What Sort of Air Conditioner Should I Buy?

Choosing the Right Air Conditioner for Your Needs

When it comes to selecting an air conditioner, there are lots of factors to consider. Your location, home design, ownership status, usage habits, and budget all play crucial roles in determining the best unit for you. Often conventional wisdom is not actually correct. This guide will help you navigate these considerations to make an informed choice.

Consider Your Location

The climate of your area significantly impacts your air conditioning needs. For instance, in Adelaide, where the climate can be both hot in summer and cold in winter, opting for an air conditioning unit with effective heating capabilities is essential. A reverse cycle unit (heat pump) can help minimize energy use, as more energy will likely be used for heating during the colder months than cooling in the hotter months.

Assess Your Home's Design

The size and layout of your home are important factors in choosing an air conditioner. If your home is energy-efficient with good insulation, a smaller unit might suffice. Conversely, larger homes or those with poor insulation will require more powerful units to maintain comfortable temperatures.
Additionally, your home's layout can affect whether zoning is possible. Zoning allows you to cool or heat individual rooms or areas, which can significantly reduce running costs. For instance, you can cool only the living areas during the day and the bedrooms at night, rather than the entire house all the time.

Home Ownership Status: Renting vs. Owning

Your home ownership status also influences your air conditioning options. If you own your home, you have the flexibility to install permanent fixtures like ceiling fans, wall splits or ducted systems. However, if you rent, you might be restricted to portable air conditioners or fans. While these options do not perform as well as permanent installations, they offer the advantage of being movable when you relocate.

Usage Habits and Household Size

Understanding your usage habits and household size is crucial in selecting an appropriate air conditioner. For smaller households, a 'heat refuge'—a single room with a high-efficiency air conditioner—might be adequate. This approach allows you to cool just one room, reducing energy consumption.
On the other hand, larger families may need more extensive cooling solutions to ensure comfort for all members. In such cases, wall splits or ducted systems could be more suitable, depending on your budget and home design.

Evaluating Different Air Conditioning Systems

Several types of air conditioning systems are available, each with its advantages and drawbacks. Here's a brief overview of the most common options:

Wall Split Systems

Wall split systems are popular due to their efficiency and flexibility. They consist of an indoor unit and an outdoor unit connected by refrigerant piping. Wall splits can be installed gradually, allowing you to spread the cost over time. They offer good temperature control and are more energy-efficient than portable units or ducted units. However, installation requires a refrigeration mechanic or appropriately qualified electrician, and they are more permanent than portable options.

Ducted Air Conditioning

Ducted air conditioning is often seen as a premium option. It includes a central unit connected to various ducts throughout the house. This system allows for whole of home cooling and heating. However, it has several significant drawbacks, including:

• less effective temperature control compared to wall splits unless you can afford a system with individual room control. This is particularly a problem with two story homes or homes with extensions.
  • ​Potential to get cold feet hot head syndrome in winter, particularly with high ceilings or a poorly insulated house.
• higher energy use and cost due to:
  • heat gains from the ductwork located in the hot roof space
  • the fact that there is a minimum area that can be cooled
  • heat is picked up from the return air path
  • I have had clients spending more than $6,000 per year on energy costs for a ducted system, even with solar.
• Ducted systems are also more expensive to install and maintain.

Evaporative cooling

Although I used to design evaporative coolers and cooling systems, I no longer recommend them in most cases, unless it is to replace an existing system that you are happy with.
The reasons are:

• The climate is getting more humid and so they are less effective.
  • Because of the increased humidity, the risk of getting mouldy leather has increased.
• The performance of good reverse cycle air conditioners has improved so much that although they still use more energy for cooling, the benefits for winter heating outway the extra cooling energy
  • Even if fitted with non-return dampers they are still a major source of air leaks unless you seal each grille during winter. The cost of the winter heat loss will in most cases equal the summer savings.
• They are usually paired with gas heating (or electric fan heaters) both of which cost substantially more for heating than a reverse cycle air conditioner.

Portable Air Conditioners

Portable air conditioners are a good option for renters or those needing a temporary solution. They are easy to install and can theoretically be moved from room to room (although in practice because you need a vent kit and where you put it is where it will stay). However, they are generally less efficient and powerful than other systems, making them suitable for small spaces or occasional use. They are more effective in the evening and at night.

As one salesman I knew would say:
'What have you got now?' 
The answer would be 'Nothing'
His response would be 'Well this is better than nothing.' 
In other words, only choose a portable air conditioner if it is the only option. 

Fans

Although not air conditioners, fans can be an important part of your cooling strategy. If your home is reasonably well insulated, wall splits in the daytime areas and fans in nighttime areas can provide comfort on all but the hottest nights while achieving low energy costs. Good quality ceiling fans can quietly reduce the perceived temperature by 2-3 degrees. 
Pedestal fans, although not as quiet, can be very cheap and still give a good level of nighttime comfort.

Choosing the unit

If buying an air conditioner, you need to consider the energy efficiency as the running costs will exceed the purchase cost after a few years. Check the star rating on the government web site Energy Rating - Air Conditioners - AS/NZS 3823.2 .
Generally you should choose the best heating star rating you can afford and aim for at least 3-stars heating, even if you are actually purchasing it primarily for cooling as you will use more energy for heating than cooling.
It is important to choose the correct star rating as air conditioners assessed to the old rating will appear to have a higher star rating. If you are in Adelaide compare the ‘SEER Heating Star Rating’ for the ‘mixed zone’ see below.

Budget

Your budget will inevitably play a significant role in your decision-making process. While ducted air conditioning systems can be whole of home, their poorer temperature control and high installation and running costs reduce their attractiveness.
Wall split systems offer a more cost-effective alternative, as they can be installed incrementally according to your budget. the incremental nature means you can install one, while you upgrade the thermal performance of the house and see if you need more.
​In most of Australia, reverse cycle air conditioners make sense as they are the cheapest form of heating.
Portable air conditioners are the cheapest option upfront, but their lower efficiency and higher running costs can make them more expensive in the long run. Heat pumps, while having a higher initial cost, can offer savings on energy bills over time due to their efficiency.

Seeking Independent Energy Efficiency Advice

Given the many variables involved in choosing the right air conditioner, seeking independent energy efficiency advice is highly recommended. A home energy efficiency assessment will save you much more than the cost and ensure you don't waste your money.
can assess your home and provide tailored recommendations based on your specific needs and circumstances. This approach ensures that you choose the most suitable and cost-effective air conditioning solution.

Conclusion

Selecting the right air conditioner involves careful consideration of various factors, including your location, home design, ownership status, usage habits, and budget. By assessing these elements and seeking professional advice, you can make an informed choice that meets your cooling and heating needs efficiently and economically. Whether you opt for a portable unit, a wall split system, or a ducted air conditioner, the key is to match the system to your specific requirements for optimal comfort and energy efficiency. 
Consider getting a home energy efficiency assessment. It will save you much more than the cost, and ensure you achieve your goals quicker.
​If you have questions Contact us.