Guide to Choose the Right Aircon in Singapore

Air-conditioner (“aircon”) is fast becoming a necessity rather than a luxury in Singapore. Many are willing to pay more for the cool comfort. Yet, it’s still a luxury because installing aircon takes up a big chunk of the renovation budget. Depending on the number of aircon units, installation of these units easily sets you back by S$2,500 to S$4,500. Hence, it’s important to do your due diligence and decide what suits you and your budget.

Factors to consider when you buy the air-conditioner:

  1. Decide on the Aircon System
  2. Choose the right BTU
  3. Non-Inverter or Inverter?
  4. Is it Energy Efficient?
  5. Aircon Piping Standards
  6. Additional Features
  7. Warranty
  8. Shortlist the Brands
  9. Our Choice: Mitsubishi Heavy Industries

1. Decide on the Aircon System

Firstly, know where you want to install the aircon units in the house. Some may choose to install for only the master bedroom or the bedrooms. Others might want to install for the whole house, including the living room. How about you? By knowing the number of aircon units to install, you will have a better idea of the aircon system to get. 

Aircon System

There are (aircon) System 2, 3, 4, or 5 in the market. The number indicates the number of indoor units to 1 outdoor unit. 

  • Indoor Unit (also known as Fan Coil Unit) refers to the aircon unit(s) inside your house.
  • Outdoor Unit is the big rectangular machine/”box” that’s placed on the aircon ledge outside your house. Some people call it “compressor” but the compressor is only part of the outdoor unit, albeit a main component for the aircon.

So for example, a System 3 will mean 3 indoor units to 1 outdoor unit. The 3 indoor units could be all in your bedrooms, or 1 in the living and 2 in the bedrooms. 

If you intend to get 4 aircon units for 3 rooms and the living room, you might want to consider these two options:

  • System 3 + Single Split system is recommended if you plan to switch on all the aircon units at the same time. System 3 and the single aircon unit will each get a compressor. With two compressors, the price is of course more expensive than one compressor of System 4.
  • With System 4, the cooling capacity will be reduced whenever 4 or more indoor units are turned on at the same time. That’s because they share the same compressor. However, System 4 will be sufficient to keep your house cool if you do not intend to operate all the units simultaneously. In this way, you save on the cost of having an additional compressor.

2. Choose the right BTU

After deciding the number of indoor units to install, it’s time to choose the right British Thermal Units (“BTU”) for each unit. Choosing the right BTUs for your home will mean keeping cool without overloading your aircon and paying skyrocketing bills.

BTU is a unit for cooling capacity. A higher value means higher cooling power. There are 9000, 12000, 15000, 18000, 22000, 24000 and 30000.

An example of a System 4’s BTUs: 

  • 9000 BTU for each of the 2 common rooms 
  • 12,000 BTU for the MBR
  • 24,000 BTU for the living room

I found this link to calculate BTU easily: Simply input the room dimensions and approximate insulation to get results.

Disclaimer: I’m not responsible for the use of any information from the website.

3. Non-Inverter or Inverter?

Non-Inverter aircon is the conventional or “fixed speed” air con.

  • Cons: Operates at single speed and has a large temperature variation. It uses more electricity over time and is noisier than inverter.
  • Pros: Is more affordable and easier to install.

Inverter aircon is a “variable speed” air con.

  • Cons: More expensive and complicated to install.
  • Pros: Controls the speed of the compressor and changes the temperature whenever needed. This reduces electricity consumption by 30-50%. It’s more energy and cost efficient in the long run.

4. Is it Energy Efficient?

Most aircons have Energy Efficiency Ratio (“EER”) of 10. Aircon with a point higher in EER saves you 10% in electricity bills, but generally has higher upfront cost. A unit with an Energy Star has an EEU of at least 10.7.

In Singapore, EER for each air con model is found on its Energy Label, by way of ticks. The highest rating is five ticks. The annual energy cost and the annual energy consumption for the air con is also found on the Energy Label.

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5. Aircon Piping Standards

Standard piping varies from one brand to another. Here’s an example of aircon piping specifications for Mitsubishi Starmex System 3:

  1. 16mm PVC drainage pipe 
    • 16mm ensures a smoother flow of water with reduced risk of blockages.
  2. 23 SWG copper pipes 
    • SWG, Grade or Gauge is an industrial term for the thickness of the metal, in this case, the copper pipe. Generally, a thicker copper pipe is able to withstand higher operating pressure.
    • The grade ranges from G25 to G21, thin to thickest. For HDB owners, G23 (0.61mm) is usually recommended and the industry standard. If you have concealed piping, then G22 (0.71mm) is a better option.
  3. For copper pipe, 1/2″ thickness Class 1 Armaflex Insulation
    • Insulation is for covering the copper pipe to prevent further condensation (water droplets forming) on the copper pipe. 3/8″ is usually recommended, while 1/2″ is preferred for concealed piping.
    • If you are in the know, make sure the copper piping is bent with a proper pipe bender. This will lower the possibility of condensation or poor refrigerant flow.
    • Refrigerant is the working fluid for your air con. Currently, 2 types of refrigerants are used for residential units – R22 and R410A. Due to to R22’s harmful effect to the ozone layer, it is being or has already been phased out.
  4. For drainage pipe, 1/4″ thickness Armaflex Insulation
    • Some shops might recommend/offer insulation for the drainage pipe as well, but it is not a requirement.
  5. Electrical wires: Keystone or Sigma; 3C40 or 3C70 wires (i.e. 3 core 40/70).
    • Important component. Keystone, and Sigma are two reputable brands that produce Singapore-made wires. 3C40 or 3C70 wires are used to ensure that quality and safety are not compromised.
  6. Stainless steel bracket comes at an additional cost. E.g. S$150 with installation.
  7. Total piping length for System 3 is 45 metres. Additional fee for piping over this length can be at S$8/m, with maximum charge up to 15m.
Gain City’s Pricelist

You can usually upgrade the piping or insulation with additional charges. Above isthe pricelist for piping upgrades of Gain City (2017).

Truth be told, you probably wouldn’t know if you are given the correct piping and insulation. So to be on the safe side, don’t go for the cheapest supplier, but the most reputable and reliable supplier, such as Gain City. Although I have my gripes on Gain City.

TIP: HDB has a page on what to look out for when you inspect your air-conditioner installation:

6. Additional Features

Nowadays, aircons are getting more complex and come with so many additional features. Some of these sound good to have, but you might never even use them. 

Are they practical? Are they necessary? Will you be lazy to use them? Think about your usage patterns and consider if these additional features are what you want or need.

7. Warranty

Most air-conitioners come with

  • 1 year warranty (parts and labor for repair excluding servicing). 
  • 5 years part warranty for compressor.
  • For some, installer warranty of 2 years.

This warranty seems insufficient for the aircon quality these days. Hence, for the 1-year warranty, we purchased an extended warranty of 4 years from Gain City, who will be the one honouring it.

Note that the warranty doesn’t include air-con servicing, which is an important maintenance step. You can sign up for Gain city’s air-con servicing package. But given our experience with them, I will recommend you to consider other companies such as DW Aircon.

That being said, it is recommended that you change your aircon system every 8 to 10 years. This is more cost-effective than having to keep repairing and servicing the old aircon units.

8. Shortlist the Brands

After deciding on the above, shortlist a few brands to compare. This will prevent you from being overwhelmed when shopping. Moreover, each brand has many more models to choose from.

These few brands are popular with homeowners and proven in their performance.

  • Daikin has been in Singapore since 1968. They offer technological innovations and high comfort for any living space. They offer reliable high quality and performance.
  • Mitsubishi Electric aircons feature latest energy saving and silencing technologies in order to provide performance, room comfort control, and lessen environmental impact.
  • Panasonic aircons implement features like Econavi and Autocomfort, where almost anything can be set including the horizontal louvers that provide you the freedom to set what best suits your comfort level.

Our Choice: Mitsubishi Heavy Industries

System 3, 3+1, or 4?

We initially decided not to install an aircon unit in the living room. We grew up without, and survived well. Also, we didn’t think we would use the aircon often in the living room.

However, a friend said her relative regretted not installing aircon in the living room. During the haze period, she could only stay in the room with her child, for the sake of the child’s health. Shortly after, another friend told me she regretted not putting one in the living room, because there were times when the weather was really hot, but she could only make do with the fan. Another one said, the cost of installing another aircon unit at a later time would be much more expensive.

And thus, we were swayed to install aircon for the living room and the three bedrooms. We went ahead with System 4 because we didn’t foresee switching on all the units at the same time.

For an estimate, a System 4 averages at about $4,800 on on Gain City’s website, while a System 3 at about $3,500. Phew, we got to look out for promotions by the various major retailers!


We know for sure we were not getting Sharp. The aircon repair guy who repaired the Sharp aircon at our rented place told us this brand is not recommended. We should go for Mitsubishi, Daikin, and some other brands which I forgot.

We first decided on a Mitsubishi Starmex System 4, however, the salesperson at Gain City persuaded us to get Mitsubishi Heavy Industries because it was cheaper with its promotion at that time. 

In conclusion, the options out there are limitless. Keep looking, keep researching, and don’t be afraid to ask for quotation. Look out for promotions! Most importantly, ask the dealer as many questions as you want before agreeing on any deal. The aircon is going to be there for a loooong time!

After two years with Gain City and Mitsubishi Heavy Industries, what is my experience with them? Read it in “Aircon with Gain City (Review): Mitsubishi Heavy Industries“.

Drop me a message below if you have other good tips to choosing an aircon.



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