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I’ve spent a bit of effort draughtproofing my house, which has been great for keeping the place warm. The downside is that a certain level of ventilation is necessary to prevent humidity building up. This means condensation, mould and other nastiness. This winter has been quite bad, with black mould growing on cold spots around the place. That’s unacceptable to me with wee kids in the house, so something needed to be done.

The problem has two solutions:

1. Get the humidity down by increasing ventilation
2. Eliminate cold spots where humid air would condense

The main sources of damp in a house will be the bathroom and kitchen. Using a cheap humidity monitor I’ve been tracking our humidity levels and found them consistently above the 70% danger level where problems arise. Clearly we needed to avoid pumping any more moisture into the house, so extract ventilation in the bathroom seems like the top priority.

I’ll be tackling the cold spots in due course too, but for now it’s time for some mechanical ventilation with heat recovery (MVHR).

What is MVHR?

I’m allergic to the idea of simply blowing air we’ve heated with fossil fuels straight out the side of the house, so instead of an extractor fan I went shopping for a through-wall mechanical ventilation heat recovery unit. Unlike a regular extractor fan these also draw in fresh air and pass it over a heat exchanger that recovers some of the heat from the outgoing air. As well as reducing draughts by supplying air to replace that extracted, it will reduce the cooling effect of sucking out the warm moist air.

Is it worth fitting MVHR?

New tightly sealed houses use whole-house MVHR systems, but these are a different kettle of fish. Indeed, fitting one is only worth it if your air tightness is very good. Given that I had a humidity problem I took my air tightness to be somewhat higher than it should be, and coupled to the carbon-saving and comfort boosting properties it seemed the extra expense was worth it.

The Vent-Axia HR25H

I chose the HR25H over several competing products (Envirovent Retrovent and it’s replacement the cringingly-named Heat Sava, Vent-Axia HR25 Solo and Tempra) due to the combination of good performance, low price, and generally positive reviews from owners. The unit is not balanced, it extracts slightly more than it inputs, but this is a plus point in my books as it will draw air from the rest of the house into the bathroom so that other rooms get the benefit too.

Essentially the HR25H is a plastic tube with a divider down the middle. This penetrates the wall, and the fans are mounted on the exterior end, with the filter and electronics on the inner end. A cartridge type plastic heat exchanger sits in the middle of the tube and the whole lot is powered by a switched-mode power supply unit located up to 5m away. Like all MVHR it’s designed to run constantly on trickle and speed up when needed. Like most people I opted for the humidistat controlled version so that it would automatically boost whenever it was needed. Sensitivity is controllable, although getting it right can take a bit of fiddling.

Installation

To install this MVHR you’ll need a 100mm or 152mm hole through your wall. I already had a large airbrick through the wall, which had been bodged about with during the time of previous owners and currently had a nasty plastic grille. This was a good thing, as core drilling all the way through 300mm of wall is not my idea of fun.

I had hoped to avoid drilling altogether, and simply bash enough of the airbrick out, but the vent narrowed inside the wall too much (difficult to see in the pics). You can hire core drilling kits for around £50, or hire someone else to do it for about £40-90.

It’s important to make sure you drill with a slight downwards slant (which is why the hole isn’t going through the top of the vent in the picture). Sitting a spirit level on the chuck of your drill and tilting until the bubble moves is good enough. This will ensure that any condensation that forms inside the heat exchanger drains outwards. This is important, you will get condensation inside it, and if it can’t escape it will fill up the heat exchanger and the unit will conk out.

I fitted a plastic wall sleeve to the hole and filled the rest of the void with expanding foam. I’m sure the latter is awful for the environment, but it’s supremely useful stuff for sealing weird shaped holes and penetrating little gaps. Then it’s simply a matter of sliding the HR25H into the sleeve where it seals very tightly due to the rubber seals around it. The kit includes 5m of cable to run to the power supply unit. I went straight up through the ceiling, across the top of the insulation in the roof and down to the wall outside the bathroom where an existing junction box was close. After wiring the MVHR to the low voltage side of the power supply box and having the mains connected to the high voltage side I hit the switch and it all powered up nicely. The power supply even includes a fuse and a switch, so there’s no requirement for any additional hardware to spur off your existing wiring.

Running

The unit is quiet in trickle mode. You can hear it nearby, but only if you listen for it. After all my hard work I needed a shower and was pleased when boost came on almost immediately.

Boost mode is much noisier, but so is any extractor fan. If I listen up the stairs I can hear it running in the bathroom if the door is open. If you shut the bathroom door it’s barely audible in the bedrooms adjacent to the bathroom, so I won’t be waking anybody up when I’ve got an early start.

Some action snaps:

Note the drop in temperature. Some of this is due to the accidentally high reading pre-shower, then the effect of running the hot shower, but some drop while ventilating is inevitable. External temperature was pretty chilly, probably no more than 10ºC. No heat exchanger is 100% efficient, and just think how much colder it would have got if we weren’t recovering some of the exhaust heat.

The humidistat is adjustable between 60-90% relative humidity. While the adjustment is just a case of twiddling a knob, you do have to remove the face of the MVHR to do this, which means it’s a screwdriver job. To be honest this is a pain , but once you get it right there should be no need to tinker. I found the best way was to set mine to be relatively insensitive so that it shut off too early. Then I tweaked it downwards until it went into boost again, and kept repeating this until I was happy with the RH level when it shut off.

Power usage is 2W in trickle and 22W in boost. I estimate mine will run in boost for about 2h a day, putting annual consumption at  under 16kWh (assuming it’s switched off for half the year). That’s around £2.25 for me, so worth every penny to prevent nasty mould spores getting at my kids.

Maintenance

Besides a regular clean of the filters little is required. Replacement heat exchangers are available and simple to fit. Some users have reported prematurely dead fans, but they have a five-year warranty on them, so it should only be nuisance value if they do conk out. The electronics are all easily accessible, and you can pull the whole unit out from inside, so there shouldn’t ever be any need to go up a ladder to attend to the outside.

Conclusions

I’m happy with the HR25H. At around £275 delivered it’s substantially cheaper than some of the competition, and performs well. My humidity readings are now in the low 60′s or high 50′s (max has been 67%), and it’s done so without wasting heat. Fitting it was pretty easy, especially since I could use an existing airbrick. Besides an occasional clean out it should do it’s thing without any effort from us, which is just how I like it.

“In every dual core phone there’s a PC trying to get out”

Or so reckons Canonical, who have been showing off their Ubuntu for Android system at Mobile World Congress. In a nutshell, a phone with Ubuntu for Android turns into a desktop PC when docked to a monitor and keyboard, and a mini media centre when docked to a TV.

It’s a pretty cool idea. There’s already starting to be quite a crossover between phones and tablets, and the latter have been eating into some of the laptop market too. The proliferation of desktop-type Android apps in the market suggest getting access to a full desktop environment when you dock your tablet would be pretty popular. I’m a bit more sceptical that even fast new quad core phones and tablets would be able to produce smooth HD video for a TV, so I think it’s best to take the media centre idea with a pinch of salt. I’ll believe it when I have an Ubuntu for Android machine in my hand and see it working.

You can’t buy a phone with Ubuntu for Android on it yet, you can’t install it like other Android apps and nobody has announced any dates. I think it’s definitely worth keeping an eye out for.  This could well be the next big step in the rise of the smartphone and tablet.

A new gadget landed in my kitchen over the festive season, an all-signing, all-dancing DAB/FM radio with network media playback and internet streaming functions, disguised as a Martian rugby ball.

Sounds like a mouthful, but it basically takes music or audio from anywhere and boshes it out. Available sources include:

• FM radio
• DAB radio
• UPNP/DLNA media servers on your network
• Internet radio stations
• Pure’s “The Lounge” content service

It comes with a touchscreen and a small RF remote. The latter is perfectly good for adjusting volume, but not much else. Actually switching sources and browsing is done on the screen, which is adequate, but often a little sluggish. TBH we’ve got used to better touchscreens in the last few years and this one isn’t quite up to par. Changing volume is particularly fiddly, and I haven’t even got fat fingers. Overall that’s a relatively minor inconvenience, and it’s not so bad you’ll be smashing it in rage.

Setup is very easy, it will find and connect to your wifi easily, and if you’ve already got a UPNP media server sloshing out music across your network connecting to it is straightforward. Likewise “The Lounge”, which provides a web interface you can log in to from any computer and subscribe to podcasts and the like. There’s also full access to all 6 bazillion internet radio stations, and a nice search tool to cut through them to find what you want.

Overall it’s very easy to hook up to a vast amount of content, which is exactly what we wanted for a device like this. But don’t fool yourself, this machine will not replace your main hifi. Sound quality is to be honest a little disappointing. It’s perfectly good enough for some tunes to cook or wash up to, but it has neither the volume nor the quality to do your favourites full justice.

On the plus side power usage is negligible, and the screen has a nice cheerful clock on it when you turn the radio off. There’s the obligatory nod towards “apps” but beyond some basic Twitter/Facebook/Picasa integration there’s not much going on in that department, and who actually wants to stare at their radio reading tweets anyway?

In general this gadget has the right idea, too many internet/radio mashups are missing critical parts of the picture. But the Pure Sensia does include the important bits: FM/DAB radio, internet streaming, network streaming, integrated speakers, and a decent sized touchscreen. Sure, some of those features need a bit of work, and if you want them ironed out your should probably wait for the new Sensia 200 to hit the market, but I’d still recommend the current Sensia as a massive upgrade from your current kitchen tranny.

Here comes winter again, time to crank up that central heating. But if you’re using an old-fashioned manual thermostat, you could be burning a lot of money for no good reason.

A programmable thermostat differs from a regular thermostat in that you can set it to provide different levels of heat at different times or on different days. They’re generally a straight swap for your old one, and cost about £50. Fitting it should just be a matter of unscrewing the old one from the wall, and switching the two wires that control your boiler to the new device.

Having fitted one of these beasties, you now have full control over exactly how warm you want the house and when. That means you can have it automatically warm up in time for getting out of bed or home from work, and cool down to save money (and polar bears) when you’re not in or asleep.

Will it save money and/or the planet?

Yes, if you tell it to.

For example, having it automatically lower the temperature by 5º overnight when you’re safely tucked up in your duvet can save you about £15 over the course of the winter. Which doesn’t sound like a lot, but it’s money for nothing, and it would save about 70kg of CO2 emissions (or about 200kg if you use grid electricity for heating). It’s also a lot cheaper than fitting a more efficient boiler.

If you’re at work Mon-Fri you could save even more. Setting it to frost protection only for 7 hours a day could save you £80 and 335kg of CO2 over the winter compared to leaving the heating at 18º. And that still leaves plenty of time for it to warm back up before you get home.

So you can see that even if you’re heating your home really comfortably, using a smart thermostat to avoid heating it when you don’t have to can pay for itself easily. Sure, you could achieve some of the same savings by manually turning your stat up and down, but having it done automatically is much easier.

Wifi comes in different speeds. The latest and fastest is 802.11n, or wifi-n. It’s pretty quick, but what if your Eee PC is an older model that only has wifi-g? Upgrading is actually really easy, and besides more speed should give you better range.

You’ll need a new wifi-n mini-PCI Express card, I used an Intel 4695 AGN because Intel are really widely supported. You can pick them up for tuppence on Ebay. You’ll also need a third antenna, which you can get here.

• Remove the battery and pop the bottom cover off your machine
• Disconnect the antennas, remove the two screws and remove the old wifi card.
• Route your new third antenna along the front edge of the inside of the case. The orientation of the antenna is important, and luckily there’s plenty of room for it if you run it under the RAM stick.
• Fit the new card and attach the antennas (the new one goes on post #3)
• Power up and enjoy.

I’m running Ubuntu, so it all worked as soon as I switched on. If you’re on Windows you might need to download some drivers from Intel and do the little Windows next > next > next > reboot dance. If you do have any problems booting try clearing the CMOS (remove the battery, remove the RAM and short out the two copper patches underneath it).

Sky broadband is a pretty attractive package if you already subscribe to their TV, but it does have one annoying snag. Sky insist that you connect using the router they provide, and enforce this by locking the box down with custom firmware that obscures your actual username and password. This means you can’t connect using any of your own hardware.

While this might sound great if you’re a Sky first line support monkey, it’s a pain for the customer.

Sky have used several different boxes over the years, and cracks for all of them have been published, which is a good enough reason to think twice about using the hardware they supply.

Get the tools:

If you have a Netgear or Sagem router: https://www.cm9.net/skypass/

If you have the new D-Link router: http://pathogenrush.blogspot.com/2010/10/dsl-2640s-password-extractor.html

Note that although the T&Cs say that the router Sky sends you does become your property, you should keep hold of it, as Sky are unlikely to provide tech support to you otherwise.

Having a baby is a pretty major change in your life, and things tend to get a bit hectic. I’ve found having a device in my pocket that can help smooth the way a bit really helps.

Just Noise

This app is like having a magic button on your phone that soothes grumpy babies. For some reason babies find white noise really relaxing. I’ve used this one to get my daughter off to sleep many, many times.

Remember the Milk

All of a sudden your life has just got a lot more complicated. Unfortunately this also coincides with a new adventure in sleep deprivation. Having an app that can organise you life and remind you to do things is invaluable. You can set recurring tasks, organise them by lists, tags, and a heap of other features. Requires a Remember the Milk Pro account, but the US$25 a year is well spent.

Aldiko

If you’re going to spend countless hours sitting up awake at night settling babies, you might as well do something useful with your time. Aldiko is a great ebook reader that actually makes reading on a small screen quite enjoyable. Plus it has a huge supply of free books ready to download. Mostly that means old book that are out of copyright, but if you can handle reading the Sherlock Holmes novels, War of the Worlds or some Sun Tzu then you’ll be fine.

One handed reading is a very useful thing to be able to do when you’ve got a bundle in the other arm. Another good option if you’ve got a Kindle is their Android app. It will even remember what page you were on when you switch back to the Kindle

Quick Alarm

Simple app, but does the job. Set yourself an alarm for a 20min catnap when you get the chance, and fight back against the sleep deprivation.

Baby ESP

Plotting and recording when your child eats, sleeps and poops may sound a bit anal, but it can also make your life a lot easier. Sometimes you don’t realise your baby has fallen into a routine until you track it, and then knowing when they’re going to do what ahead of time is a huge win. This is a paid app, but you get a fully functional seven day trial. And it’s only US$3 anyway.

At least that’s the result of a Nielsen survey in the US when they asked smartphone users how likely they were to stick with their current smartphone OS when they next upgraded.

Operating System	Would choose again
Blackberry	47%
Iphone	80%
Android	70%
Windows Mobile	34%

Another interesting stat was the OS which people said they would choose if they switched:

From this, we can take a bit of a potshot at estimating what the battlefield in the smart phone wars will look like in a year’s time. Assuming that everybody is able to defect to the system they’d most like to then to figures below show the Iphone snatching the top spot from the Blackberry. The problem with that assumption is that an awful lot of Blackberry users (and 40% of Iphone users, incidentally) are given their phones by their employer, so actually aren’t free to switch.

Operating System	Current US market share	Estimated share 2011
Blackberry	35%	23%
Iphone	28%	34%
Android	9%	19%
Windows Mobile	19%	15%

Personally, I don’t think the Blackberry number will drop as much, for the reason mentioned above. WinMo has been dying a slow death for a while, so a 4% drop doesn’t sound too unreasonable, despite also being popular with enterprise users. Recent polls have also shown Iphone uptake to be stagnating, while Android is surging. So my prediction is that my numbers for Android and WinMo will be accurate, but that the swing from Blackberry to Iphone may not be as severe as the numbers suggest.

Can Blackberry hold onto that top spot? Only time will tell…

I’ve blogged about FON recently, but didn’t go into too much technical detail. The magic box behind it all is the Fonera router.

The latest iteration is the Fonera 2.0n, which unsurprisingly uses the new 802.11n standard for higher speeds and better range wifi. That alone is probably worth the £79 pricetag, but this beastie actually has a lot more tricks up it’s sleeve. Features include:

• A seperate public wifi signal, giving the owner access to all FON hotspots worldwide.
• USB port for adding storage, printers, soundcards, etc. With storage added the router functions like a NAS. With a printer added it works as a print server. Or you can plug in a USB hub and do both.
• Transmission bit torrent client.
• Download tool for file sharing sites (eg: Rapidshare).
• Facebook, Picasa, Youtube and Flickr uploaders.
• Plug in a 3G dongle and it’ll create a wifi hotspot from it. So you don’t even need a landline or ADSL connection to use it.
• An open application framework for extending it’s capabilities.
• As a “self-tweeting router” it has it’s own Twitter account, and will tweet you when your up/downloads are done.

On top of this it has all the usual router functionality such as DDNS, QoS, static and dynamic IP addresses, etc.

Overall it’s an impressive and flexible device, and FON seem committed to keeping it an open platform and encouraging people to play about with it. Personally I wouldn’t hesitate to recommend it to someone looking for a simple cheap NAS and torrenting solution. It does have one major drawback though. Bizarrely, it doesn’t include a modem. You will need an ethernet ADSL modem or a modem/router as well. However, I was surprised to find how well it played with my old BT Voyager modem/router. It’s just a pain to have a second box plugged in just to get the Fonera online. For such a feature-packed device it’d be nice if it could handle the ADSL connection as well.

Despite this weird shortcoming, I think it’s a cool device. Access to thousands of wifi hotspots for a one-off payment is a good deal. Chuck in wifi-n and the bucketload of useful features and I can forgive it for not having a modem.

Incidentally, if it’s access to the FON network you want, they also do a stripped-back wifi-g device that’ll start you FONing for only £29, which is a great deal.

Why watch those downloads on your PC, when you can watch them from the comfort of the sofa?

The plan:

Watch video and photos and listen to mp3 music stored on our home network through the normal TV and stereo in the living room.

Issues:

1. Must have low power consumption
2. Must be quiet
3. Must boot fast
4. Must be stable and low-maintenance
5. Cheap is good!

What:

Mini-ITX based PC with a decent processor and onboard graphics, squeezed into a tiny wee case.

Why:

For a while now most of us have had two cool things in our homes: a home entertainment system and a network. But how can we get all our great digital content onto that nice big TV and hifi in the living room? The answer is a media centre PC.

How:

Hardware:

• Jetway JNC-62K Motherboard with onboard Nvidia 8200 graphics card
• AMD Athlon X2 e4850 high efficiency CPU
• Silverstone NT07-AM2 low-profile heatsink/fan.
• 1GB RAM
• 80GB SATA hard drive
• Terratec Aureon PCI sound card with S/PDIF
• Jou Jye NU-528i-B case with internal 73W power supply.
• Wireless keyboard with built-in trackpad
• TOSlink optical cable to get shiny digital sound to the hifi

Software:

• XBMC media centre software
• Ubuntu 64-bit, stripped down custom version. See Ubuntu Minimal: Build an ultra-lightweight custom OS

How much?

Grand total was £269 (+P&P), sourced from mini-ITX.com, Advance Technologies, and dabs.com.

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