Thread: Ducted whole house or wall splits ?

Originally Posted by rick130

Only work properly in areas of low humidity, (don't use anywhere near the coast, and that includes any coastal strip up to the divide along the eastern seaboard) and will work very well if whoever engineers it works on quite a few air changes/minute.

You hit the nail on the head. Reviewing our (dying) evap. unit, it's the Breezeair ES 210, and for our size house it is in the middle of their 'Air-changes' range.
But, if you consult some HVAC engineering tables etc, it's barely marginal, and really, we could have gone with 2 same or smaller units to do the whole house. - Effectively... Some Big Box Stores have massive evap units which work acceptably in our high(er) humiditiy levels, but the amount of air they pump through is equally impressive!

The ducted-DAIKIN is leading the pack at the moment... despite my philosophical attachment to a new stepper-motor Breezeair simply for cheaper overnight running... (bedrooms only)
SWMBO 'flexible', but #1 son is 101% Ducted...
-- He's bigger than me...

Originally Posted by superquag

You hit the nail on the head. Reviewing our (dying) evap. unit, it's the Breezeair ES 210, and for our size house it is in the middle of their 'Air-changes' range.
But, if you consult some HVAC engineering tables etc, it's barely marginal, and really, we could have gone with 2 same or smaller units to do the whole house. - Effectively... Some Big Box Stores have massive evap units which work acceptably in our high(er) humiditiy levels, but the amount of air they pump through is equally impressive!

The ducted-DAIKIN is leading the pack at the moment... despite my philosophical attachment to a new stepper-motor Breezeair simply for cheaper overnight running... (bedrooms only)
SWMBO 'flexible', but #1 son is 101% Ducted...
-- He's bigger than me...

If the ducted AC unit is designed and installed correctly,it will operate at its most efficient during the night

From my personal experience (for what is worth:

- Spilts give you redundancy if you have an issue and at least parts of your house will be cool.

- we rented a house with ducted and were staggered by the cost of running it. That was 8 years ago granted with a 2 year old system. Maybe also part of this is that with the splits we feel more compelled to turn off units we aren't using.

- we bought a house 8 years ago with three Daiken units. They are all inverters so obviously not much older. Two have failed. One we spent almost $1500 to fix for it fail the next summer. My lesson. Don't repair out of warranty. Replace.

- we have three Futijuis for about 8 yrs. No issues with any. Probably jinx myself now. I feel the same way every time I mention on this forum my Defender is now 18 months old without a single warranty issue!

- also depends on your house. We have an old Edwardian house. We tried to get quotes for ducted and everyone warned us our ceilings would potentially crumble and fall in (due to the horse hair plaster) and they wouldn't guarantee their work. Also we have found that due to the old fashioned design with the centre corridor and bedrooms coming off we have not needed to put AC in our bedroom. Every other room has it but due to the vents in the ceilings of the rooms and between then and the corridor and also near the skirting on the floors the hot air is drawn out naturally and the cold circulates. Of course we also find this means our house can be quite cold in winter but it does make you wonder why we can't do more of this design nowadays and then perhaps have some simple system to shut off the vents come winter.

'Redundancy' is a beautiful word.

I'm concerned that you've had so many failures in the DAIKIN units, reputed as being 'better than average'. (than cheep Chinee...)
And I'd agree, replacing rather than 'repair' would have to be better if for no other reason than a full warranty on ALL the bits in the (replaced) unit.

SWMBO is strongly leaning towards updating our rooftop evap. box with the newest model, thus giving us economical overnight running plus 'air-changes' built into the operation. Complementing this with a large wall-split in the Family Room for the humid weeks, AND for heating in winter.- Most important!

Bedrooms don't really need much cooling during the day, only at night. Nor is heating them as good as a warm bed!

I like the idea of utilising the 'waste' evap. air and exhausting it into the roof void, thus keeping this space cool(er) during heatwave conditions...
Having ceiling insulation retards the rate of heat travel - from inside the 'attic' down through the plaster and into the house... it does not stop it.

My approach is to keep this void air as cool as possible, and I've noted 15+ degrees drop just by doing this. (I've got a thermometer up there, above the 1 sq.metre manhole in our store-closet.)

Regulation of this 'void' air temp. is, IMHO, critical in summer to keep your A/C from being overworked/running co$t$... Best way - apart from forcing cool air up there - is 'whirlybirds' and eaves vents. With your older-style house I'm guessing clay or concrete tiles (?) which do a great job of storing heat...

According to the large DAIKIN re-seller I chatted with yesterday, their latest/better wall-splits are now using the more efficient hydrocarbon-based gas, the ducted ones still using R410. Efficient, but not quite as good as the HC...

DAIKIN are built in Taiwan under Daikin management, Hitachi (cheaper than Daikin but still sold/supplied by this company, from Malaysia again under Jap. management... and the 'Top selling Aussie favourite' (My description only...) is from more than one Chinese factory... which explains the lower price.
- This company does not supply the Top Selling Aussie Favourite.

I would forget the Hitachi,years ago before everything went to a lot of electronics they had some fantastic gear.Some of their bigger A/C equipment and chillers is still excellent.
But from what i have seen their smaller commercial and domestic gear,it is not the greatest.Lots of issues.

Your Daikin thoughts are the same as mine,and as i have said before,we fix/replace a lot of them.

I would have a good look at Mitsubishi Electric,we haven't had one warranty call in at least 5yrs.

IMHO,and FWIW,i wouldn't use anything else.

... I've been told that Mitsubishi units also tend to be on the quieter side than equivalent in Other Brands. (domestic splits etc)
I have'nt heard enough of them to be sure... - sorry, terrible pun.

Going out today to check out Bonaire replacement boxes (with their all-singing/all dancing AXIAL- flux, direct drive fan motors,) and YORK brand splits etc.

Term Deposit matures on Monday, so I've got another 2 days to stress / decide.!

But I like 'NO warranty claims' and 'quiet running' very much...

Originally Posted by superquag

According to the large DAIKIN re-seller I chatted with yesterday, their latest/better wall-splits are now using the more efficient hydrocarbon-based gas, the ducted ones still using R410. Efficient, but not quite as good as the HC...

Hmm, I'd take that with a grain of salt.

All efficiency means is that you can use a physically smaller compressor for the same capacity.
In commercial refrigeration we do this all the time, making a choice between using R134a or R404a.
The R404a units are physically smaller for the same capacity, but pull down times, etc. are identical if the systems are sized the same. (for all intents and purposes, as long as extreme ambients aren't encountered, then R134a wins out)


If you had a unit designed for R410 and then used R32 in it you might see a slight increase in capacity and ever so slight decrease in pull down time, but I'd wager the factories aren't doing that.

DAIKIN are built in Taiwan under Daikin management, Hitachi (cheaper than Daikin but still sold/supplied by this company, from Malaysia again under Jap. management... and the 'Top selling Aussie favourite' (My description only...) is from more than one Chinese factory... which explains the lower price.
- This company does not supply the Top Selling Aussie Favourite.

Daikin are made in Thailand.
As are Mitsubsihi Heavy Industries and Mitsubishi Electric, all in their own factories.
QC is excellent.

As you mentioned, Australia's favourite brand come out of the PRC, for what it's worth.

How do you find Panasonic Rick? I have had 3 inverters including a big double fan unit for about 4 years now and they have been fantastic. I also have a Kelvinator (large) and ot is very cold but often doesnt respond to the remote and requires being turned off at the external switch for 30 mins before i can supply power again and the remote then works again.

Cheers