I'm getting a price from Pow Science Toys - who are happy to ship internationally via USPS. Will let you know when I get something. They also do the "pro" kit.

How about one of these, not that I have any interest in model railways, tropical fish or stamp collecting.
http://compare.ebay.co.uk/like/170779628800?var=lv<yp=AllFixedPriceItemTypes&var=sbar

Try this:

Edit: Tish, doesn't seem to want to play.

A model railway smoke generator would probably do the job. Usually around £20 plus the cost of the oil. Pretty much any decent model shop should stock them, and they could be wired up to run from a battery easily enough.

[EDITED: cross posted with ST's description of exactly the thing]

I'm not sure about the ultrasonic mister unit, but they are so cheap that you might want a go at a DIY version. The misters are less than £3 inc delivery (http://www.ebay.co.uk/itm/Mist-Maker-Fogger-Mister-Humidifier-Pond-Water-Fountain-/270983779527?pt=UK_HomeGarden_Garden_PondsWaterFeatures_UK&hash=item3f17e454c7) , and could just be plonked in a small cup of water and wired to a suitable power supply.

''... for smoke, try these:

http://www.screwfix.com/p/smoke-pellets-5g-pack-of-10/64647

Cheapest 'smoke generator' I have found!

Cheers... ''

Agree, but generally too much smoke!! You need to be able to control a smaller amount.

<blockquote><cite>Posted By: djh</cite>
The ones I saw in Harrods last weekend cost a darn sight more than £3</blockquote>

Makes you wonder about the mark up on them, doesn't it, when you can buy them direct from China, inc postage, for such a low price?

Yes, I recommend them (with necessary caveats re not burning down your house based on my 'advice'!), though even a whiff is enough to set off some people with asthma.

I don't recommend these to anyone
http://www.smokescenenyc.com/Marlboro.html
If you ever see any, send then to me for disposal

Posted By: djhNick Grant made an excellent post about this topic last year:
http://www.aecb.net/forum/index.php/topic,3040.0.html" rel="nofollow" >http://www.aecb.net/forum/index.php/topic,3040.0.html

He mentions a hot wire anemometer costing £100 but the cheapest I can find online so far is £185 delivered.

Anyone got a link to a cheaper one?

> hot wire anemometer costing £100 but the cheapest I can find online so far is £185 delivered.
> Anyone got a link to a cheaper one?

Not exactly a product you can buy, but info to roll your own.
There was an article in this months edition of Elektor.
I have the paper copy but you can get an overview here:-

http://www.elektor.com/magazines/2012/june/dual-hot-wire-anemometer.2159380.lynkx

Oh, and I just found this:-

http://www.coleparmer.co.uk/Product/Testo_Velocity_Stick_Thermal_Anemometer/WZ-37466-00

BTW, hey RobL, you did see Steamy Tea's homebrew MVHR I presume? I don't see any mention of it in this thread.

Hi Sprocket
The CO2 meter that I have, which I recommend, is still available from ebay - it's this one (£74.9+£9.5 P&P):
http://www.ebay.co.uk/itm/Desktop-Indoor-Air-Quality-Monitor-Temperature-RH-CO2-/230803689663?pt=UK_Sound_Vision_Other&hash=item35bcf8d0bf

I think the sensor is a special colour led, light being absorbed by CO2 - or something like that. But TBH I haven't looked into it. It switches on and just works - no appreciable warm up, so far as I can tell accurate (well it gets outdoors about right!). Doesn't get hot, PSU that came with it is rated 5v 600mA and runs cool too.

Yes I've seen ST's homebrew MVHR - he's partly inspired me to work on a homebrew waste water heat exchanger project. I'll post up on it sometime!

Like that people get a kick from reading my exploits! Mrs Robl is very understanding :-)

Sprocket wrote: "Oh, and I just found this:-
http://www.coleparmer.co.uk/Product/Testo_Velocity_Stick_Thermal_Anemometer/WZ-37466-00 "

Good find!

I see they also have a fog generator:
http://www.coleparmer.co.uk/Product/FlowMarker_Fog_Generator/WZ-10322-30
It's only £3,436!

Posted By: RobL

> The CO2 meter that I have, which I recommend, is still available from ebay - it's this one (£74.9+£9.5 P&P):

> I think the sensor is a special colour led, light being absorbed by CO2

Yes, this is the non-dispersive-infra-red type sensor - the LED version of which are the best type (the older versions use an incandescent bulb - which take a while to warm up and stabilise, plus also the incandescent bulb ages and blackens).

I looked into these a while ago for an HVAC controller design - there's a company near Glasgow which makes some quite nice sensors (e.g. small size LED-NDIR sensors, with integrated temp+humidity, and serial output), but their small order quantity prices were pretty silly >£100.

BTW, for another £15, the same ebay seller which you found does a different model with a relay for CO2 set-point control (e.g. to turn an HRV on), and which also has an RS232 interface:

http://www.ebay.co.uk/itm/330748222997

... not so pretty as the nice round one tho'

I'm edging slowly towards the point where I will want to do some DIY leak testing before getting a proper blower door test done. I reckon it is worthwhile to do that and have the comfort of a day or two of checking for leaks rather than running around like a mad thing on the morning of the blower door test.

So what I am interested in is to de-pressurise the house to a reasonable level so that I can check for leaks rather than try to estimate the actual air tightness of the house.

Having read the link that RobL posted http://www.nlcpr.com/Pressuretesting.php I am looking at using a cheap 240v fan like this one from RS http://uk.rs-online.com/web/p/cooling-fans/7001439/?origin=PSF_345653|fp

I'm attracted by the fact that it has a full cowl for safety something that you don't get with the car fans.

It's rated for 5100 m³/h so it should be up to the job. But is it a big drawback that it doesn't have an outer rim around the fan tips?

I guess that this "220v Booster Fan Electronic Speed Motor Controller" from ebay should make it possible to fully control the fan speed? http://tinyurl.com/cvdblmg

And this manometer can give me the pressure differential? http://tinyurl.com/bqmyxq8

I probably don't need the speed controller if I am not trying to work out the actual air tightness figure but I guess as it's cheap it's no harm to have it and it would be quite nice to work out the air tightness on a DIY basis and see how it stacks up against the proper blower door test.

So before I go throwing out money on the wrong things would someone more knowledgeable be kind enough to verify I am getting the right stuff or if not suggest alternatives?

Thanks

Chrispy.

Thanks Rob, I forgot to mention that I have already got a hot wire anemometer for measuring the airflow so that is covered.

Looking at the car fan it doesn't seem to shift much air compared to the 220v one, 1130 m³/h vs. 5100 m³/h?