Solar Hot Water Pre-heater?

[Anonymous No.1280360]

Sup, /diy/?

I have a lot of black plastic water pipe. In the summer, I turn off my electric water heater because it costs about $45-$100/month($540-$1,200/year) to run, depending on who is in my house.

However, I do prefer to have at least a luke-warm shower from time to time. What does /sci/ think about this design?

Essentially, the 3 valves can redirect water to the large coil of black piping in the summer and in the winter water is redirected straight through as normal. The black piping is removed int he winter and drained so it won't freeze and bust. Or, it's placed in a large bed of fresh hot horse manure where it will continue to function for making hot water. I even have a large 55-gallon, plastic, rain barrel. I could coil the black piping into it, fill it with water, paint it black, and sit it in the sun too. That way the water in the barrel will act as additional thermal mass to extend the amount of hot water being created a great deal.

I figure I can use this simple system as a hot water pre-heater and as the sole hot water heater while using the hot water tank as storage, (it's quadruple insulated for this sort of purpose already.)

The only problem I can think of is the piping getting too hot and melting just enough to allow the water pressure to burst a leak.

Ideas, thoughts?

[Anonymous No.1280407]

good idea, we always do this with our garden shower. it gets pretty hot, but as you can imagine, you only have o "pipe" full of warm water, after that the water gets colder (if you have a hot tank (like a black rain barrel) you could extend the amount of hot water a bit.
rest coming soon

[Anonymous No.1280418]

Considering you can boil water over an open flame in a paper cup, I don't think you have to worry about your plastic melting enough for the water to escape.

[Anonymous No.1280424]

>>1280407
Yeah, but I'll also be putting "charged" hot water from the pipe directly into my hot water tank before it goes to the shower. It usually keeps water warm for about 48 hours at the very least, if it's not being used normally and is turned off. So, I'm betting that I can heat water, run it into the tank, repeat until I get hot water at the shower. Then I'll have a bit of a cycle that will allow for a 10 minute shower. Adding the rain barrel to that would make it even better.

However, I am pretty conservative with water in the first place. I simply wet down, turn the water off, soap up, then rinse off really quickly. I actually only need 5 gallons or less of water that way.

But, guests are usually water hogs and take 30 minute showers and come out looking like cooked lobsters.

[Anonymous No.1280426]

1.Get big compost pile, big enough to give off substantial heat
2. Get compressor/pump
3. Get pipe
4. lay pipe extensively through compost
5. Pump cold water through pipe, should draw heat through compost into the pipes water.
6.Gather hot water
7. Connect hot water pipe to your water tank/boiler
8 Receive more hat water than before.
9???
10. Profit!!!

[Anonymous No.1280430]

>>1280418
Yeah, but is the paper cup completely sealed and already under pressure? That's the point.

[Anonymous No.1280433]

>>1280407
for the pressure just fill it with water and then get around 6-7 bar of pressure in it, because when you connect it to the water-net, the water just flows back into the net if the pressure is too great, but it should really withstand 6-7 bar.
the last problem would be, that when you use your normal hot-tank, you would have to think about a solution to get a hottank of water from the pipe only when the pipe is hot.

for example: you have hot water in your tank and in the pipe. now you shower, until the water of the tank and the pipe is new, cold water. when the cold water arrives in your shower, the water in the hot tank is could, but only the water in the pipe will heat again.

[Anonymous No.1280439]

>>1280426
That is what I'll be doing in the winter. Though, I think I'll be using metal piping instead because hot manure gets really fucking hot sometimes.

[Anonymous No.1280446]

>>1280424
if you do that manually, there is no problem.( the filling of te tank)

[Anonymous No.1280454]

>>1280439
Pipe/Metal same basic idea laid out.

Use a good conductor like copper.

[Anonymous No.1280461]

>>1280433
You'd be using a lot of water to do that. Just having a normal hot water tank, turning it off, then showering should leave you with enough hot water to take one shower where cold water just starts at the end when you finish.

[Anonymous No.1280481]

I have a 100 feet long 1 inch diameter black plastic water pipe. That will hold just slightly over 4 gallons of water. That's not too bad actually for me for one shower.

>>1280454
Of course. it's expensive as shit though and increasing every year.

[Anonymous No.1280487]

>>1280481
Scrap yard, old buildings for copper wire and shit man, if you're determined enough to get it you can get it easy and at the end of the day the energy saved will make you break even at least.

[Anonymous No.1280512]

>>1280487
lol No, you can't do that either. One, you can use wire. Two, everyone and their brother already scraps copper. You're more likely to get you legs broken doing shit like that. Stealing and scrapping copper is a big fucking business and those guys really don't like people working in on their business. At least not in this area. Shit, if people find out you have copper water pipes in your house, you'll more than likely come home one day to find all of it torn out and completely gone with a shit load of water spewing everywhere.

It's far better to simply buy it.

[Anonymous No.1280524]

>>1280512
>One, you can't use wire.

fixed

[Anonymous No.1280527]

>>1280512
Then break their fucking legs.

Or be a pansy and use something else.

[Anonymous No.1280573]

>>1280527
or, be a tough invincible 4chan faggot behind a computer screen in a basement

>It's far better to simply buy it.

only correct choice

[Anonymous No.1280636]

black plastic water pipe is rated for psi at a certain temperature, i think it is like 20C or so. normally it is buried and protected from substantial temp swings.

if it is filled with water at pressure and then heated substantially not only will the pressure increase from the water expanding but also the plastic will weaken, I think that stuff is polyethylene which is a thermoplastic.

i don't know where you live but black objects in full sun can get up to 60C or higher in the summer in many places, and i doubt a coil such as the one you propose would last very many temp+pressure cycles.

my money is on it failing either the first or second summer, depending on your water pressure, the rating of the pipe and your climate.

[Anonymous No.1280659]

Revisions.

[Anonymous No.1280670]

>>1280636
Mine says, "100 PSI @ 73F". It's pretty thin-walled piping too. Luckily, it's very cheap.

[Anonymous No.1280981]

Here's one I designed about 2 years ago. This one uses copper in the heat exchangers and the one in the sun is enclosed in a insulated box with 2 panes of glass. The tubing uses water with anti-freeze so it can be left out in the winter without freezing. Check valves keep the pressure from getting to high.

It doesn't need a pump and uses thermosiphon design with 1-2 inch diameter lines instead.

[Anonymous No.1281156]

>>1280981
And how do you cycle the hot water from the solar exchanger to the water tank?

[Anonymous No.1281181]

>>1281156
Sorry for the late reply. The answe is "thermosiphon". Warm/hot liquids rise and cold ones fall. The loop is made so that a thermosiphon cycle takes place. as soon as the sun heats the piping in the hot box it rises up and is cooled by the water tank at the top and thus falls again to the hot box.

[Anonymous No.1281198]

>>1281181
Also, the wider the diameter of the piping the better the thermosiphon flow.

[Anonymous No.1281203]

>>1281156
http://en.wikipedia.org/wiki/Thermosiphon

[Anonymous No.1283073]

Do this and get methane too.