The King of Limbs

Radiohead’s new album, The King of Limbs, is out.

You can buy and download it (320kbps mp3) for £6 (about $9.95 AUD) here.

I like Radiohead.

Here is a picture:

Limbs

Pros and cons of ducted air conditioning

We’re loving our new central ducted air conditioning. (I was almost disappointed when the Sydney heat wave ended and we didn’t need it for a few days). Ducted air conditioning consists of a large outdoor unit (compressor) connected to a large unit inside your attic with ducts that supply the air to each room.

Pros

  • Powerful: Our unit is about the smallest available at 8.8 kw (meaning kilowatts of cooling power, not of electricity consumed), which covers our 3 small bedrooms easily on 40 degree days, and eventually cools our whole 100m2 3 bedroom house when it’s 35 degrees outside. For larger (or less shaded and insulated) houses, standard units go up to about 27kw (beyond that, I think you’d need to look at commercial AC).
  • Reliable: 5 year parts and labour warranties are standard and units are expected to last about 25 years. Split or window units generally won’t last as long, and more units means more moving parts, and often greater servicing and repair costs in the long run.
  • Unobtrusive: The ceiling ducts in each room are less noticeable and more attractive looking than the inside part of a split-system, window/wall, or portable air conditioner. This affects more than just aesthetics if your rooms don’t have a good spot for a split (Our bedrooms are quite small – about 4m x 3m with large windows – one of them would have needed a pretty complex installation, at significant extra cost). The outside unit (the compressor) is quite large (about 1.5m high and 1m wide) but a single unit cools the whole house, and you can put it around the side or back of your house.
  • Flexible: With at least 2 “zones” (we got 4, some installers will add extra zones cheaply) you can often cool just the rooms you’re using, to save energy and/or cool rooms down faster. I enjoy coming home on a 40+°C day, turning the AC on at full power, but only with the “bedrooms” zone open, so the bedrooms cool down to 25°C in about 15 minutes.
  • Quiet: The volume level ranges from “silent” to “noticeable” depending on the fan speed setting and how many zones are open (though the outdoor unit can be noisy if you are outdoors when it’s on)
  • Good technology: As ducted is expensive, ducted units tend to be good brand units with quality construction and recent technology. Most are reverse cycle (heating in winter as well as cooling in summer) and inverters (able to use less power when it’s not needed, so more efficient). Most dehumidify the air, some purify it too.
  •  

Cons

  • Expensive: prices start at about $5000 to purchase a small, cheaper (less established brand) unit and install in a single-story 2 bedroom house. We got a top-brand Fujitsu unit (with a free lawnmower) for $5800 (installed with 7 outlets and 4 zones). Larger (or less shaded/insulated) houses can easily cost 10 to 15 grand, sometimes more. A ducted system can also cost more (than equivalent-power high quality split systems) in electricity, but only if your roof space is hot (because the ducts aren’t perfectly insulated) or if you end up cooling more of the house than you would with splits (due to having too few / too large zones, or zones that include spaces you don’t always use at the same time). For larger units (about 18kw and above) you will need 3-phase power in your home. If you don’t already have it, that can add another $1500 or more to the cost.

Hope this helps someone. If you have anything to add, please let me know in the comments.

More Power! How much air-conditioning is enough?

I took a risk buying Fujitsu’s least powerful ducted air-conditioner. One installer flat-out refused to install it, saying it wasn’t powerful enough for our house.

Luckily it’s paid off: We’ve stayed cool during the days since it was installed, all of which have exceeded 40°C.

If you want to buy an AC, and would rather not gamble, read on. Here’s what I’ve learnt about selecting an air conditioner powerful enough to suit my needs and my home:

First: calculate your house’s “heat load”. List the rooms in your house. Include any space you want air conditioned (I included my hallway but not my bathroom, toilet, or laundry). Go to the FairAir.com.au size calculator and use it to work out how many kw (kilowatts) of cooling power each room needs, one room at a time. It will ask you about almost everything that effects the temperature of the room, including room size, window size and orientation, insulation, adjoining rooms, number of people in the room, etc. The results for my 3 bedroom house (100m2) were:

Room Fairair result (kw cooling)
Master bedroom 1.1
Kids bedroom 1.0
Study 2.1
Living room 2.7
Playroom 2.6
Kitchen 2.4
Hallway 0.5
Total 12.4
Bedrooms total 4.2
Rest of house total 8.7

But you’ll need to use the calculator yourself, as these will vary a lot based on what insulation you have, which way your windows face and their size, how much external shade (like trees or nearby houses) you have, etc.

Second: Decide what rooms should be cooled and how often. You may not need to cool the whole house at once. What rooms do you actually use when you’re at home? You’ll probably want the AC most on the hottest days, but how many of these days will there be in a year? For example, can your family just spend most of their time in just the living room on 40°C days? Unless your funds are unlimited, decide what you really need, versus what you want.

So far we’ve used our AC mostly in the bedrooms. As you can see above, fairair.com.au recommends 4.2kw for our bedrooms, so our 8.8kw has been adequate even in extreme 40+°C heat of the last few days. We had some guests over on one of those days, in the heat of the late afternoon, and it did take a long while (45 minutes or so) to cool the living room, playroom and kitchen areas (which need 8.7kw according to Fairair) but cool down it eventually did.

Third: Decide how much you can afford to spend. A larger unit will cost you more to purchase (and possibly in electrical costs, although apparently it can be cheaper to run a suitable unit at a moderate level than to strain an underpowered unit all day long). The next cheapest Fujitsu we looked at had 12.5kw cooling power for only $1000 more, which is a lot of extra cooling bang for your buck. It seemed like a sensible choice when already spending $5800 for the 8.8kw unit. But $5800 was already $1800 more than we’d planned to spend, so we decided to save the money, and are glad we did.

Some final thoughts: the numbers given to us by FairAir ended up being a pretty decent indication of how much power we’d need. If we ever want to cool the whole house down on a very hot day (like the stinkers we’ve had so far), our 8.8kw unit will definitely struggle to cool our 12.4kw house. But even in extreme heat, it cooled an 8.7kw area in less than an hour, and a 4.2kw area in about 15 minutes.

Booktopia free shipping code

As before, I have another free shipping code:

CHOICE

It expires this Monday 7th Feb 2011.

With Aussie prices and the US dollar as they are, though, don’t forget to check prices on Booko too.