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Makeit go Right
03-06-2009, 06:04 PM
Anyone know of a wall-mounted Room Unit that also pulls in fresh air? I thought the Daikin Urura did that, but maybe it is just a moisture thing -- not fresh air.

Duty wanted is 5kW nom.

(A cassette is a bit tricky for this application.)

eggs
03-06-2009, 07:21 PM
Hitachi did one a while ago, The Air Exchanger. It's not on their website now, but it might be worth giving them a ring to see if they have any left.

eggs

fromBG
03-06-2009, 07:45 PM
Daikin Ururu Sarara is the right choice!
Ururu Sarara's fresh air supply ventilation function is powerful enough to completely replace the air in a room*1 measuring approximately 26 m2 in two hours. It can quickly ventilate spaces like a living room, where the whole family gathers, by pumping in plenty of fresh air. You can use Ururu Sarara as a replacement for a conventional ventilation fan.

Makeit go Right
05-06-2009, 09:18 AM
Thanks. Yes, the Ururu seems to be the jobbie. Hitachi apparently gave up on their model a little while ago as not much demand for it. So it's a one-horse race here.
Thanks.

Abby Normal
05-06-2009, 12:01 PM
That is an interesting product, the air intake is in the outdoor unit, must be a fan powered intake that pumps the air in through a tube run with the line set.

Seems to force the fresh air through the filter and the indoor coil first. I like that.

Most of the PTAC units used in hotels in the US south, will only draw in the fresh air right to the supply fan, bypassing the coil and mixing with conditioned air.

icecube51
05-06-2009, 04:10 PM
some italiën brands have this system to. there is a fan on the outside unit who leads fress air throu a plastic flexible connected to the indoor unit and blow the fress air over the evap and filter.
i think the brand is cald "Artel ", they have a few models like that.

Ice

sinewave
06-06-2009, 06:28 PM
Clickety Click! :)

http://www.daikin.com/global_ac/products/residential/urusara_series/videos.html

Makeit go Right
07-06-2009, 02:31 AM
Great vid, Sinewave.

The ventilation rate of this equipment is not so easy to find. Noticeably, the kit is promoted as a "humidifying-dehumidifying" system, rather than a fresh air system.....in Japanese, Ururu =humidify and Sarara =dehumidify (maybe I have that the wrong way around).

Anyway, I finally found the numbers: 32m3/h, which is just under 9 litres/sec (before you go extending the air-hose beyond 6m). So, for commercial (offices etc) it’s barely okay for a one-person office (no visitors) but not much use when there are more people in the room.

Shame that the vent line can’t be rigged to push more air through to the Room Unit, say 2x or 3x. Then it would be more useful.

Magoo
07-06-2009, 03:12 AM
I am thinking that most manufacturers would not promote fresh air introduction as a standard feature. Due to the fact that would derate the equipment efficiency rating. That star sticker thing on each system.

Air Change
12-06-2009, 02:57 AM
The Daikin unit doesn't provide a very high flow of fresh air, not sure of the standard in the UK but in Australia it's 7.5 l/s if filtered.

You could use a high wall split for the cooling/heating and a wall mounted heat recovery ventilator such as the one our company makes to provide the required ventilation, I'm sure a UK supplier would have a similar product.

airchange.com.au/Products/ERVWallMount/tabid/74/Default.aspx

Abby Normal
18-06-2009, 12:33 AM
Sometimes there are residential procedures to figure out how much fresh air a home would need.

Then a lot of the time, this fresh air volume gets added to the return duct side of central forced air cooling and heating systems.

Now when you look at the house as a whole the amount of fresh air seems like a lot, but when you think about how much fresh air goes to each room, it can be very mickey mouse.

If you live in a reasonably tight building and you are not in the habit of opening your bedroom windows, you would probably be surprised at how high the CO2 builds up in there, and this is not even considering when 'your mrs' obliges you and your metalobolism is sped up.

So with multiple fan coils serving mulitple rooms, I do not think the small amount of air these things provide is all that bad when you look at the big picture.