Wednesday, September 12, 2012

Japanese Air-Con Guide #2: Window Units (窓用エアコン) and Installation

It's been 36 degrees outside for long enough to give in and buy an エアコン (air-con) unit. But what's the best deal? They seem to range in price from 30,000 to 120,000 yen. The cheapest air-con unit in Japan, if you don't have the apparatus already set up for a wall-mounted unit, is a portable window conditioner. Full details below:
Many modern Japanese apartments already have air-con. If not, they often have at least the ventilation hole, and perhaps the hanging studs, too.

However, if not, then what to do? You can buy a wall-mounted air-con starting reasonably cheaply (35,000 yen or so), but then you'll need to have it fitted, which could set you back another 10-20,000.

Alternatively, you can buy a portable, window-mounted unit, or 窓用エアコン (madoyou eakon).

For approximately the same price, you can get something like this:

It will sit in your window frame, bordered by a fitting to keep it snug against the borders, and do the same job as a regular AC. And best of all, installation is easy enough to do yourself.

Here's a quick how-to for installation. Be aware that each unit is different, and you'll have to examine the instructions for your specific one, but they all share some common elements; so use this guide as a vague outline.

1. You'll need a window unit to fit your specific sized window. Some only fit up to 170cm, some even less. So first step: measure your frame.

Bracket with screw fitting to the left
Bottom screw fitting

2. Frames usually screw onto the metal surround of your window, but this depends on the available milimetres of frame. For example, my frame only has a lip of about 1mm. Screw-on units need about 10mm to hold securely. Luckily, mine is a common problem and units usually, if not always, come with metal brackets to screw on in lieu of the frame.

Frames stretch to fit
3. Once the bracket is in place, you can fit the aircon frame. This will sit in the window frame more or less precisely, and be pressed against the open window to form a seal (it will actually have a seal attached, which you will need to trim to fit the top and bottom). The frame will stretch to fit.

4. A stopper is used to keep the open window firmly shut. This may need to be screwed into your aluminium window surrounds for added security.

As if by magic: daytime
5. Then the aircon fits into the frame. Any discharge will dribble out the back, so if it doesnt come with a hose you might want to put something under it to catch the water.

Sounds simple? It is! Shouldn't take more than half an hour to set up the first time, then less next time if you move or take it out for the winter.

Where can you buy a window-mounted unit? I'm glad you asked. Many big home centres, like Grand Stage or Cainz will have them. But I recommend Amazon. Prices are generally better. Rakuten is also worth a look.

Refer to last week's post for a description of the features to look out for.


  1. Thanks for that great info. I been looking at these but the guy at Yamada Denki tells me they are useless for a 8 tatami room, I am off the mind that if it is built to operate in a 4 tatami room then it will work in a 8 tatami room with reduced efficiancy - what is your opinion on this? Thanks

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