off-grid water system freezing.

Lefty Wright
Lefty Wright Solar Expert Posts: 111 ✭✭
I'm in heavy timber which makes it difficult to locate pv panels near the places where power is needed.

My biggest winter problem is burst water piping.

I pump from my well into a storage tank and then gravity feed to a booster pump in the garage, where my pressure tank is installed.

Even after building an insulated closet around the water system and wrapping the pipes they often burst. Especially at the brass valves.

Last winter my pump housing broke.

I doubt that it gets as cold on my California mountain as it does in Canada or in the Dakotas.

How do you guys keep your pipes from freezing without adding heaters?

Comments

  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: off-grid water system freezing.

    Hi Lefty, can we get a few more details about what power/heat you have available? Grid, wood, PV only, etc?

    Eric
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
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  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Ditto Eric's question,,,

    Is it the pipes and valves that are freezing or the tank system(s)?

    Tony
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: off-grid water system freezing.

    I don't have a well or freezing weather--but is there anyway you can have the pipes drain back so they are "dry" most of the time? (small tank in home, lines from cistern/well are only full when the pump/gravity feeds home tank?)...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: off-grid water system freezing.

    The last post I think has the right idea. I have a cabin with a well that I installed a 12/24 volt well pump. I found that it drains back naturally into the well. Its maybe 30 feet of head. I pump into a water tank that's in the cabin and use a boat fresh water pump to provide pressure. After I fill the tank, it drains back into the well. I also layered pipe foam, bubble wrap and foil wrap around the pipe. Never had it freeze. I have used this setup for years in temps as low as -15. Hope this helps.
  • Lefty Wright
    Lefty Wright Solar Expert Posts: 111 ✭✭
    Re: off-grid water system freezing.

    Here is what I've got; Power is from PV's mounted on a tower about 50 feet from the house. Right now I've got only 250W of PV and a 220A batery bank at 12V. But I am upgrading and after the spring breakup I'll have 500W of PV and 440Ah bank. I'll probably stay at 12V because of my 12V appliances.

    I have a 400W inverter that I use for cf lighting. From October to June I have enough snow or cold temp that I don't need refigeration.

    My water storage tank is at a higher elevation than the house so it gravity flows to the house. The outlet of the tank is buried and the filler has been valved so it can be drained and I don't have trouble at that end.

    The water line comes up through the concrete slab in 1½" sched 40 pvc and about 8" above the floor is a plastic ball valve (main shutoff).

    The pipe reduces to 1" sched 40 pvc above the shutoff valve and above that is a hose bib (at 24" above floor), a brass check valve and a brass valve to drain the system above check valve.

    A booster pump then charges the pressure tank which feeds the house.

    I havn't had any trouble with the piping after the pessure tank, just with the piping from the shutoff valve to the pressure tank.

    The capacity of the pressure tank is not great enough to maintain a constant water flow on the cold nights.

    It's an attached garage and I heat with wood, exclusively. The garage walls are insulated but the uninsulated steel roll up door is only a couple of feet from the water line. Yes, this should be insulated and the spring re-set to compensate for the extra weight.

    I have thought of replacing the sched 40 with sched 80 pvc. I don't know how much difference that would make.

    It would be possible to drain the system every night.But I don't think that's practical.

    I wrapped the pipes and they froze. I built a closet around the whole system and insulated it and they still froze.

    The good news is that when the pipes burst the water freezes and I don't loose the water in my storage tank.

    The brass parts are the first to freeze. Some mornings I have to soak rags in boiling water and wrap them around the valves to free up the flow.

    All of California is not tropical.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Lefty,

    Eric and I have a pretty through thread on the subject on this forum.

    http://forum.solar-electric.com/showthread.php?t=1831&highlight=heat+tape+pipe

    I have designed and built a simple automatic drain back system, supplimented with heat tape.

    http://www.heatline.com/kompensator.htm

    http://www.deanbennett.com/wintergard-heat-tape-prices.htm

    http://www.morelectric.com/pipe.htm

    http://www.thehardwarecity.com/thc/?sku=2844066

    In short the system automaticilly drains back except when it call for water. The other pipes are insulated and heated with low wattage heat tape that draws ~3-5 watts per foot. Available in 12vdc (Kompensator)

    If you need more information, post it here or send me a e-mail.

    Good luck.

    Tony
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: off-grid water system freezing.

    Lefty, as you have it described, it looks like the problem is at about 8 inches to 2 feet off the ground. right by the shut off and pipe reducer and hose bib.
    does the hose bib look like this?
    http://www.masterplumber.net/images/hb10.jpg

    hb10.jpg

    If so I bet this is the problem, it transmits the cold straight to the inside....which isn't heated....

    Heat will help. since you only have CFLs and 220 ah batts you can not (don't want to) use a small incandescent light (5W) for heat, right?

    I also am reading that you are having trouble right now! How low have your temps been so far?

    Eric

    ps its minus 15 C right now for us, about 5 above F.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Eric's picture is of a "frost proof" hose bib. The closing valve is a number of inches into the wall, so that (if allowed to drain) there is no water outside to freeze. If you don't have a frost proof, get one. If you have one consider installing a shut off to the hose bib with a drain so that you can close it even further from the outside wall. (the frost proof has to be installed with the outside end tilted slightly down so it can drain. If it doesn't it will freeze regardless)

    Eric is right, in that the cold copper will conduct the cold into the other pipes. ( if you don't need the hose bib in the winter, consider adding a valve and a union and cast it loose for the winter).

    In any case you will find a way to make this work. If nothing else, add more insulation to all the piping. Closed cell foam pipe insulation comes in big sizes so you can put bigger over smaller. Also, small piping will freeze way faster than smaller pipes. I'm rambling now so I'll stop!

    Good luck,

    Icarus
  • Lefty Wright
    Lefty Wright Solar Expert Posts: 111 ✭✭
    Re: off-grid water system freezing.

    Thanks for the response and Happy New Year, guys!

    Tony, that was good info on heat tapes. I'll keep that in mind for the day when I'm no longer an electrical minmalist.

    Eric, Your temps are a little lower than mine. The times I have the most trouble are clear nights when the sky effect acts like a blast freezer.

    My hose bib does not extend to the outside. I use it to draw drinking water for my water dispenser. (I don't drink the water from the pressure tank)

    Johnnybr58's use of spray on foam sounds like something I'll do.

    Since the system has been breaking every other winter the piping is now mostly couplings and short nipples. I will totally rebuild the system with sched 80 pipe and use Johnny's spray foam idea.
  • System2
    System2 Posts: 6,290 admin
    Re: off-grid water system freezing.

    One last thing - I forgot to mention that I put a 8 inch piece of PVC pipe around my well line so that it acted as a container for the foam. So first pipe wrap closed cell insulation, then the PVC which I filled with foam, then the foil bubble wrap (had some extra) around the exterior. At least that's what I remember doing (been in place for around 10 years).
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Lefty,

    One thing to note on the semi-conductor heat tape, is that you can cut it to length, any length, so you could, for example use a 4' piece that would burn a max of 12 watts. If you only have short lengths of pipes that are prone to freezing it might be a cost effective solution. Also, if you put the tape on an super insulate the pipe, it won't run but a few minutes an hour to keep the pipe above freezing.

    Stay warm, (we're -22 tonight,, but I'm away in the balmy PNW!)

    Icarus
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: off-grid water system freezing.

    Lefty, can you post a pic or 2? these would help immensely...

    back to the original query: if the piping is in a partially insulated garage, there has to be a 'conduit' for the cold to get at the pipeing, if the 'closet' did not cure the freezing there has to be something different.

    Before I would permanently enclose the piping in PVC / foam, I would go back to step 1 and look for something that let the cold into the closet.

    the cheap foam tubres may be your best quick fix. recommend electricians tape if you are going for 2 layers.

    when you re-jig the patchwork perhaps move the brass / copper fittings a good bit higher off the floor and further away form the door.

    One winter the basement door was not fully on the latch, and one of the dogs pushed it open about a foot, probably about 5 hours at -35C. The waterline is about 4 feet away and it froze where the 1 1/2 inch poly exited the concrete. It was a good test of our hi efficiency furnace which is 4 feet from the water pipes.... point being is that even in an insulated, heated area pipes can freeze easily.

    HNY

    Cheers
    Eric
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: off-grid water system freezing.

    My money is on the concrete floor passing the cold to the pipe. Does the floor finish up to the 1½" sched 40 pvc pipe. Maybe you need to add insulation between the pipe and the concrete floor.
  • Lefty Wright
    Lefty Wright Solar Expert Posts: 111 ✭✭
    Re: off-grid water system freezing.

    I have noticed that when my pipes break the cracks always seem to start at the brass valves. The part of the piping close to the floor never freezes. ?????

    I like the idea of that heat tape. If I stack all the brass fittings (hose bib, drain valve and check valve) close together and lay a couple of feet of heat tape on them (haven't figured out how to totally insulate the valves since they require access.) they shouldn't freeze.

    Sure glad an info source like this exists.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Lefty,

    It sounds like the pipe coming through the floor benefit from the heat of the earth. The brass also conducts heat (cold) better than the sched. 40 plastic.

    If you follow the links to the heat tape sites, they show how to wrap and insulate the valves. One simple way is to put the valves in a $.99 styrofoam cooler, with the right holes cut in them.

    Icarus
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: off-grid water system freezing.

    "One simple way is to put the valves in a $.99 styrofoam cooler, with the right holes cut in them."

    maybe along those lines a foam type beverage glass insulator with a tie to make the open end tight to the pipe would work. slide it on and tie it when not in use and untie it and slide it off to turn the valve. this also allows the heat tape to be at the valve. just a thought.
  • System2
    System2 Posts: 6,290 admin
    Re: off-grid water system freezing.
    icarus wrote: »
    Lefty,

    It sounds like the pipe coming through the floor benefit from the heat of the earth.
    Icarus
    For years I used ground heat to keep a waterline from freezing. The camp was on posts, up off the ground. Buried a 4 inch PCV straight down 4 feet into the ground and brought the waterline up through that. NO INSULATION BETWEEN THE TWO, but lots of insulation on the outside of the 4 inch PVC, ABOVE GROUND ONLY.
    Ground heat entered the PVC underground, the insulation above ground kept it in, the warmth circulated naturally in the air within the PVC and the waterline never froze. There was no ongoing cost to prevent freezing and if the power went off - - so what, who cared :)
    Wayne
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    They do make a foam valve over for hose bibs. It doesn't have a back to it, but there is no reason you can't make one out of styrofoam.

    Icarus
  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    Re: off-grid water system freezing.

    Or heck even try wrapping the whole end in regular 4 or 6 inch bat insulation. That should keep the heat in the pipe. Am I understanding the water only moves in this pipe when your pressure tank drops and it is getting back up to pressure? How often does this happen? I had once case that if I left the water dripping (like once every 5 seconds) it never froze, but that was freezing after the pressure tank so any small water movement brought in warmer water to the line which kept it from freezing.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • Lefty Wright
    Lefty Wright Solar Expert Posts: 111 ✭✭
    Re: off-grid water system freezing.

    Brock, the water moves only when I pressurize the tank, every couple of days.

    Right now a storm is coming and temps have risen to only 10 degees or so below freezing. We are expecting 2 feet of snow today.

    My freezing problem only happens when it's clear.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: off-grid water system freezing.
    My freezing problem only happens when it's clear.

    so it's radiant losses, not conductive? tried lining the shed with the silver colored bubble pack insulation (like some car windshield/dashboard covers) ? less messy/itchy than fiber insulation, and may "brighten" it some if you have to work in there often
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  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    Re: off-grid water system freezing.

    Same problem I had, I would go out and shovel snow around the base of the house to warm up the crawlspace and keep it insulated from the colder air outside. It was amazing how much of a difference that made, I had a remote thermometer down there and without snow covering it would get about +20 from outside, with a good snow covering it would stay in the mid 30's. I assume the ground would warm up the space a bit, at least more then the air cooled it down.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: off-grid water system freezing.

    Snow is also good to keep the wind out of the crawl space. Same effect, only better looking than the old farm hay bales around the skirting. I have been know to spray the outside of the house with a fine mist of water to give it a thick glaze of ice. Does wonders when the wind his howling through the cracks. The ice does sublimate fairly quickly, that is evaporating without melting in a day or so, depending on the wind.

    Icarus

    PS. You can make some cool ice sculptures in the deal!