An air conditioner’s optimum temperature is 25-26 degrees. If you set it at 1 degree higher, this could lead to an increase in operating cost at up to 15%.

Why does ice forms on the copper pipes of the condenser (outdoor)?

Ice forms for 2 primary reasons:

Ice forms on the copper pipes of the condenser if:

  • The gas in the system is insufficient
  • Ice-formation on the suction pipe could be caused by a dirty fan coil unit or, a dirty filter or, the indoor unit blower is not rotating.

What should be done if there is an aircon refrigerant gas leaking problem?

A trained technician should perform pressure testing to trace and repair the leakage point. Upon completion of the leaking repair, a correct amount of refrigerant gas should be topped up.

What is the advantage of Air Purifying Filter and how often do we have to replace it?

Air purifying filters can remove smoking odour, human smell, impurities and harmful particles in the air condition space. The newest model of air conditioner comes with an air purifying filter. Leaving dirty air purifying filter in the air conditioning system will affect its cooling performance.

Its recommended that the purifying filter is replaced every three to six months.

Why should I sign an aircon servicing maintenance contract?

Having regular service maintenance importantly ensures you have a healthy living environment. The second benefit is that it usually prolongs the lifespan of your aircon.

Lastly, having regular maintenance with an aircon servicing company allows you to buy packages at a discount which could save you more money over time.

What should I look out for when buying an aircon unit?

There are 4 areas of consideration to choose an aircon and aircon services in Singapore:

  1. Areas required for air conditioning.
  2. Cooling space and power required.
  3. Determine the brand and type of aircon you desire, such as aircon servicing efficiency.
  4. Budget for an air conditioner.

Which air conditioner brands are better?

Consult aircon installation companies in Singapore and ask them for their opinions regarding your air conditioner installations.

Talk to our air conditioner professionals in Singapore and ask them for their opinions regarding your air conditioner installation.

What is the average lifespan of a residential air conditioner?

With professional aircon servicing and installation, an aircon can last about 6-7 years.

What is the warranty period of aircon units?

In the market, the norm is that for residential units, the warranty period for the spare part is 1 year and for the compressor is 5 years, depending on the supplier/contractor.

What is the difference between a window unit and a split system?

A window unit is a single unit that is installing in any wall or window opening. All the components required for the aircon to function is packaged in it, and no piping in required for its installation.

A split unit consists of an outdoor (external) compressor unit and an indoor (internal) fan coil. The fan coil unit (FCU) helps to cool the room while the external compressor cools the surrounding air and provides it to the FCU. Hence, piping is required for installation.

A multi-spilt unit consists of an outdoor compressor and more than 1 FCU. It enables the cooling of multiple rooms simultaneously.

Performance-wise, there are two main key differences between a window unit and a split/multi-split unit are:

  1. Window units generally require more electricity to operate, hence are generally incur a higher monthly electrical bill.
  2. Because of the way a window unit is designed, it generates more noise during operation.

What does an inverter aircon mean?

An inverter aircon consists of an inverter circuit that helps to balance and regulate the workload of the compressor. As such, the compressor will work more efficiently and helps to reduce the electrical bills.

How do I determine the power capacity required?

Generally, use the simple equation below to calculate the amount of power required for a room/space:

Area (length x breath) x 65 = BTU/hr

Example: Room (10 ft x 10 ft) x 65 = 6500BTU/hr

Take the BTU/hr and multiple it with 0.000293 to convert it to KWh (energy unit used in Singapore utility system)

This means that in 1 hour, aircon will require 6500BTU of energy which is about 1.9KWh (6500 x 0.000293) of energy.

You can read more about calculating aircon BTU in our article here.

Why does the air-con switch OFF by itself and why is the aircon indicator light blinking/flashing?

The blinking/flashing of the indicator light usually indicates that there is a fault with the air conditioning system, leading to the problem of the air conditioner switching off by itself. It is a protective function to prevent the air conditioner from further damage.

A qualified aircon technician is needed to diagnose and repair the indicator light problem.

Why does the aircon switch ON and OFF by itself?

This occurs when there is a fault with the indoor electronic circuit board. Damage to the circuit board causes it to lose its operational control, as it is the one that controls the operation of the indoor fan coil. A repair or replacement of the circuit board is necessary.

Why the air conditioner cannot be switch ON using the remote control?

The fault might lie in the remote controller or the indoor printed circuit board. Try the remote controller on other fancoil and if it works, your remote controller is fine. If the fault lies in the printed circuit board, you need to engage an aircon repair technician to do a repair on the printed circuit board.

Why is the fan coil unit still operating when the condenser is not?

The fan coil unit and condenser operate independently. The fan coil transfers the cooled air from the condenser to your room while the condenser cools the air. Hence, even if the condenser is faulty, the fan coil will transfer the air from the condenser to the room.

Do we need to service the Condenser (outdoors)? If, yes, how often?

It is recommended to service the condenser (outdoor air conditioning unit) at least once a year to make sure the air circulation of the unit is not blocked. Having a blocked condenser will affect the cooling efficiency, a shorter compressor life and higher electrical consumption.

Sometimes, it is subjected to environmental condition, which requires qualified aircon servicing companies to give recommendations.

What is pressure testing of the air conditioning system and why it is needed?

Air conditioning refrigerant leaking in the system can be suspected when ]the refrigerant gas in an air conditioning system depletes away and the air conditioner needs to regularly top up refrigerant gas.

Pressure testing work will help to identify which is the leakage area. Normally high pressure is induced into the condenser, fancoil and refrigerant piping to identify where is the leakage. Further repair work will be quoted upon identifying the leakage area.

Note: Pressure testing work is a testing process (not repair work) to identify the leakage area. This work will not be able to rectify the fault but it’s a necessary process to define the scope of repair deriving from the result of the testing work. The leakage area defined herein is an indicative section of the refrigerant system.

What types of air conditioners are there?

The different types and brands of air conditioner include:

  1. Window air conditioner
  2. Casement air conditioner
  3. Residential split air conditioner
  4. Commercial air conditioner (Daikin VRV system)
  5. Portable aircon

You can talk to aircon installation professionals and find out the differences in the brands, or if you’d like you can read our cost guide on the cost of aircon servicing and aircon installation in Singapore.