Panasonic 8kW Split inverter system
Large open space with wall of windows to cool and heat in SE Qld. Had to fit in a narrow space above window to minimise plumbing and wiring complications.
We opted to have a device fitted through which electrical supplier can reduce the power to the unit in times of potential brown/black out, Peaksmart. This gave us something like $200 refund. Apart from issues with a faulty Peaksmart unit at installation which made air cut out often, we try to keep aircon at 23-24 in summer and 20-22 in winter. We close off all rooms we can and run only in daytime in summer. Fortunately we are able to meet the cost of our aged comfort demands.
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When operating correctly the PeakSmart device gives the network operator the ability to selectively load shed. The aircon is supposedly switched to a low power or economy mode to reduce load on the network at times of peak loading.
So far it seems to be good value with the history of load shedding indicating it is not a common event.
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We reveal the worst performing air conditioners for heating your home:
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Thanks for the latest air-conditioner review - living in Canberra, I am more interested in heating (6 months a year) more than cooling (occasionally during 2 months a year). As regards the latest review I have a few questions - hopefully someone here can help:-
Q1 - In the large category, two Mitsubishi units (DXK21ZRA-W and SRK63ZRA-W) rated highly but what is the difference between them? same price, identical specs, and use the same indoor and outdoor units.
Q2 - Given the cold weather here I was told that a de-frosting element is required - is this so? and does that significantly change the efficiency of the units?
Q3 - are there any indoor units that, mounted on a common wall, can blast out air on both sides of the wall like my gas wall furnace does, or is it always necessary to have two internal units?
Q4 - are there any split systems that can have the inside unit mounted in the ceiling and just have a ceiling-mounted outlet?
I am new to all this, but our gas heater is dying and reverse-cycle split-sytems have been recommended. For the last 45 years in the house, heating in winter yes, but only ever needed air-cooling a few days each summer (and evaporative has usually sufficed for that).
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Welcome to the community @AdrianE,
All very good questions for Choice to reply to. I moved your post here as it adds to the existing discussion.
the best answer with the most detail could lie in downloading the respective product resources from the Mitsubishi Heavy Industries site.
edit: Q3: I initially missed the context of heating two rooms and interpreted the question as blowing air to the sides, not front, of a unit. See @phbās comments in his response re multi-head systems, as well as older comments on same.
As for Q4, no recommendation implied or inferred, but cassette systems may be what you seek? A Very Short overview and generic photo. The cassettes can be too large for some residential applications but a t least some manufacturers make relatively smaller ones that could suit.
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We have recently moved to Tasmania and have also received similar advice when speaking to a local heat pumps (what reverse air-con is called in Tassie) experts (two separate ones). They say this this is important when a unit is used in sub-zero temperatures to prevent frosting up of the heat exchange unit. Without a defrosting element, a unit will reverse the heating (air condition the room rather than heat) for a period when needed as a defrosting function. This can cause the room to heat and then subsequently cool for regular short periods to defrost the heat exchange. With a heating element, this reversing is not needed.
It also increases the comfort experienced in cold weather. We have had experience of sub-zero operation of a non-heating element unit in China where the unit gets heavily frosted and then reverses to thaw out the frost. This makes heating less efficient as heat exchange efficiency is low when it becomes frosted and one has to endure very cold air flowing from the fan unit from time to time.
Both local Tassie āexpertsā also indicated that some Daikin models (ones they recommended were models starting with FTXM) are possibly one of the better units to install where it will operate in sub-zero temperatures regularly. They strongly advised against installing non-heating element units where we live (where temps are often blow zero in the morning during winter).
Further to what @PhilT has said, a fully ducted system assuming you have a ceiling cavity for ducts.
Otherwise, there are some which allow duel fan units (fan unit on both sides of the wall hanging off one compressor)ā¦but our own findings are that they cost about the same as two separate smaller units and the system can only operate in either heat or cooling modes in both rooms (for example, one room canāt be heated while the other cools).
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We lived in Canberra and had one large and one small Mitsubishi Heavy Industries air conditioners, but I canāt remember which models. I donāt recall either of them having de-frosting elements, and they worked fine even in winter.
You might be in a more exposed or more shaded situation and therefore icy-er situation than we were. Therefore I suggest that you go with what the experts tell you is needed at your premises.
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Hi Adrian
One older source on Whirlpool suggested the DX - SR were originally retail vs trade models with minor product feature differences. But identical performance and external units. Weāve installed MHI splits in the previous 2 years and found asking MHI per their contact details on the web site a good source to clarify model differences. Refer @PhilT link.
MHI should be able to comment reliably given their home market is known for snow. Our experience in colder places (NZ with snow on the ground) would say a defrosting element is a good feature if defrosting is required most nights in winter. The cold blast of air in a bedroom is enough to wake you up. The models you listed do not have this as a standard feature. Aside from Capital Hill is Canberra that cold a place?
Our observation previously based on quotes is that it was no cheaper to have what is commonly called a dual or multi head split system, compared to two smaller separate systems. Our two adjoining bedrooms could have been configured with a dual head. The multi head systems appear to miss out on the heavy discounting evident for the high volume standard splits.
As @PhilT suggested there are cassette style units and options for an enclosed ducted system. You may find these far from cost effective. We had quotes for that option when living in North Qld. It was more cost effective to buy two wall mounted split systems. It also gave us greater coverage and for the same cost a 25% greater combined cooling capacity. The one caution we received is that not all ceilings suit cassette units, and the condensate drains can be an installation concern. Not likely a major issue if used mostly for heating or cooling in a dry climate.
Weāve had 2x MHI DXK-24ZMA-S in our living areas since 2016. The cost to install including two additional electrical circuits was as nearly as great as the purchase cost. The latter was during a discount and cash back promotion. Worth looking out for.
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I am about to buy two small air conditioners. I would like the MIH or Daikin 7 star models but theyāre expensive. I have found two 5 star ones which the shop says were recommended by Choice in 2018. If thatās true I will buy them because the price is SO cheap. They are Mitsubishi Heavy Industries SRK20ZSXA-W. Lee
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Hello Lee, and welcome to the community.
I have relocated you post to the thread relating to Choiceās review of air conditioners.
Rather than trusting what retailers tell you, especially relating to a review in 2018, why donāt you have a look at the Choice Air Conditioner Review updated in June 2020.?
If you arenāt a member, have a look at the range of membership options at https://www.choice.com.au/member/already-premium-member. Consider how much money you may save by buying the right systems vs the cost of membership 
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Hi @leelee, welcome to the community.
Did you have any specific questions you needed answered to assist with making a decisionā¦such as has anyone installed the Mitsubishi aircon and what do they think?
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We have two MHI reverse cycle air conditioners in our main bedrooms, (2.5yrs old)
And larger units in our living area and kitchen, (5yrs old)
They are great. Your choice is the more efficient option of the MHI 2.0kW units.
Weāve purchased previously from The Good Guys and from Bunnings while paying our local electrician for the new installs.
The model number you have referenced is for the premium Avanti Plus range.
The technical comparisons between the current models are towards the end of the following brochure. Also the star ratings per the Australian system.
https://mhiaa.com.au/document/split-systems-brochure/
Daiken from our experience tends to be more expensive. We have chosen a supply and install from a Daikin registered agent several years back because their package price was competitive.
P.S.
Personally Iām sceptical of the 7 star marketing hype as it is not what the Australian system says.
https://www.energyrating.gov.au/document/how-read-new-energy-rating-label-air-conditioners
Make sure with your quote you are provided written technical specification of the model offered as well as the model number in full to avoid any confusion.
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I have a Mitsubishi Heavy and a Fujitsu split system in my home . Go with the Mitsubishi Heavy . Very quiet in operation both inside and out ,the outside being important if near neighbours living area . The Fujitsu would wake the dead when it gets wound up . It is also nosier inside . They are both current models and the same age .
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A guide to split-system air conditioning that looks at size, type, how noisy they are and how to save money on running costs.
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Evaporative Systems are very inefficient at cooling in coastal towns where the humidity is naturally high, all they do is increase the humidity for little cooling.My mother had one given to her, she found it to be better as a fan than evaporative cooling.I have seen them operating at inland towns (Bourke.NSW.)to be fine coolers.but most doors and windows must be open to get any benefit.They operate by using the cooling effect of evaporation of water,which is reduced as the humidity is increased, which means if the cooler increase the humidity in a room
it also reduces itās ability to cool.
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As Choiceās review of split system airconditioners is desktop based, Iām curious how you evaluate airflow / score modelsā airflow capabilities? I have narrowed down my selection to an LG and a Haier model and airflow is one of the differentiating characteristics between them so I would like to understand the data on which you have based your ratings. Are you able to explain? Many thanks.
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Welcome to the community @BirdHall,
Sometimes the raw numbers might be helpful in addition to relative āscoresā, but this link should explain the methodology.
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Thanks @PhilT for the welcome and your response. It was after reading that article that I was prompted to ask the question to understand how a desktop assessment could properly evaluate airflow performance. Perhaps it is simply the number of speed settings a unit offers? Three speeds = average score; five speeds = good score? If thatās the extent of the assessment then I wonāt be swayed by it as much.
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In this case, from the āHow We Testā, when we need an air conditioner tested, we send it to a qualified external lab. and for airflow
Air flow is a measure of how much air the unit puts out on its lowest and highest fan speeds. The lowest fan speed should deliver a gentle breeze, while the highest fan speed should deliver a powerful blast for cooling or heating the room rapidly. A model with a good airflow score has a useful range of fan settings; some models donāt (the lowest fan speed is too powerful or the highest speed too weak, or both) and get lower scores accordingly.
However, without raw data what it means could be personally subjective for individual
needs.
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Thanks PhilT. I did read that and was curious how, from a desktop test, it could be assessed if the ālowest fan speed is too powerful or the highest speed too weakā. I assume not all units are sent to a qualified external lab to test this due to cost. Maybe all those with less than 5 fan speeds are? Itās unclear. I donāt mean to be picky. Iām just trying to better interpret the airflow ratings given to different units. Cheers.
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