ok… funny question was presented to me last night, and i really had NO IDEA!!!
“can’t i use the water from my dehumidifier as top off/make up water?” i guess my initial thought was no, and i told the guy i really wasnt sure, and so i would not use it until i knew for sure. are airbornes (i.e. air freshener, cleaner, etc.) in the water from the dehumidifier? or i guess technically, ONLY H2O boils and then collects in steam/condensate… right? so does the same process apply here???
Well considering that the plumbing in a dehumidifier is generally copper I probably would not use it for that reason alone.
But airbornes that are being removed attached to the water molecules in the air would also be present and could end up concentrated enough to cause major problems.
I will be tagging along to hear what Shawn, Ken, and Ian have to say on this topic though.
Craig is correct in part because a dehumidifier does not evaporate water but condensates using a cold coil to lower the temp so that the air can not hold as much water. So any pollutants will be concentrated. This is the same principal with storms and the dew point. At a certain temp air can hold different amounts of water. Lower the temp and the excess water condensates (rains). The rain removes pollutants sort of a washes the air as it drops to the ground. Dirt sticks to the outside of the water droplet. Good Link explaining dehumidifiers
[quote=“fishguy9, post:1, topic:2416”]
ok… funny question was presented to me last night, and i really had NO IDEA!!!
“can’t i use the water from my dehumidifier as top off/make up water?” i guess my initial thought was no, and i told the guy i really wasnt sure, and so i would not use it until i knew for sure. are airbornes (i.e. air freshener, cleaner, etc.) in the water from the dehumidifier? or i guess technically, ONLY H2O boils and then collects in steam/condensate… right? so does the same process apply here???
somebody help me out here… lol[/quote]
Guess technically you could but the water that comes out of mine always has a funny smell so I don’t use it in my display tank for top off but have used it in a quarentine tank for top off and didn’t hurt anything in there.
The coils in the dehumidifier are cold and the chill the air and water condensates (turns to water droplets) There is no evaporation in a dehumidifier. Yes only water evaporates but since there is no evaporation the water is still holding all the gunk that was in the air. (pollen, mold, dander, etc…)
Rain falls for miles and collects dirt and debris that is suspended in the air. In a humidifier, I don’t think that would be the case. Of course, the air in your house is way more polluted than outside air a lot of the time. Maybe if you incased your humidifier in an air filter. The carbon coils are still an issue though.
Can anyone test the water from a humidifier that uses a portable TDS meter?
the evaporated water will not have a TDS content. the solids will be left behind. there is a lot of survival gear that uses this principal to make contaminated water potable. we used something similar during survival training in the marine corps. we boiled not so clean water, collected the evaporated portion to drink and it was fine.
the problem with dehumidifiers, like many have hinted at, is the contamination from the air. there is a fan on dehumidifiers that not only pull in the air, but everythign in the air. thats why they have filters which get VERY nasty VERY quickly IME. its not the water you have to worry about, but all of the nasty stuff sucked in from the air.
if you had a sterile enviornment, and you evaporated tap water and condensed the vapor in a process that was free of airborne contaminates, then yes, you could use it just fine. im not sure about the DI component, but it would read 0 TDS and would likely work fine for our aquariums.
[quote=“a1amap, post:9, topic:2416”]
Craig you have a dehumidifier; Do you have a TDS meter? If not I have one you can use.[/quote]
I can’t find my TDS meter, but I will gladly borrow yours to run a quick test.
[quote=“logans_daddy, post:10, topic:2416”]
this seems fairly straightforward to me.
the evaporated water will not have a TDS content.[/quote]
But therein lies the problem with this logic. Evaporating water will not have TDS - water from a dehumidifier is not evaporated to steam and then collected, it is cooled to below dew point and condenses from the air, therefore any pollutants (i suspect) would still be present.
But therein lies the problem with this logic. Evaporating water will not have TDS - water from a dehumidifier is not evaporated to steam and then collected, it is cooled to below dew point and condenses from the air, therefore any pollutants (i suspect) would still be present.
ok, it might just be me(and it often is) but i dont follow this at all.
that fact that water is evaporated is the very definition of turning it from a liquid into a vapor. the dehumidifier doesnt have water going into, it has humid air(which i contend doesnt contain TDS). the condensing process simply takes the water vapor from the air and condenses back into a liquid form minus the contaminates which is left behind. i could be wrong, but this was alwasy my understanding of the process.
the fact that TDS doesnt evaporate is the WHOLE point of using RODI. If it evaporated with the water, our systems would never build up toxix levels of heavy metals etc. the whole process is apparent with salt creep. salt creep is the “TDS” left behind when water evaporates. and yes, our saltmix is TDS for those keeping track:)
Will check my TDS on my dehumidifier tonight just for __its and giggles. I would never ever use mine in ANY tank though. I have had three dehumidifiers in the past and all of them have had nasty smelly buckets. I have had to clean them out several times, but get dirty quickly. I wouldn’t use it.
Damn it. I stuck my TDS in the dirty water just for the heck of it went to turn it on and it was already on and out of batteries! I have two of those batteries, but not the 4 it takes. Errrr.
Stand by my previous post currently. Dealt with a lot of purified stagnant water in the past and never had anything look like my dehumidifier bucket. And it gets 0 light!
Lets forget about evaporated water, evaporation and the like and just ASSUME (we know what that means…) that there is water in the air, lets not worry about how it got there.
Ok, so there is water in the air, and we know water can hold all kinds of ‘stuff’ (isn’t that why we do these TDS meters?), so why can’t the water in the air hold this same ‘stuff’. ‘Stuff’ is pollutants, acids, bases, ect. I think someone mentioned it already but think acid rain. The dehumidifier is basically making rain in a bin, and whatever is in the water in the air, is now in your bucket.
I think some of you guys may be thinking somewhat of a ‘still’. A still works by boiling off a substance from another and then condensing out the boiled off substance. In this case you have both evaporation and condensation and should end up with fairly pure end product provided their boiling points are far enough away.
So my thought is that yes dehumidified air has got some sort of ‘stuff’ in it. How much? Depends on your indoor air quality and what is in your indoor air. I would assume that some of the ‘stuff’ is too large to go into solution when the water is in the air (humidity) but can go into solution when it is pooled.
Take a look at your dehumidifier bucket. See any build up of ‘stuff’ on the bucket?
ok. here is my question, and if i knew the answer i wouldnt ask! ;D what is the difference between boiling water and condensing the water vapor and condensing evaporated tank water besides the air quality which i already brought up? if there is a distinction between the two? if so, i dont follow. personally, i dont think the “yucky” stuff in the dehumidifer comes from the water at all, but rather the air! this is obvious by looking at the air filters and just how nasty they get. acid rain isnt a good analogy for this IMO. the point of the discussion is wether or not the water will leave behind TDS when evaporated, not if it will recombine with other stuff as vapor which i think is two seperate things. i think that evaporated water will leave behind the solids that give it a TDS reading and if collected in a sterial way should have 0 TDS. however, just like with acid rain, if the water is mixed with other contaminents after it it is vaporized then of course there could be TDS content after its condensed.
I’m trying to follow your post but I ran into the next line and got lost, but after reading it a few times I think I got it.
The point of the discussion I gathered was, is dehumidifier water safe to use for top-off. Let’s not confuse evaporation with the dehumidifier, as its condensation happening there, not evaporation.
If its will evaporated water leave behind TDS, then yes, evaporated water will be pure. If you could contain it and condense it, it could be re-used, but it’s not contained.
I’m guessing what you are getting at is the water the dehumidifier makes is from the evaporated tank water? Sure some of it is, but it is also from everywhere else in our lovely humid Delaware, and it is not contained, as in it has time to contact the air and gather up the ‘stuff’.
So no, I don’t see a distinction between the two, except for air quality which you did mention.
So if you put a dehumidifier directly over your tank you can collect up the evaporated water and dump it right back in. After it passes over those copper pipes.
After it passes over those copper pipes.