Dehumidifier for distilled water

koraks

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It's not meaningless and it's only argumentative in the sense that you happen to not like some of the answers you got. That's what happens sometimes if you ask a bunch of people. Some answers you like, some you don't.
 

snusmumriken

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Actually the info from @koraks changed my ideas. Coincidentally, I’d only just started to collect the water from our dehumidifier for darkroom use - always used filtered tap water for everything except the final wash in shop-bought deionised. I won’t discard the 15 litres of home-made stuff until I see a reason to, but I will be studying it very carefully over the coming weeks! And I don’t think I will be collecting it again: it’s just not worth the risk.
 

Ian Grant

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Koraks is right. Water from Dehumidifiers or air conditioning is not safe for photographic use. If filter and boiled maybe, but that adds costs. It will contain high levels of biological contaminants.

Ron Mowrey/PE warned about using condensed water some years ago. It might look clean, but it is dangerous to drink, because of the microorganisms it contains and these will multiply. You don't want high levels absorbed in to emulsion or paper bases.

Ian
 

drew tanner

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I’m not going down this path myself, but for the sake of discussion, would running the dehumidifier condensate water through a charcoal filter, like a Brita, remove the contaminants of concern?

Locally, I get a three-pack of gallon jugs of distilled water at Giant Eagle for $2.99. Cheaper by 20-40 cents per gallon compared to elsewhere.
 

Ian Grant

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The Brita filter cartridges use de-ionising resins (not charcoal) and are designed to remove the mineral content from tap water. Thy won't remove the microbial content from contaminated water. I have to use a Brita or similar filter jug in my kitchen as my tap water is very hard, coming from sandstone boreholes.

Here in the UK/Europe distilled water is much more expensive than the US. I use a second (actually Brita) filter jug in my darkroom for mixing developer concentrates etc from raw chemicals. I dilute for use with tap water.

Ian
 
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RalphLambrecht

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agreed, I'll use it with caution and certainly not drink it. Biological contaminants are a real concern. Unfortunately, I'm not set up to prepare a culture. Otherwise, I would test for that, too. Maybe I can convince my doctor to do one for me.
 

Dustin McAmera

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I have a dehumidifier, from when my house had a (worse-than-now) damp problem; but I don't use it now. I wondered if there was a better thing to do with the produced water than putting it down the sink. Even just the packaging puts me off using bought distilled or deionised water in any large quantity.

I think if you have significant microbial life in the collection tank, you could reduce that a lot simply by washing the tank out after emptying it, and emptying frequently even if it fills slowly. I think the device I have lets you remove the tank, and trail a pipe out to flow directly into the drain; that would let you choose your own container - something more easily kept clean.

You could also add something to inhibit growth; you can get camping water filters with particulate silver in to inhibit bacteria, and copper bottoms inhibit shellfish on boats. So maybe try putting a short piece of silver or copper wire in the tank. OTOH, distilled water is likely to take up a small concentration of the metal (I guess if it didn't it wouldn't work). In the lab I used to work in, one of the benches had tap water from a softened water supply, running in new copper pipes, and on a Monday morning that water would run faintly blue for a few minutes.

If there are significant particulates, try running the water through a coffee filter before using it.

If I didn't live in a grimy city, I'd also look at my rain water as an alternative.
 

DREW WILEY

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For effective filtration you'd need scientific grade funnel filters, especially if you want to remove water mold spores. These kinds of filters aren't terribly expensive, but cost more than coffee filters. And being very fine, they're somewhat slow.

In terms of air intake to a dehumidifier, you'd need multiple-stage micro fine air filtration. That doesn't come cheap. I use that on all my air compressor lines in the lab; but everything in between needs to be flushed out and sanitized too. You'd be shocked how many dental offices have skanky unclean water lines at their stations. Microbes built up quickly.
 
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FotoD

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I use the water from my dryer for non-critical things. It works great after going through a coffee filter. The water can sit in a bottle for months and I've never had anything grow in it. However, it smells a little like detergent. I don't mix stock solutions with it and I don't use it on film.
 

DREW WILEY

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Do you stomp wine grapes with your feet, after walking through the cattle pasture barefoot? People did for centuries. Maybe that's what gives older vintage its special whatever.
 

Kino

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My dehumidifier coils are made of aluminum; no thanks!

However, I do tend to empty the reservoir into the clothes washing machine to reclaim the water. It only makes up a small fraction of a full load, so it gets to do double duty on the way out the door...
 

BobUK

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I bought a new dehumidifier last winter and contemplated using the condensed water for photography.
After about a fortnight the plastic collecting chamber was becoming stained enough to put me off the idea. The water looked clear in a glass beaker, but I had my doubts about the water purity. Something is causing the stains, but I have no idea what.
It just goes down the drain now for peace of mind's sake.
 

deemdoubleu

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My dehumidifier tends to build up with mould and I add a bit of bleach after emptying to help keep it clean. Personally, I've had really good results using de-ionised water. It doesn't leave any residue on the film which I noticed when using ordinary tap water (even though we live in a fairly soft water area and don't have problems with build up of limescale in kettles etc.).
 

Don_ih

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Just use tap water and stop worrying about it. Dump the water from the dehumidifier tank and forget about it. It's all pointless screwing around for no good reason.
 

UnderwoodPhoto

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I have an enclosed polebarn (conrete floor) for overflow storage with a large dehumidifier sitting on a clear plastic 55 gallon drum. The drain hose fitted to the drum and a submersible pump inside the barrel to fill 5 gallon carboys. It will fill 3 times per year. I use the water (condensate) for mixing my minilab chemistry and b&w dev and fix. No issues, mold or dust over the past 18 years.
 

DREW WILEY

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My own tapwater is excellent. It's basically snowmelt brought all the way across the State through aqueducts, and needs only mild treatment. I use it for everything except final film rinse. But heck, there are certain adjacent counties that rely on small local reservoirs, or else on River water, with so much chlorine added that I can hardly tolerate taking a shower in that, let alone drink it.
"Tap water" therefore has various connotations, depending where you live. And in arid rural areas, where wells are often used, the mineral content of their "hard water" can be a real issue.
 

kozesluk

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just a side note here - you can get an RO system for aquariums (they are the simplest collection of components to make RO work - carbon pre-filter and then membrane) with very low production performance (about 50 GPD) for about $50-100. it will produce very clean and extremely soft water (easily under 20ppm so on par with most store-bought options) for very cheap. some of them even run on tap water pressure so no electricity cost.
 
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RalphLambrecht

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thanks for the info.
 
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