Doug S
Doug S · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

I am looking to purchase a MHI 6.3kW split system (as a set comprising both the indoor and outdoor units). What is the difference between the 6.3KW Mitsubishi Bronte SRK63ZRA-W and the DXK21ZRA-W?

Romeo Alfa
Romeo Alfa  

I recently purchased the 7.1 kW Brontë SRC71ZRA-W model instead of the 63 as our summers are getting unpredictably hotter, and the winters, your guess is as good as mine. No regrets in my decision as these units are very efficient and my family and self are very happy with the wise choice. I don’t need to worry about “will the home be cool enough during summer heatwave?” The difference, in my opinion, between your two models are the indoor units as they both use the same outdoor unit, and I think it could be cosmetic. My SRC71ZRA is probably more rectangular-ish than the DXK but whatever it is, you won’t go wrong with the Brontë 7.1kW SRC71ZRA. Just remember that they need to be serviced once every two years to keep them in good working condition, and if you are in Western Sydney, get your unit from Globalrez and insist on having his best installer put your unit up. Kind regards, Romeo Alfa

Doug S
Doug S  

Thank you for your reply, I have bought the MHI 6.3kW DRK21ZRA-W today for $1,628 (Northern Brisbane). Getting installed for $650 in two days. While the 7.1kW woould certainly have done the job, according to the MHI Room Sizing Chart, the 6.3kW should be sufficient for my needs and in my circumstances (44sqm).

It is replacing a working 7.1kW system (Celestial) that was installed in December 2003. Yes, this is correct, it is 20 years old and it is still working! (it did stop working once when an Asian gecko fried a circuit board in the interior unit many years ago). I attribute its lengevity to the fact it did not get that much use over the last 20 years.... because it is pretty expensive to run. I only used it when it got really hot over summer. When I installed it in 2003 I had an asbestos roof and no ceiling insulation. Additionally, the lounge room I was cooling was exposed to both the morning and afternoon sun. The temp in my ceiling space was over 70C!! So I was trying to cool my interior AND my ceiling space. Not ideal by any stretch of the imagination.

Im 2009 I had ceiling insulation installed (pumped in cellulose fibre) courtesy of the government rebate at the time. Understandbably this made a huge difference to the overall efficiency of the Celestion 7.1kW

About 3-4 years ago my asbestos roof was replaced with a metal roof. Anticon insulation blankets were placed immediately underneath the roof sheeting. I also replaced the cellose fibre with "ceiling insulation batts" (I had to as the cellulose insulation had become contaminated with asbestion during the removal of the asbestos roof). Finally, I installed two whirlybirds to ensure that any warm air in my ceiling space is removed to reduce, if not eliminatre, any heat soak into the home interior.

On the exterior I have installed external sun shades on the eastern side to stop the sun from heating the side of the house. At the same time I had the celing insulation installed in 2009 I planted a wall of golden cane palms trees along the western side of my house which are now 5 metres high and serve as a very effective sunblock. All the shading has greatly reduced the heat soak from direct sunlight, but of course does not stop heat soak through the walls (which are not insulated) from the ambient temperature.

Despite the huge improvements to the insulation of my house, the 20 year old Celestion is still expensive to run. Because it is old technology (non inverter), when it is running, it is running at 100% capacity. So I am biting the bullet and replacing it (at considerable expense).

So hopefully the 6.3kW will be sufficient and efficient enough to nake a significient reduction in running costs. I am hoping that when in use it will spend most of the time using only minimal power as the inverter technology kicks in. Hopefully I can use it more often and have it cost less.

The 6.3kW is rated to operate from 2.3kW to 7.1kW (power consumption being from 0.2kW to 2.5kW). The 6.3kW system's minimum power comsumption of 0.2kW is half that of the 7.1kW system's minimmum of 0.4kW. Only time will tell what the actual runnins costs will be. If I encounter a very hot day, the 6.3kW is actually rated to a MAX of 7.4kW

How long have you had your 7.1kW for? What are your running costs?

Incidentally, I have also purchased a MHI 2.5kW SRK25ZSA-W (installation is taking place tomorrow, $550). It is to replace an 20 year old Mistral 1.3kW split system in my bedroom that finally stopped working earlier this year at the end of summer (It has required repairs 2-3 times over the last 20 years).

I hope that that I get many trouble free years out of these two MHI systems.

Re regular servicing, Why do you think regular servicing is necessary? What exactly do you think needs to be serviced? I never had a regular service performed on either of my two split systems since being installed 20 years ago. Nor did I perform any exterior cleaning of either of the two units. All I ever did was clean the interior filters. So to me regular servicing seems a myth. If properly installed, the system will never leak gas (my 20 year old Celestion unit is proof of that).

Thanks again for taking the time to reply to my enquiry.

Kind regards

Doug

col h
col h · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

The 7.1kw model has a washable filter. Does the 6.3 have a washable filter also. I live in an area that has lots of pollen and occasional red dust blowing in from the North.

Mitsubishi Heavy Industries Air-Conditioners
Mitsubishi Heavy Industries Air-Conditioners   DM   

Hi Col, All split systems within the Avanti, Avanti PLUS and Bronte series have washable deodorising filters. You can learn more about how to wash your filters via the page below. external link  While the allergen clear filter (which captures pollen, hair and other irritants) aren't washable, you can purchase replacement ones from our spare parts supplier below.

external link 

Hope this helps however if you have any further questions, feel free to contact us via our website or 1300 138 007.

lerchie
lerchie · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

will this system be enough for lounge dining kit hall .64 sq meters. 2.4 m height ceiling insulated walls and ceilings with bradford gold 2.2 wall and ceiling batts mainly will be used in summer regards robin lerch bargara 4670

albert
albert  

It should be ok considering it is a 6.3kw. Will be on medium Alain flow setting. If 7kw unit, then low air flow setting will do.

Mitsubishi Heavy Industries Air-Conditioners
Mitsubishi Heavy Industries Air-Conditioners   DM   

Hi Lerchie, Looking at the sizing chart (https://mhiaa.com.au/document/srkdxk-room-sizing-chart/), the 6.3kW Bronte should be suitable for that space however we always speaking to a local installer who can assess the space properly and provide a recommendation.

If you visit the page below and leave some details, we'll get an installer in your area to get in touch!

external link 

clive
clive · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

Live in Yarra Valley. Current reverse cycle doesn't work if outdoor temp drops below 5C. If I knew then what I know now ......... How low can temperature drop for this unit to keep heating?

BHH4444
BHH4444 · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

Standby energy seems to be around 30W which @ 28c/kw is $75 per year. Cannot find anything on the Mitsubishi website that indicates what standby energy should be. Does anyone know what the rated standby energy should be?

Cmehono
Cmehono · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

whole house is 100sq mts in sub tropical area, are 2 of these big enough, one at each end of weather board house?

Mitsubishi Heavy Industries Air-Conditioners
Mitsubishi Heavy Industries Air-Conditioners   DM   

Hi There, I'd suggest referring to our sizing chart to give you an idea of what would size would best suit your space - external link . We'd also suggest speaking to a local installer as there are a few other factors to consider including how many windows you might have, their size and which direction they face. You can find your local installer by vising our 'Where to Buy' page and entering your postcode external link 

tony barber
tony barber · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

noise levels in dba for bronte 63kw

R.singh
R.singh  

Hi can you pls explain bit more.

Mitsubishi Heavy Industries Air-Conditioners
Mitsubishi Heavy Industries Air-Conditioners   DM   

Hi Tony, This varies depending on whether you have it on heating or cooling mode and on which setting however on the lowest setting on cooling, the 6.3kW Bronte indoor unit goes down to 25dB. You can download the brochure which includes all technical on our website - external link 

tony barber
tony barber  

thanks I will go up to 7.7 kw unit

tony barber
tony barber  

meant to s ay 7.1 unit

Peter S
Peter S · Bronte SRK63ZRA-W / DXK21ZRA-W (6.3kW)

Hi, you mentioned the total cost was $2300, may I ask how much the installation cost was as that's the unknown factor? Cheers

Sunnycoastgirl
Sunnycoastgirl  

The unit was around $ 1700 install about $ 600

Ol codger
Ol codger  

About $600 to install.

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