Dehumidifier condensate water for batteries

[superheat6k]

Is the condense drain water pouring out of my dehum unit good enough to use as top up water for the batteries ? I know its not that much to buy the stuff, but I have litres of the stuff trickling straight into the sink with all this wet weather.

 

[Giblets]

Probably not because it will have all sorts of impurities in it which the batteries may not take kindly to.

 

[lynall]

Years ago we used to do just that on trucks, the place we got it from used to clean and wash air filters and then dry them, it was the water from the dryers we used, cant say it did any harm.

 

[Vara]

I have asked this question and the general consensus seemed to be that it would totally destroy my batterys within about 20 minutes the boat would sink and I would be forever damned, the reason given the impurities in the water.

I doubt that this is true but as I can source proper deionised water at €1.50 for 5l and I've sorted out my charging regime, so use very little of the stuff, I use my dehum water in the iron, for washing windows and the car, living in a hard water area it makes a real difference, no streaks or chalk deposits.

 

[JumbleDuck]

Probably not because it will have all sorts of impurities in it which the batteries may not take kindly to.

What sort of impurities?

 

[VicS]

Is the condense drain water pouring out of my dehum unit good enough to use as top up water for the batteries ? I know its not that much to buy the stuff, but I have litres of the stuff trickling straight into the sink with all this wet weather.

Its generally not recommended because of the risk of contamination.

I guess in a coastal location salt is a possible contaminate and that is not good for batteries.

OTOH some people get away with using tap water!

 

[2Tizwoz]

Shouldn't have much salt in it unless its already rotting the dehumidifier.

 

[Vara]

My mate who was a water analyst has retired so I can't get an authoritative test done.

My own primitive tests on dehumidifier water would indicate a pH of about 6 and a test on glass revealed no residue left after 500ml was left to evaporate.

In my own mind it is perfectly safe to use and if the price of deionised water rocketed I would use it.

Would love to see some detailed analysis, especially to differentiate between dessicant and refrigerant dehums.

Oh an afterthought, I also used it when I changed the antifreeze in my engine.

 

[rafiki_]

I bought 2.5l of de-ionised water from Asda a couple of weeks ago for £1.19. It really isn't worth using anything else at this price.

 

[maby]

I suspect that it might depend to some extent on the type of dehumidifier - there's no reason why refrigerant should produce anything other than distilled water - it is a distillation process. I'm not so sure about dessicant dehumidifiers - the water will have passed through the dessicant disk - though it is still evaporated and condensed afterwards. The tank in our Meaco dessicant dehumidifactor does seem to collect some yellow deposits and I'm not sure what they are - some sort of fungus seems most likely...