Temporary solar hot water setup...

RandomJoe
RandomJoe Solar Expert Posts: 472 ✭✭✭
in Energy Use & Conservation #1
So I came home yesterday to find my natural gas has been shut off. From the cryptic notes on the work order they left, there's a leak in the medium-pressure (I assume that's what the MP meant) "yard line". (My meter is at the back of the yard, so I would have thought the "yard line" would be the run from meter to house, which surely wouldn't be medium pressure? Perhaps it's the tap from the main to the meter?)

This means I have no hot water. Other than that, not a big deal - too warm for the furnace, and I'll finally be compelled to try hanging clothes on a line to dry! :D But I don't care that much for cold showers, and the gas company said it'll be 10 days - at best - before they fix it! :cry:

I just finished a shower and was lamenting the fact I'd used up the last of the hot water when it occurred to me I have hose taps on either side of the water heater - the washer H/C taps are right beside the heater - and it's nice and sunny and hot here. What if I run a long hose out in the sunny back yard, get a small water pump (I could even run it off the solar power system! ;) ) and circulate through the hose to heat the tank.

Now, before I go trying to find a pump and some extra hose, anyone know how effective this might be? I don't need 140 degree water, I believe most garden hoses wouldn't like that. If I can get the tank to 90-100 deg I'd be happy! Functionally I don't see a problem, but want to be sure I'm not going to do longer-term damage to anything...!

I wouldn't leave this running unattended (have to have a door cracked to get the hoses outside anyway) and would insert a temp sensor to watch water temps to make sure things don't get too hot...
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #2
    Re: Temporary solar hot water setup...

    I would just worry that even a 100' of hose laid out in the back yard would not take much of a chill off a 50+ gallon hot water heater.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #3
    Re: Temporary solar hot water setup...

    It will work. Trust me.

    My cabin water is pumped from the lake, up about 50' of black hose that lays across the lawn (obviously not a permanent install). The water in that line gets very hot in the Summer sun. Even water in an ordinary green garden hose will pick up a lot of heat. It may take a while to heat 50 gallons, but it will heat arm enough to shower with so long as ambient temp is not too cold and you can keep the speed of the water through the system slow enough so that it picks up heat.

    Look for a "pony pump" which often have hose connections on them: http://www.princessauto.com/pal/product/5771233/Utility-Pumps/110V-%22Pony%22-Pump You can put a valve in-line to adjust the rate of the flow so that the water picks up enough heat.

    Then you're going to wonder "Why am I paying the gas company to heat my water anyway?" and will embark on a new project to make the solar hot water collector more efficient and permanent.
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #4
    Re: Temporary solar hot water setup...

    Possibly not. It obviously wouldn't be a very *fast* warmup, but I know that water sure does get hot in the hose if left sitting without flowing for very long.

    It might require a LOT more tubing, I wonder how much a water solar panel has inside. I've never seen one up close before.

    Heh. For that matter, I could run the hose on the roof - it would *definitely* get hot up there, but probably damage it if left when not running...

    My tank is "only" 30 gallon, and really I don't need much heating. This last shower my leaving-water temp sensor only showed 91 degrees. It was comfortable. My showers are quite short (had three since the gas was shut off and only now down below 90 in the tank) so I don't need a "full tank of hot water", I'm good if I can take the edge off!

    Perhaps I'd be better off just buying a small electric water heater, plugging it into the (unused) 220V dryer plug and letting that heat the tank a bit. The tinkerer in me would have more fun the other way though... :) Also, hose and a circulating pump I can use elsewhere, normally not much use for an electric water heater around here!
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #5
    Re: Temporary solar hot water setup...

    Ah, thanks Coot! I was typing the last while you posted.

    That's exactly the pump I was looking for, but didn't know the name. I'll go searching for those here. I've found some others that may work, but wow the prices... If I can find the one like you linked for $100 that'd be great. Lowes and Home Depot have an actual hot water recirc pump about that size, but they want $200 for it!!!

    Guess I have something to do this afternoon... :)

    Yeah, I've already thought about why I'm paying for the gas... It sure does heat the house nicely in winter, though. I just can't believe the very nonchalant attitude they had when they told me it'd be over a week to resume service! The electric company busts their behinds getting service restored, to the point of running temporary lines through backyards if necessary. (Actually, I have one of those out there now, for a neighbor's house!) Gas may be more problematic to temporary in, but good grief...
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #6
    Re: Temporary solar hot water setup...

    That natural gas pipeline explosion about 10 miles from my home (September 2010) probably has everyone in the gas industry a bit on edge at this point.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #7
    Re: Temporary solar hot water setup...

    Some places might call it a utility pump. Here's CT's 12 Volt version: http://www.canadiantire.ca/AST/browse/3/HouseHome/Plumbing/WaterPumps/PRD~0623568P/Utility+Pump+12V.jsp?locale=en
    It says it will run off a solar panel. Probably 80 to 100 Watts or so. Sun shines, pump runs, water heats. :D
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #8
    Re: Temporary solar hot water setup...

    Well... It's working... Sorta!

    Found a utility pump at Tractor Supply, and bought some more hose. I now have about 230 feet of hose stretched out, of course a fair portion is used just getting out to the yard but there's quite a bit laying in the sun.

    I'm getting 3 - 3.5 degF rise coming back. Not sure how fast the water is moving. Haven't seen a rise on the leaving side of the tank yet, although the way a water heater works I really shouldn't until it's all uniformly heated. Shouldn't be too much mixing inside the tank.

    Only problem is the pump. It's running HOT! I have a fan blowing on it which has so far kept it on this time, but the first run it shut off on thermal. Kill-A-Watt says it's pulling 2A, which is its rating so... Guess I'll see how it does! :)

    Ah, now just about up to 4 degree differential. Hey, the leaving-tank temp rose 0.2 degrees! :D

    Edit:
    And BB you may have a point. I've wondered whether I really have a leak, or if they are just upgrading the whole area. About 1/2 mile away they've spent MONTHS pulling a lot of new yellow plastic gas line down a half-mile stretch of road. They're now even with my block, maybe it's our turn... Better not take months to get gas back though!

    Edit2:
    Just went of on thermal again. Ran a LOT longer this time though. I suppose this time waiting for it to cool isn't wasted, the loop in the yard will get that much hotter while it's not flowing! :p

    I don't think it likes pushing against pressure - when I turn the sink faucet on, the pump speeds up! Perhaps I should get a real hot water recirc pump... Grangers has a nice one that is surprisingly cheaper than the Home Depot one, but of course they aren't open on weekends...
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #9
    Re: Temporary solar hot water setup...

    And next you'll think "if I covered that hose with some clear plastic I could keep the heat in and raise the temp even more".

    Next thing you know it's flat black paint and soldered copper pipe on metal sheets under thermal glass surrounded by R5 insulation panels back and sides ...
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #10
    Re: Temporary solar hot water setup...

    Actually, I was thinking about a big spool of PEX - only two connections, smoother inside, perhaps better flow? :) I'd trust it a lot more than garden hoses...!

    I wouldn't mind having some real water heating panels, only problem is I worry my roof couldn't handle many/any without some major reinforcement. I'm not willing to give up the yard permanently!

    I thought of a somewhat nutty way to eliminate some of the hose running into the house - use the existing house plumbing! :) I'm letting the cold water piping carry water from the tank out to the back yard, then connecting the hose to the spigot there. Might have helped the pump some - current is down a bit, and it occasionally ramps up to a higher speed. Of course that probably means I'm moving more water. Not sure how much effect that'll have, soon as I changed the setup there are some clouds that keep shadowing the yard!

    But I do have the tank up to 97 degrees now! :D One more warm shower... :D
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #11
    Re: Temporary solar hot water setup...

    Don't leave PEX out in the sun; it isn't UV resistant.
    Okay there may be one variety of it that is, but the ordinary stuff deteriorates in sunlight.

    The black PVC for potable water is a good option.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #12
    Re: Temporary solar hot water setup...

    as i recall a plumber telling me years ago that pvc is not uv rated either and he recommended painting the pipe to protect it if it is exposed to the sun.
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #13
    Re: Temporary solar hot water setup...

    Ah, didn't know PEX would deteriorate. That would be a problem!

    I made two changes, one or both which gave me quite an increase in water flow. First was removing 50 feet of garden hose by using the house piping, second was reversing the pump - it is now drawing from the long hose, pushing into the tank, rather than other way around. I'm not getting nearly the temp differential - just 0.5-0.8 deg - but the leaving tank temp was climbing much faster so still more effective. The pump is running cooler as well and staying on.

    I got the tank temp up from 93.5 to over 98 in less than two hours of runtime (between the pump shutting off and me rearranging things) so it looks like I can keep taking at least lukewarm showers this week, long as I can get home soon enough each day to rig up this contraption and get some sun.

    Doggone it, now I have crazy ideas of maybe putting one or two water panels on the roof to circulate the water heater...! As well as this crazy setup works, I imagine a real panel would do just fine for my limited hot water needs. (Except for winter - I like long, steamy-hot showers in winter!) Ah well, what's one more project on the stack... :D
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  • firerescue712
    firerescue712 Solar Expert Posts: 95 ✭✭
    #14
    Re: Temporary solar hot water setup...

    Watch this video. It is with black tubing on the roof. 104 degree water without any pumps. I am not sure how you would plumb the water into your storage tank. It is possible, though. http://www.youtube.com/watch?v=Z6ffSB4_6pU
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  • mejustme
    mejustme Registered Users Posts: 17 ✭
    #15
    Re: Temporary solar hot water setup...

    Hi

    I have been playing around with directly powering 12 volt appliances.

    One idea that i have yet to try but will in the next few weeks for things like this (temporary hot water) is to get a 12 volt water boiler (various wattages from 120 watts to around 200 watts) and just plug it into a 12 volt panel.

    You need to discount the voltage over 12 volts in working out the panel size but it should work. mybe use a couple of panels in parrallel.

    Boil the water in a 3 litre or so thermos.

    I will get a small electric kettle to start experimenting (one about 90 watts) to start and just plug it into my 200 watt panel.

    I will get a 80 watt panel soon and use that with my 200 watt panel and a 200 watt boiler I have and also get a 120 watt boiler and about a 150 watt one and use various combinations of existing 50 and 200 watt panels and coming 80 watt one and see what works best.

    Should be able to get enough water for a shower in a couple of hours with the largest setup/combination.
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #16
    Re: Temporary solar hot water setup...
    firerescue712 wrote: »
    Watch this video. It is with black tubing on the roof. 104 degree water without any pumps. I am not sure how you would plumb the water into your storage tank. It is possible, though. http://www.youtube.com/watch?v=Z6ffSB4_6pU

    Wow! 500 feet of tubing on the roof?!? Wonder how it is secured... Sure would hate to see that big coil sliding off! I had fun keeping the garden hose from sliding off, but then my roof pitch is pretty steep.

    I need the pump, since I want to charge the water heater tank during the afternoon for use at night (before bed) and in the morning. The one I got seems to be working fine, and my solar power system can handle it easily. Only hangup I have now is that I'm not willing to trust the hoses unattended. If I could simply wire the pump to a relay off my automation system, I'd have plenty of hot water - just run it at noontime and all afternoon. My luck, though, one of the garden hoses would give way and I'd have a flood... It'd probably be the end in the house, too! :p

    I moved my lines to the roof, but too late to see real results. The thermal energy from the sun appears to fall off even faster than the PV generation as the sun sets! I did see over 100 degrees briefly earlier in the afternoon with the hose laying on the grass, hopefully I'll do better on the roof tomorrow.

    I love it when an impromptu project comes together! :D
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #17
    Re: Temporary solar hot water setup...

    Two days on, now. Yesterday the system wasn't nearly as effective - had a thin overcast all day! :( I did manage to get the tank temp up 10 degrees - 84 to 94 - which was something, but had to listen to the annoying whine and scream of the pump for many hours! Definitely not the right pump were this a more permanent fixture, there are far quieter options available...

    Also identified a couple other problems.

    First, the water *smells* like it ran through a garden hose! :D Didn't think about that... I'm only using it for showering, so no big deal, but I'll have to flush the tank well once I get the gas back on.

    Second, the water heater loses about 10 degrees from 5-7PM when I can't heat anymore to 5AM when I take my morning shower. I suppose thanks to the flue up the center. Might try blocking that with something, long as I remember it before relighting!!! Guess this is one case where an electric tank is actually better - would hold heat longer than a gas tank.

    Still haven't had a cold shower yet, so worthwhile so far! Last two showers have been 85, not too bad - about like getting into a pool. Might be tougher the rest of the week - forecast is for cooler (low-70s) weather and more clouds, not sure how much heat I'll be able to get in the couple hours after getting home from work.
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  • Joe_B
    Joe_B Solar Expert Posts: 318 ✭✭✭✭✭✭
    #18
    Re: Temporary solar hot water setup...

    I have a stupid question, why dont you just buy a bottle on compressed natural gas from a supply house and hook it up to your water heater. Any welding supply store or forklift supply house will rent you a container of CNG. When it is empty, you can return the tank.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #19
    Re: Temporary solar hot water setup...
    Joe_B wrote: »
    I have a stupid question, why dont you just buy a bottle on compressed natural gas from a supply house and hook it up to your water heater. Any welding supply store or forklift supply house will rent you a container of CNG. When it is empty, you can return the tank.

    But, what fun would that be? :D
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  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    #20
    Re: Temporary solar hot water setup...
    RandomJoe wrote: »
    Second, the water heater loses about 10 degrees from 5-7PM when I can't heat anymore to 5AM when I take my morning shower. I suppose thanks to the flue up the center. Might try blocking that with something, long as I remember it before relighting!!! Guess this is one case where an electric tank is actually better - would hold heat longer than a gas tank.

    Definitely true, that chimney connection is a big thermal siphon. My electric tank is wrapped in 6" of fiberglass insulation and is on a timer. It is off from 10 pm until I get in the shower at 5 am and it is still very hot. It is then on from 5 am to 7 am, not on again until 6 pm. On weekends when we're working outside and don't get into the shower until 4-5 in the afternoon we'll still get 2 hot showers before it runs out, even though the heating element has been off since 7 am.

    Moral of the story, add some insulation to your tank if you don't have it already. You'll have to be more careful since its a gas unit.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #21
    Re: Temporary solar hot water setup...
    Joe_B wrote: »
    I have a stupid question, why dont you just buy a bottle on compressed natural gas from a supply house and hook it up to your water heater. Any welding supply store or forklift supply house will rent you a container of CNG. When it is empty, you can return the tank.

    Because I didn't know I could do that! :) But do they come with a regulator suitable for the purpose? Or would that be another item to rent/buy? I'm also a wimp when it comes to gas - much as I like using it, I *hate* working on gas lines!



    Well, the weather definitely got the better of me today! *sigh* Didn't get over 65, and was heavily overcast with a slight mist all day. Miserable day... No solar hot water today, and when I got home, the water tank was at 78 degrees. By the time that got to the shower (of course at the other end of the house!) that was a shivery shower. No way I want a true cold-water shower! :cry:

    So I gave in. What's the point of having money if you don't spend it, right? Went to Home Depot and bought a 4 gal under-sink water heater for $215, and a couple fittings for my washer hose setup, and am now circulating water through that to heat the main tank! :p Unfortunately, between the heavy overcast and it being 8PM I can't run the heater off the solar panels. Perhaps tomorrow there'll be sun. Once the battery bank is floating, long as it's sunny I could run the water heater straight off the panels! :D

    The little water heater gives me a 3-4 degree rise if I just constant-flow through it, but I'm tired of hearing the whine of that little pump motor so I'll cycle it which gives me larger differentials. Let the little tank heat for 10-15 minutes, then pump it into the big one. Already up 4-5 degrees at the outlet of the main tank after just 20-30 minutes. (I also don't have lines running outside this way, either!)
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  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    #22
    Re: Temporary solar hot water setup...
    RandomJoe wrote: »

    The little water heater gives me a 3-4 degree rise if I just constant-flow through it, but I'm tired of hearing the whine of that little pump motor so I'll cycle it which gives me larger differentials.
    I'm hearing a fair bit of whining, myself. :D
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  • Ralph Day
    Ralph Day Solar Expert Posts: 1,022 ✭✭✭✭
    #23
    Re: Temporary solar hot water setup...

    At that temp I'd whine too!:roll:
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #24
    Re: Temporary solar hot water setup...
    ggunn wrote: »
    I'm hearing a fair bit of whining, myself.

    :D:blush:
    Yes, I'm not well suited to "roughing it". I could handle a day or two, but a WEEK or TWO? Especially when the problem was man-made. I strongly suspect the people hired by the electric company to do some horizontal boring nicked my line. They coincidentally replaced a neighbor's line the same day the leak was found! Of course no one will own up to that...

    Anyway, I had fun playing with ways to heat water this week. I might even try building/buying a real solar water panel at some point, I've been impressed at how well it can work.

    In the end, though, KISS rules. When I got the little electric water heater I was so fixated on getting the big main tank warm that I missed the obvious! :roll: I just valved off the main tank, connected the little electric unit to the washer faucets, and use it directly! Now I can turn it on and 30 minutes later take a HOT shower - just not for very long! ;)
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  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    #25
    Re: Temporary solar hot water setup...

    I was about to suggest just that. A camper's water heater is 6 gallons and works very well for a Navy shower, and will even work for a while if you want to let it stream, so 4 gallons for a Navy shower should be fine, too.
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  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    #26
    Re: Temporary solar hot water setup...

    Oh, and don't forget to insulate your big tank like I suggested on page 2. Solar or not it will pay for itself big time.
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #27
    Re: Temporary solar hot water setup...

    The crisis is over! :D The gas company came by Thursday afternoon and replaced everything in remarkably quick fashion. It helped that they used it as an opportunity to move the meter. All the older houses around here have the meters at the back of the yard, with a (remarkably large!) low-pressure line underground to the house. They showed up, dug two holes - one at the house where the line enters the wall, one back at the old meter. Removed old meter, slid the new yellow poly-pipe "main" line inside the old line, connected it to their main, mounted new meter - done in about 3 hours! Someone else came by a few hours later to turn it on, check for leaks, relight the water heater.

    It was a fascinating learning experience. I never knew that natural gas filtering through soil will over time turn it black. The guys doing the work showed me my old line was surrounded by several inches of it. (Around here it's normally a clay / sandy color.) They said it had been leaking for YEARS to do that much!

    The little heater did nicely for the few days I needed it. Now I'll have to find someone who wants to put a water heater under their sink... :) (Actually not sure I'd inflict this particular model on anyone. The reviews are pretty bad, many complaints of leaking after just a year. I figured surely it'd last a few days to a week anyway! ;) )

    I've thought about insulating the gas heater, but never bothered - the outside of the tank is never even warm, it's actually cool to the touch unless it's very hot in the garage. Not sure how much a blanket on the outside would help.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #28
    Re: Temporary solar hot water setup...

    interesting. now was that leak before or after the meter, aka you paid for it or their loss?
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  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    #29
    Re: Temporary solar hot water setup...

    I have no idea, and they didn't dig up the line so not sure they knew. It was found by someone whose job is to walk the mains with a detector "sniffing" for leaks. The forms they left, and the fact they weren't charging me for repairs (the low-pressure yard line is the customer's responsibility), suggested it was in the high-pressure side of the meter, but the guys doing the work said the company had been taking care of low-side leaks lately as a chance to move the meter up to the house.

    My bills certainly weren't high enough to make me think anything was wrong, if it was after the meter I'd say it was a *very* small leak! However, the "black dirt" was all around the line leading to the house, which suggests to me it was there. If it was in the high pressure line I think it would only have made it to the old meter location, where the HP line comes up separate from the LP line.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #30
    Re: Temporary solar hot water setup...

    ok so you feel the free leak fix by changing the line to go to the new location will offset any extra costs the leak may have cost you.

    i did learn something here as far as the ground turning black due to a leak. was he anymore specific on how long it takes for a leak to create the blackness to the soil?
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  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    #31
    Re: Temporary solar hot water setup...
    RandomJoe wrote: »
    Now I'll have to find someone who wants to put a water heater under their sink... :) (Actually not sure I'd inflict this particular model on anyone. The reviews are pretty bad, many complaints of leaking after just a year. I figured surely it'd last a few days to a week anyway! ;) )

    I've thought about insulating the gas heater, but never bothered - the outside of the tank is never even warm, it's actually cool to the touch unless it's very hot in the garage. Not sure how much a blanket on the outside would help.

    Too bad it isn't a decent model and that you aren't close, I've been meaning to get a 4-6 gallon heater to put under the sink in one of our bathrooms. Too far from the main heater to allow you to ever get hot water in the time it takes to wash your hands.

    Mine was cold to the touch, too. Don't let it fool you. After adding the insulation now when I stick my hand under the insulation it is always very warm. All heat that is now being trapped where it used to escape into the air.
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