Dehumidifier water for coolant mix ?

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Mandrake
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Dehumidifier water for coolant mix ?

Post by Mandrake »

We recently picked up a dehumidifier and the amount of water it can generate is quite impressive, and it occurs to me that it is basically distilled water that should be ideal for the water part of a coolant mix ?

It's always annoyed me that in most cases your choices are to buy ready mixed coolant, or, gulp, use tap water as part of your mix...as distilled water isn't easy to come by.

Although I haven't used tap water in any of my Xantia's I confess to using tap water in coolant mixes in older cars over the years before that, (albeit in soft water areas) as ready mixed coolant wasn't readily available, nor was distilled water....

But now that I have the dehumidifier I'm thinking I should be saving the output of it in a nice large container so that I can start using concentrate to mix my own. Reading suggests that its not safe to drink because of the possibility of bacteria or viruses in the produced water, and also tiny quantities of metal from the evaporator and condenser can be dissolved in the water, however I'm sure that those quantities are tiny compared to dissolved metals in the coolant in the engine and it should be perfectly good to use ?

Assuming a 50/50 mix and 8 litres total coolant I only need about 4 litres - which the dehumidifier can easily produce in about a day... :)

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Stickyfinger
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Re: Dehumidifier water for coolant mix ?

Post by Stickyfinger »

Distilled water can be obtained in 5ltr containers from most auto factors/truck stop type garages, local to me its about £3.50.

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white exec
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Re: Dehumidifier water for coolant mix ?

Post by white exec »

I used to collect up to 3-4 litres in a day from an Ebac dehumidifier, while in the UK. Clean and 'distilled', the metal content is probably negligible, and nothing that a good coolant mix won't deal with. Simon is right: biggest problem is stopping it going 'bacterial' . . . something silver dropped into it would probably stop that. But then there's the cost of the silver... [-( Life is never simple.

De-ionised water (for irons etc) cheap as chips here in any supermarket.

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myglaren
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Re: Dehumidifier water for coolant mix ?

Post by myglaren »

The tap water here is remarkably soft and all I have ever used - with no problems arising.
I did used to buy deionised water from my local factor for the fork lift at work, £15 for 25 Litres.
They buy from a supplier of many of our bits and bobs now but pat far more for it.

I would be concerned that water from a dehumidifier or air con unit would have picked up dust and whatever else might be floating around from the air as they are open systems.

A mate of mine built a still quite cheaply. It was of necessity quite a good one as it wasn't water he was distilling - may be an option.

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Zelandeth
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Re: Dehumidifier water for coolant mix ?

Post by Zelandeth »

You'll find that the condensate collected by a dehumidifier is far from nice clean water. It contains all manner of bits of dust and such along with literally everything that it's condensed out of the air - not limited to but including any evaporated sweat from you and anyone else in the house, and anything from the dust and such that then dissolves in water.

Looking at the state the top of the condensate collection tray in the one air conditioner here and the dehumidier if it hasn't been cleaned every couple of months makes me sure that the water that appears in there is fit only for one place, and that's down the drain or for watering plants.

Distilled water is cheaply available from most decent motor factors and I wouldn't bother using anything else (unless you're in a soft water area where tap water is just fine - never used anything else when I was up in Aberdeenshire). Even with the cost of pre-mixed coolant to be honest given how long it stays in the car it really isn't that much of a problem is it? That's coming from the owner of a car with a cooling system that takes a little over 11 litres of coolant too!

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Stickyfinger
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Re: Dehumidifier water for coolant mix ?

Post by Stickyfinger »

Yeh.....all those 24volt batteries in the Sinclair to top up :)

wheeler
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Re: Dehumidifier water for coolant mix ?

Post by wheeler »

Never used anything but tap water either. Mind you it is super soft Scottish tap water. I even used to use the tap water for topping up batteries.

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Re: Dehumidifier water for coolant mix ?

Post by elma »

Have to confess I use tap water too. Mine measures as soft as it gets on the hardness scale. It's ill advised really tough as there are still a lot of other things besides water in tap water even if it is super soft.

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Mandrake
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Re: Dehumidifier water for coolant mix ?

Post by Mandrake »

Hence why I thought dehumidifier water would be a lot better than even soft tap water, and readily available for free...

BTW to the comment about dust - there is a fairly fine dust filter on the back of the dehumidifier and whilst the collection tank is not airtight it is a close fit to the housing of the main unit, so very little dust should get into the collected water.

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Re: Dehumidifier water for coolant mix ?

Post by elma »

I've heard of tumble drier water being used as well, possibly even on the forum at some point.

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Re: Dehumidifier water for coolant mix ?

Post by myglaren »

I'd be reluctant to use the water from mine - the condenser gets stuffed with crap (sorry, fibres) which is probably why it is subject to a recall.

If it were passed through a very fine filter then possibly.

Boiling tap water should precipitate most dissolved minerals but as said, I just chuck tap water in and have never had any problems.
Did look into buying a still but it looks too much like hard work, if I lived in an hard water area I'd just buy de-ionised water in bulk.

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Re: Dehumidifier water for coolant mix ?

Post by aneesh84 »

Based on what I have researched is that distilled water is extremely corrosive due to no salt dissolved and is definitely not recommended. Soft water is a much better option.

https://www.hyperlube.com/blog/blog/why ... ng-system/

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mickthemaverick
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Re: Dehumidifier water for coolant mix ?

Post by mickthemaverick »

I have lived in a very hard water area all my life and I have only used distilled water in batteries in the early days. Since they became sealed I don't use it at all. I have used tap water and bluecol or pink antifreeze according to the car and never had any sort of coolant system corrosion or gumming up. That is over 75 cars including some highly tuned machines!

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white exec
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Re: Dehumidifier water for coolant mix ?

Post by white exec »

The advice of most of the coolant manufacturers is to use de-ionised water, where dilution is required.
Ready-mix gets over the problem.

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Re: Dehumidifier water for coolant mix ?

Post by Gibbo2286 »

There is some confusion among motorists between distilled water and deionised water, most of the stuff sold now at the motor shops and factors is deionised not distilled.

Trading standards in Birmingham prosecuted suppliers for labelling deionised as distilled a long time ago.

Water from your dehumidifier is neither, it contains metallic particles, bugs and even the dreaded particulate stuff that your failing dpf gets clogged up with.