Please help - Air Conditioning and indoor/outdoor Lightings

Hi guys

I'm building a new home (first time). I didn't get a chance to speak with the electrician yet…

Firstly, I want to install 2 Air Conditioner in the living room and bedroom. The living room is approx 4M wide and 7M long. The bedroom is 3.3M X 3.5M

Can you please advise what sort of Air Con will I need? Is there any better deal going on? I have checked my local Harvey Norman and Good Guys, price seems very high…

Also I have been told I will need some sort of dedicated transformer per air con and price for the transformer is approx $350 each. Do I need this?

Secondly, is there a better place (on-line/in store) where I can purchase all lighting needs (indoor and outdoor). I am checking Masters and Bunnings but want to know if there is any alternatives…

I live in Brisbane.
Thanks in advance


  • +1 vote

    Might want to consider ducted a/c?

    Cost of 2 a/c units and 2 transformers could work out to close to the cost of getting ducted and you can cool/heat more areas.

    For your reference, I had a 10KW (overkill, I know) Fujitsu installed with 4 ducts and 2 zones for $5500. This was 3 years ago in Sydney, so prices prolly different for Brisbane.


      You'll need an electrical circuit added for each unit, but unless you're importing your units from the US or only have 3 phase power, you wont need a Transformer to my knowledge…
      By the sounds of it, you're looking at Split systems (ie condenser unit in the room and compressor outside with some pipes connecting the two). I'm guessing you'd only need a 2kW (possibly a 1.5) in the Lounge and a 1kW in the bedroom.

      If you're willing to spend money, you can get new hybrid evaporative/refrigerative ducted systems nowadays that are roughly as cheap to run as pure evaporatives but blow dry air.. they cost about twice the price of an air-cooled refrigerative though. Guess it depends how much you'll use it and how much you're willing to pay for electricity into the future


        Thanks, yes I'm looking for split type. Do you know where can I buy these circuits? How much they generally cost?


          Buy circuits?
          You have them installed by an electrician… a circuit is basically just a run of cable from your switchbox..

  • +1 vote

    Evaporative cooling is much cheaper to run. However, it will not work effectively on humid days.

    Considering the cost of electricity these days, i think it is something important to consider.

    Also, try to limit the use of down lights, as they use a lot of energy for the light provided.



      I'm considering LED Downlights.
      I have tried Evaporative coolers before, but didn't like it :(


      Yeah, evaporative in Brissy wouldn't be very nice, it's a southern state thing. Canberra, Adelaide and Melbourne.

  • +2 votes


    "dedicated transformer" does not make sense. Air conditioners operate at mains voltage and do not need a transformer.

    We have some experience having domestic air conditioners installed and found it rather a grubby business where the customer often ends up with a bad deal. I could go into a lot of detail, but would summarise my advice this way:

    • Don't just focus on headline price or you will be misled.
    • You need to get the air conditioning units correctly sized for the workload. Most quoters are not capable of doing this. If they think you are price-sensitive, they will quote a unit that is too small and you will have to run it flat out and cop a high power consumption, high wear, and a lot of noise. Sizing depends on your climate, thermal insulation, skylights, doorways, ceiling height, positioning, and how much noise you are prepared to tolerate (indoors and outdoors).
    • Likewise if they over-size it you will have a unit bigger than you need and will pay more.
    • Power circuit issues are important. The bigger the units, the more a problem this becomes. Over a certain (quite small) capacity, the air conditioner should have its own dedicated separate circuit back to the switchboard.
    • Over a certain capacity of air conditioner, or a certain number of units, your electricity supply authority/electrician may require that you run 3-phase power to the house. It's not that the AC units require 3-phase; it's that, to balance the load on the three different phases in the street, the authority may require different units to be connected to different phases. This can be expensive.
    • When you get a quote, make sure it is clear in writing as to what the supplier is quoting for in terms of both the AC unit and the electical wiring. I found that it is common for one supplier to quote and then give the installation to another supplier who is a sub-contractor who wants to do the job at minimum cost. If the quote does not specify wiring back to the switchboard, the installer probably just won't do it.
    • Most AC manufacturers specify both a dedicated circuit AND a dedicated circuit breaker on that circuit; be aware that you should ALSO demand a conveniently-located physical switch on that circuit. Most of the AC units sold in Australia are designed in and for colder climates than Australia (Japan, Korea) and have built-in anti-freeze heaters that keep the oil warm all the time in case it freezes in winter. In the periods of the year when you are not using them, or if you go away on holiday, you will want to physically disconnect them to stop them eating a lot of standby power. Unless they have a separate switch, or clearly-marked circuit breaker you can throw at the switchboard, you will find that you can NOT power the unit off (the remote control only puts them into standby).

    • Regarding brands, from my small survey the happiest customers I know seem to have Mitsubishi units. Less happy customers have Fujitsu, Daikin, Panasonic. This is my own observation; do your own research (but most people you ask won't have a clue if they've been done over or not).

    • My last experience was with Daikin. We got done over in every way possible. We asked the dealer quoting "will there be a dedicated circuit and circuit-breaker ?" and were told "that's up to the installer", which turned out to be a lie, but we were not able to know this in advance.

    The installer installed neither, but just lazily hard-wired the AC unit to the most heavily-loaded circuit in the house, the kitchen circuit, and dumped a pile of manuals on the table as he left. Those Daikin factory manuals (which I couldn't read until after he left) clearly specified that the unit must have separate circuit, circuit-breaker, and electrical switch, but it wasn't done.
    We called the dealer and installer and both refused to do anything, saying that the manual only applies to Japan and in Australia they ignore it. We called the Daikin "company" to find that, like many large Asian suppliers, they had no branch nor subsidiary in Australia and the warranty and installation standards were policed only by an Australian agent trading under the Daikin name, and this agent had no interest in customers, but backed up whatever the dealer did. (Customers only buy once; dealers are repeat customers. Guess who wins.) Both the dealer and the installer were official Daikin suppliers. Short of writing to Japan, we had no rights. Consumer regulators were not interested; it was too technical for them.

    By experience we then also discovered that Daikin had fudged the specifications and the machine would only automatically run on 3 out of the 5 available fan speeds, so that it would meet noise level specifications as being "quiet", but it was hopelessly under-powered on anything other than the maximum fan speed (which we are obliged to set manually - the thermostat won't do it) at which speed the unit sounds as if it is "blowing a gale" and its plastic grilles rattle. The noise is bad. To cap it off, a large number of similar Daikin units suffered a total failure of the main circuit board, including ours, and were subject to a recall and repair.

    Daikin touts a sort of "magic eye" that is supposed to sense when you are in the room; the machine is supposed to relax to save power when you are absent and work a bit harder when you are present. We found this more than useless; it seemed to be faulty design. On reverse-cycle, when used for heating, more often that not when the room is unoccupied we can hear it howling away and when we enter the room, the machine switches off! Maybe this is another noise abatement measure. We again checked with the suppliers and were assured that it was working "normally". It's a gimmick not worth having.

    For us, Daikin was a bad experience, but, for all we know, maybe others are like this too.


    lepenseur, thanks Heaps for your suggestion, much appreciated
    I did contact again, it was actually not a transformer (I misunderstood) - its call an isolating switch…

    I will follow-up your suggestion, many thanks

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