Distilled / Purified Water for RCM...again!

I haven't used it, but there's no need to shove it anywhere it would seem.

http://www.endlesswaters.com/d...ed-or-purified-water

It should be fine Tony.

The posterior sounds good to me.

Mista h

Thanks for reaffirming my faith in mankind. Looks like I won't be needing these then.

The OP's picture doesn't load for me, and I'm going to steer clear of Vaseline/rubber glove gags, so forgive me if I'm missing a point somewhere.

The best source of distilled water that I know of is a dehumidifier. I prefer lower levels of humidity in the home, especially in the UK where it's often so humid outside that the humidity comes down in lumps. The fringe benefit is that the water collected has been effectively distilled out of the atmosphere so, whilst you can just chuck it down the sink, it works a treat in irons, windscreen washer pots and (I daresay, though haven't tried myself) RCMs. At my last school, the tapwater was so hard that the Chemistry Department asked us to collect the water from our dehumidifiers in Physics so they could use it in experiments rather than running their still all the time and having to descale it every couple of weeks. When they tested what we were producing for them, it measured purer than the output of the still.

If you go down this road, make sure your dehumidifier has a compressor in it - some newer ones (e.g. DeLonghi) seem to use some sort of dessicant and I haven't tested the water output of these to see how it behaves. It may well be just as good, of course.

Mark

Delonghi humidifiers aren't all they appear. I bought a Delonghi DES12 thinking it was a desiccant machine. I wanted desiccant machine because they are quieter. Unfortunately, the DES12 doesn't use a DESiccant it uses a compressor.

I complained to John Lewis, but they didn't want to know. They even removed my feedback where I stated it was not Desiccant but compressor.

GO FIGURE.

Although, I must say it's a good machine, if a bit loud.

Mark,

Intesting comments. Cost wise, I paid £3.49 for those 5 litres of purified water that will last a little more than  6 months. The setting of a dehumidifier on the other hand would not be so cost effective.

As for the vaseline/rubber gloves... very cost effective and multiple use to say the least!

Best

Tony

Distilled water is collected condensed steam from boiling water. The steam is very pure as all the impurities are left behind in the boiler as scale. This may be expensive as the energy required to produce it will be quite high

Purified/deionised water has the impurities removed by a chemical exchange process. The quality of this water can vary depending on the process.

The Genteel Purified water above has quite high conductivity (5uS/cm)for purified water, but should be ok for RCM's.

I wouldn't be too keen on de-humidifier condensate. The condensate may not always be polished and will contain impurities.

I fortunately have access to deionised water with a conductivity of 0.05uS/cm. 100 times purer than the Genteel water. Our water treatment plant can produce on average 200 metric tonnes/hour 24 hours a day. The cost to produce this quality of water is 20p/metric tonne. The water is free as it is abstracted from a borehole under licence, the 20p is the chemical cost for regenerating the process.

The odd litre or two for record cleaning is not missed

I think you misunderstand me, Tony. I wasn't suggesting that it would be cost-effective to buy a dehumidifier solely for the purpose of making the odd litre or two of distilled water - that would be crazy. I was simply saying that if one was thinking of buying one anyway for other reasons (perhaps one's holiday home in the Somerset levels might unfortunately be in need of one, for example), then a fringe benefit (my words) would be that the water it collects is, in many ways including measureable ones, equal to distilled water produced by more conventional means.

As you mentioned numbers though, for comparison my dehumidifier can produce about 2 litres in 12 hours running at 550W which works out at about 33p per litre (assuming cost of 10p per kWh). This is just under half what you paid for yours, which is sounds about right when distribution & retailer costs are factored in.

Iron Cobra: when the Chemists asked us if they could test the dehumidifier water I too was sceptical about just how good it would be. I simply report their findings, which was that its conductivity was better than that produced by their 'proper' still and they used it for many years in school Chemistry experiments without noticing the difference. Since we were running the dehumidifiers anyway, it made much more financial sense for the school to use the still less, if at all.

Mark