I want to make a thing on the roof that lets the sun heat collected rainwater and then feed it into my hot-water heater. For this first device, I'm just playing around to see if I'm really motivated so my only real concern is water safety, not efficiency. I guess any pre-heating at all is better than none and I'm sure rainwater is way healthier than city water or leeching plastic containers. I've been thinking about materials, galvanic corrosion, etc. I read somewhere about using the heat exchanger from a central heating unit but I don't know where to get one for free. I can get an old car radiators tho, and I think being flat and lightweight is good considering I'm gonna also be collecting rainwater and will need surface area anyway. I need some replies about what specific materials automobile radiators are composed of and whether they are safe. I can imagine they consider corrosion and leeching causing problems inside engines when they select materials for car radiators. Is it possible that contaminant levels in a car cooling system are better controled than those in drinking water?

5/11/2007 1:08:13 AM

.

[Edited on May 11, 2007 at 1:09 AM. Reason : j]

5/11/2007 1:09:46 AM

Quote :

"I'm sure rainwater is way healthier than city water "

You'd be wrong.

City water is treated by some of the most advanced technologies avaliable to make sure it's clean and safe. Rainwater fell through the leftover pollution from rush hour to get to the ground. You figure out which should be cleaner... this time, use your brain.

5/11/2007 9:23:32 AM

isn't this ambrosia's department...

5/11/2007 9:28:35 AM

i think she's the tits department, not the homemade solar-heater department

5/11/2007 9:35:55 AM

i thought she was the one collecting rainwater and shit...maybe it was someone else

[Edited on May 11, 2007 at 9:46 AM. Reason : btw, car radiators have lead in them, so maybe you wanna find something else]

5/11/2007 9:41:45 AM

Trust me when I say this to you.... if you're set on doing this, just pay someone.

5/11/2007 9:43:45 AM

Quote :

"Is it possible that contaminant levels in a car cooling system are better controled than those in drinking water"

Only the cleanest purest water should be put in your car colling system. Buy it at PyeanSkae today!

5/11/2007 9:55:10 AM

This just screams "bad idea" to me.

You'll not only need to collect the rainwater, but you'll have to purify and decontaminate it too. So you'll need a miniature version of the city's multimillion dollar water treatment facility.
Then you'll have to run pipes into your water heater. You wouldn't want to use rubber hoses.
Then you'll have pray that you arent breaking any building codes or violations.


This is certainly not a "project" that I would suggest.


How much is your water bill currently? There's no way that after time invested+money+experience is going to compare efficiently to a $50 water bill in the next 10-infinitity years.

5/11/2007 10:13:38 AM

You water bill cant be that bad, if you want to help preheat the water, they already make readymade kits to set up between the cold water in and the waterheater, thus in summer, ect the water is at least outside temp even at night, in winter you can flip a bypass and drain the panel so it does nto bust.

5/11/2007 8:06:39 PM

I also wouldn't recommend collecting rainwater.

However, if you want to preheat water, all you have to do is run some black tubing on the south side of your roof and have your water system flow through it.
Think of it as water in a garden-hose in the driveway -- hot as hell (maybe not in the morning though!)

5/11/2007 9:55:48 PM

It's scarry how urban people are: Even with air-pollution and the natural particals around which raindrops form, rainwater is very pure. The tricky part is that it doesn't stay clean because it lacks the chemicals that city water has. City water has lots of ugly stuff in it, I'd rather deal with natural flora.

5/11/2007 10:21:54 PM

using rainwater isnt a bad idea, its just a bad idea using rainwater to drink

5/11/2007 11:00:39 PM

Are you trolling or are you just retarded?

5/11/2007 11:00:45 PM

on a semi related note, good eats just did a show on water and how in general its just a bad idea to drink water from nature

i was pissed off at the time cause i thought it was a waste of an episode but now i see it was so I could use this here

5/12/2007 1:42:25 AM

Quote :

"It's scarry how urban people are: Even with air-pollution and the natural particals around which raindrops form, rainwater is very pure. The tricky part is that it doesn't stay clean because it lacks the chemicals that city water has. City water has lots of ugly stuff in it, I'd rather deal with natural flora."

make sure to come back and post your hospital bills later

5/12/2007 3:02:09 AM

http://www.epa.gov/acidrain/effects/health.html

5/12/2007 8:46:56 AM

Quote :

"You'd be wrong."

yes and no...in most cases, rainwater is pretty clean, BUT as it stands, rainfall in polluted areas (wake county being one of the worst, as we're a non-attainment zone) makes for some rainwater i wouldn't, personally, want to bathe in...that said, i'd rather use rainwater than lake/pond/river water

you want really "pure" water? move out into the country and get yourself a well...i grew up on a farm and damn if that water didn't taste better than the filth that comes out of the faucet, and just as good as anything you can buy in a bottle...dirt's the best filter available

5/12/2007 9:27:29 AM

Ok Rainwater unless treated should only be used in a "grey water system" to flush toilets etc.
otherwise you need a a biiig bunch of filtration devices.

I'd show you how mine works but.... we get paid good $$$$$$ for designing them so i can't really post the schematic on the intarweb

5/12/2007 12:33:42 PM

i mean if you wanted to you would only need a pretty simple ceramic or sand filter and a simple uv filter, ozonation, reverse osmosis, or chlorination system. the contamination comes from sitting in the tank, hell if you didnt mind the taste you could get away with just pouring a little bleach in it.

but its a lot easier to use it for everything other than drinking

5/12/2007 2:06:51 PM

Quote :

"isn't this ambrosia's department..."

she posts about it, but its at my house



we have setup rain barrels to catch rain from gutters, but its for non-potable use only (mostly watering lawn/garden); I wouldn't trust anything I'd create to use as drinking water. You have to worry about what it's sitting in, and if thats clean, whether the water was clean in the first place, if your roof was clean, etc.

Now using solar heated water to warm a room isn't as risky of an idea, but the whole "you typically don't need heat in the summer" thing might be a pain :beaup:

5/12/2007 4:16:33 PM

sumfoo1, don't you mean you choose not to post your design? I may respect a choice but I will not respect shirking of responsibility for convention or convenience. Thanks for throwing the phrase grey-water out there, that's the kind of help I need. Anything more technical to offer?

[Edited on May 14, 2007 at 1:19 AM. Reason : vulgarity voided]

5/14/2007 1:15:05 AM

lionheart, that was a good post. I'll look into whater 'good eats' is and try to find anti-natural water stuff.

5/14/2007 1:24:24 AM

arab13, show me your hospital bills for relying on others to keep you safe. Don't assume that the most convenient solution is the best one. Water treatment is 2nd string engineers further hamstrung by 2nd string politicians.

5/14/2007 1:29:25 AM

my dad has installed systems somewhat this, but like others have said, you don't actually collect the rainwater to drink. you use the normal city or well water, and use solar power to heat it.
The effective way is not to heat the water directly, but to use another fluid like anti-freeze in a closed system, and a heat exchanger in the water heater.

you get a set of long, parobolic mirrors and run tubing filled with anti-freeze up and down the mirrors right in the reflection point of the parabola. Then run the tubing down to the heat exchanger/water heater, which where your main water supply comes in.
Using this system, you're still using city water, but you're saving electricity. If you install good insulation, the water can stay warm for days without additional heating. Also, you need to install a saftey shut-off valve because the heating can get so intense if there is a lot of sun it can actually boil the water.

http://www.environmental-expert.com/articles/article193/article193.htm
http://www.eere.energy.gov/buildings/info/components/waterheating/solarhot.html

5/14/2007 8:22:38 AM

no i really can't
1st its not mine to give away.
2nd the post following mine is pretty accurate but most people would use a couple of the filtration systems mentioned to make sure.

if you're using it for heating purposes thats fine you won't need to clean it or anything just leave some chemicals in the loop to keep stuff from growing inside your system, especially heat exchangers/coils.

I don't even know why i posted here in the first place i just said OOOOH! i know that... CRAP! i can't tell. So i apologize for coming off as a dick.

5/14/2007 9:27:55 AM

lion, I want to have a system that uses rainwater for the actual water and for heat exchange. Gotta be safe, not cause standing water (which would get funky and mosquitoey), gotta be free junk parts too. If I can specifically demonstrate the safety of the design and materials, I'm gonna actually build it. I'll have to wash my ass with it for a while before I feel comfortable drinking from it tho, lol. In the long run, I just want to completely cut out city water. (and the city for that matter, fuk all yall and I want to do it with cheap materials. The cheap materials is meant only for transferring the design to Habitat for Humanity or something later on. Personally, I'd drop mega bucks to do this kind of stuff.

5/14/2007 2:10:04 PM

chemicals are for pussies. I think a really good design that has disinfecting sunlight all over everything, rises to good and high temperatures, and goes completely dry sometimes would be quite clean. I am still assuming rainwater is clean, that is true isn't it? Have we fucked that up already?

5/14/2007 2:15:08 PM

parabolic mirrors... I wonder if they could be redirected and used to BBQ a row of sausages!

5/14/2007 2:17:13 PM

http://www.machinocraft.com/images/solar.gif

5/14/2007 2:58:02 PM

dig a well and heat that with solar. have you bothered to calculate how much water you'll need? you'd have to be doing some serious collecting to ensure you never go dry.

personally, i'm of the opinion on demand mini boiler systems (munchkin for example) are the way to go right now for hot water and heat. best mix of cost savings and functionality. solar plumbing technology has come a long way since it first started showing up ~30-40 years ago, but it's still not quite there for "normal" day to day living in this part of the country.

if you're dead set on going completely solar, i would highly reccomend at least using and electric heater as a holding tank so you can flip a breaker and have hot water in a pinch.

the whole using rain water as potable water is just dumb. gray water maybe, but not as fresh.

5/14/2007 8:20:35 PM

i've installed a number or irrigation systems w/ underground tanks storing water off roofs it works well for irrigation but i wouldn't drink it. think of all the crap your roof has on it. anyways one of the systems has about 4000gals of storage and that'll run supply an irrigation system for about 12 complete cycles. also i believe for every 100ftsq of roof with 1" of rainfall you'll get ~1000gals so if you get a big rain you'll need overflow capability.

5/14/2007 10:33:55 PM

rainwater is dumb? holy shit!! people are really like that? PEOPLE! do you know what rain is? It's freshly distilled water for free from the sky: that it is not socially acceptable is a poor reason to fear and reject it. Water vapor condenses upon bit of dust in the upper atmosphere. The rain droplet continues to collect water molecules until it becomes heavy enough to fall as a rain drop.

5/21/2007 2:40:51 PM

oh yea, roofs have crap on them because the materials we make them out of have crap in them. I wouldn't drink water off of the roof unless it had been raining for like an hour. I'm thinking about gardening up on the roof too. I looked it up on google but all they had was a bunch of Lex Luther ski slope type roofs.

5/21/2007 2:46:21 PM

^

1.) learn to edit, not double-post...damn n00b
2.)

Quote :

"do you know what rain is? It's freshly distilled water for free from the sky: that it is not socially acceptable is a poor reason to fear and reject it"

you are dumb...i'm quite sure that most of us are aware of what rain IS, but the problem with your assumption that it will be safe and pleasant to put into your body is somewhat naive...do you know what pollution is? do you know what acid rain is? do you realize that wake county, and most of central north carolina in general, is an EPA non-attainment zone for air pollution? do you understand that drinking straight rainwater is probably not the safest source of water? both city water and groundwater is treated using filters and chemicals (though the methods are different in each case), making them much less detrimental to your body...i really think you should research this a bit more thoroughly

5/21/2007 3:21:17 PM

here are the things

1. your roof isn't something you need to be drinking off of especially not if tar is involved in it.
2. storing water will cause stuff to grow in it.
3. you said it condenses on dust... what if this dust is soot?
4. you'll need alot of surface area to collect the solar energy to heat the water.

5/21/2007 3:42:10 PM

^,^^

Stop letting this ass clown troll your balls off. You lookk like a clown for taking this guy seriously.

5/21/2007 4:27:22 PM

The most interesting thing I found about trolls was Gay Niggers. I think I remember this being an online gaming statement. (like when you get killed by someone who is cheating) I think it is noble to respond to statements with sincerity. Heightened sensitivity for sarcasm expensively ameliorates obfuscation whereas sincerity cheaply and easily relives the burden.

5/29/2007 3:40:59 AM

Quote :

"I think it is noble to respond to statements with sincerity."

and as sincere as i can be in response to your posts, if you think that rainwater is cleaner than city water, then you my friend are an idiot...sincerely. IF rainwater was safer for consumption than city water, any type of city water facilities would be useless.

5/29/2007 5:16:19 AM