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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Scott & Heather on November 15, 2012, 07:21:46 PM

Title: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 15, 2012, 07:21:46 PM
Having to fill my 100 gallon fresh tank every three days this winter so as to stay disconnected from park water spigot. Takes sometimes 15 minutes to fill tank. I've walked away and already overfilled and flooded my luggage bay twice now. Any recommendations? I don't want to just merely install an overflow tube as that will make an icy mess around the coach. If I retrofit an auto shut off fuel nozzle from northern tool for $60 will that work?


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Title: Re: Fresh water tank fill auto shut off
Post by: Sean on November 15, 2012, 09:13:59 PM
Scott,

If you already know how long it takes to fill, then probably the cheapest, quickest, and easiest solution is a mechanical garden-hose timer, such as this one:
http://www.walmart.com/ip/16564903 (http://www.walmart.com/ip/16564903)

Set it for, say, 95% of fill-time and then top off manually.

That said, if you really want positive shut-off on fill, you'll need a ball-float valve in the tank.  Systems that work on back-pressure, such as the fuel-nozzle shut-offs, will not be calibrated properly for a vented tank.

-Sean
http://OurOdyssey.BlogSpot.com (http://OurOdyssey.BlogSpot.com)
Title: Re: Fresh water tank fill auto shut off
Post by: TomC on November 15, 2012, 10:19:52 PM
My 130gal tank is under my bed. So if I walk away, my bedroom gets flooded.  It's only 15 minutes out of your life. Just stay there and watch it-seems simple? Good Luck,TomC
Title: Re: Fresh water tank fill auto shut off
Post by: gmcbuffalo on November 16, 2012, 08:23:26 AM
what about rigging up a electrical solenoid valve to the water inlet.  The solenoid would close when activated by a low voltage current signalled from the tank monitors Full sensor.    You could also put in two sealed screws in to the tank so that when water reaches them they complete the voltage circuit to the shut off solenoid or signal a buzzer to warn you.
Title: Re: Fresh water tank fill auto shut off
Post by: Len Silva on November 16, 2012, 08:32:06 AM
The problem with standing outside in the cold with water running is that you just have to go pee so bad you can't stand it.
Title: Re: Fresh water tank fill auto shut off
Post by: goutoe on November 16, 2012, 09:27:57 AM
I seem to have that problem forgetting to shut of water around the house, I bought a cheap little timer at radio shack I clip it to my belt, I have had it several years it has saved me alot of greif, I suppose my cell phone has a timer but probably too hard to figure out how to use it! HTH. John.
Title: Re: Fresh water tank fill auto shut off
Post by: usbusin on November 16, 2012, 12:24:25 PM
What is wrong with overflow tubes?  I have 80 gallons under the bed and 40 gallons under the couch; both have over flow tubes to the outside.  Shut the water off when it starts to overflow.  Just my way and I'm sure others as well.
Title: Re: Fresh water tank fill auto shut off
Post by: Iceni John on November 16, 2012, 01:06:48 PM
Shouldn't the overflow/vent go to the outside anyway?   If you topped up your tank in cold weather, then had hot weather later, you're going to lose some of the water from its expansion.   This happened a few years ago one winter when I topped up my fuel tank, a few days later we had a 90-degree day (in winter!), and diesel was coming out my tank.   The yard's owner didn't see the humor in it.   Damn, winters are tough in SoCal, especially when the temperatures plummet down into the 70s . . .

John
Title: Re: Fresh water tank fill auto shut off
Post by: usbusin on November 16, 2012, 02:23:20 PM
Iceni John asks;

Shouldn't the overflow/vent go to the outside anyway?


I would think so, but apparently TomC's doesn't per above.
Title: Re: Fresh water tank fill auto shut off
Post by: Lin on November 16, 2012, 06:07:45 PM
One could make a fairly elaborate system to deal with this issue, but it seems there are better ways to spend resources.  Sean's suggestion of a cheap sprinkler timer is about as complex as I would let this get.
Title: Re: Fresh water tank fill auto shut off
Post by: robertglines1 on November 16, 2012, 07:25:37 PM
we use a stock (cattle) tank level shut off on the steam engine tank. Would have to rig a external mini tank to mount it in reading same level as your tank.We have ours mounted inside our storage tank and hook a garden hose to it.  Bob   PS not on bus ! we are mostly pole to pole and stay warm! Steam Engine!!!  Water supply tank... ;D   Not that young and hardy.  Some type of mechanical shut off.    Bob
Title: Re: Fresh water tank fill auto shut off
Post by: wg4t50 on November 17, 2012, 04:53:50 AM
Geez, Poor design, run the over flow outside and carry a pee bottle with a big coat.
Dave
Title: Re: Fresh water tank fill auto shut off
Post by: robertglines1 on November 17, 2012, 05:44:07 AM
Dave; modified my post. Was refering to some kind of mechanical shut off. We have Steam Engines and use that at shows to leave a hose hooked up to supply tank to keep it from running over.  I don't do cold winters in bus! Worked outside in midwest all my life. No reason to do that anymore.   Bob
Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 17, 2012, 10:28:24 PM
Hmmm all good stuff reading on here. Thanks for understanding the whole "gotta go" when you're standing in the cold thing. Sooo true. I like the sprinkler timer shut off idea. I also know I need a vent/overflow tube and might just have to do that. If I overflow though, I floods already super soggy ground and I'm standing in mud to fill my tank now. It's muddy on that side of the bus unless it gets a chance to dry out. Thought this would be easy. I'm not averse to standing there the whole time, but I get distracted easily by something else and end up inadvertently wandering off like a lost child. 45 minutes later I remember . And we have Noah's ark all over again. Sheesh. I'm a mess...I know.


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Title: Re: Fresh water tank fill auto shut off
Post by: Dave5Cs on November 18, 2012, 02:21:24 PM
They probably make a "Nap' for that, LOL

Dave5Cs ;D
Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 18, 2012, 03:37:29 PM
In reality I could just hang a water alarm from Lowe's in the tank at the height I want it to alert me. 85dB of loud will get my attention....but automatic shut off...just is a cool concept. I think out of the box guys..that's what built our bus...thinking out of the box...so I'll keep scratching my head on this one. Thanks...
Title: Re: Fresh water tank fill auto shut off
Post by: Oonrahnjay on November 18, 2012, 07:31:56 PM
    Toilet fill float and valve????
Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 18, 2012, 08:14:23 PM
    Toilet fill float and valve????
Funny you ask. I scratched my head at lowes staring at the kits in the toilet section for probably 35 minutes trying to figure out a way....came up with nothing.


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Title: Re: Re: Fresh water tank fill auto shut off
Post by: zukmancdr on November 19, 2012, 07:07:01 AM
I know in the fishtank business they have a float valve that you can hook up a 1/4" line  into it and it will shut the water off.

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Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 19, 2012, 08:20:53 AM
That's basically what I'm looking for...it would work...so would the toilet fill kit..if I could retrofit, but remember, we're talking about filling a 100 gallon tank..at 1/4" it would in theory take twice as long as the 1/2" line I'm currently using...right? I just thought someone out in the RV world came up with this already...
Title: Re: Fresh water tank fill auto shut off
Post by: Iceni John on November 19, 2012, 09:12:58 AM
A 1/4" line will take you A LOT more than twice as long to fill than a 1/2" line!   Don't even think about filling a 100 gallon tank through that  -  it's not much larger than a drinking straw!   FYI, it takes me at least ten minutes to fill either of my 110 gallon tanks from 65 PSI city water through a 5/8" hose, using either a 3/4" direct tank feed or a 1-1/4" gravity fill.

John  
Title: Re: Fresh water tank fill auto shut off
Post by: TomsToy on November 19, 2012, 09:17:30 AM
If I was going to do it, I would use one of these.
http://www.homedepot.com/Plumbing-Plumbing-Parts-Repair-Toilet/h_d1/N-5yc1vZbqps/R-100554467/h_d2/ProductDisplay?catalogId=10053&langId=-1&storeId=10051#.UKpl2eRIhOJ (http://www.homedepot.com/Plumbing-Plumbing-Parts-Repair-Toilet/h_d1/N-5yc1vZbqps/R-100554467/h_d2/ProductDisplay?catalogId=10053&langId=-1&storeId=10051#.UKpl2eRIhOJ)

Water connection is in the bottom, water comes out around the top.  I would add support at the top.  Install in tank if possible or in a 4in PVC pipe that is tied to the tank at the top and bottom so that the water level in the pipe is the same as in the tank.  You might have to throttle the water flow because the fill water will have to flow through the bottom connecting pipe into the tank.  You still need an overflow.

Another way is to salvage the pressure switch and solenoid from an old washing machine.  Tie the pressure switch pressure tube to the tank at the bottom with the switch located so that it opens at the high water level.  Break the 120 VAC going to the solenoid through the float switch.  These solenoids even come with a hose connection.

HTH

TomsToy
Title: Re: Fresh water tank fill auto shut off
Post by: Len Silva on November 19, 2012, 10:15:05 AM
There are lots of inexpensive float switches that will install in a small (3/4") hole in the top of the tank.  Here is just one example  http://www.coleparmer.com/Product/Vertical_float_switch_nylon_nitrile/WU-43301-22?referred_id=778&gclid=CLLDyp_R27MCFQu0nQodQ1oAxw (http://www.coleparmer.com/Product/Vertical_float_switch_nylon_nitrile/WU-43301-22?referred_id=778&gclid=CLLDyp_R27MCFQu0nQodQ1oAxw)

I have found that a standard 24 volt AC sprinkler valve will work quite well on 12 volts DC.
Title: Re: Fresh water tank fill auto shut off
Post by: Sean on November 19, 2012, 02:56:56 PM
... we're talking about filling a 100 gallon tank..at 1/4" it would in theory take twice as long as the 1/2" line I'm currently using...right? ...

No.  A 1/2" line is FOUR times as large as a 1/4" line -- remember that cross-sectional area of a circle varies with the square of the diameter.  So at the very best, it would take four times as long.  In practice, it takes even longer, because as the diameter decreases, the ratio of the surface area of the pipe to the volume of the pipe also increases, and flow rate at a given pressure will be lower.  That calculation depends on the material of the pipe, number of bends, etc., and is more complex than we need to go into, other than to say you should figure it takes more like five times as long to deliver a give quantity of fluid through a pipe half the diameter.

To elaborate on what John wrote, at most city water fills, it takes us 20 minutes to fill our 135-gallon tank through a 5/8" hose (the smallest diameter in the system).  If we added a 1/4" restriction to that line I would figure it to take more like an hour and a half, up to two hours.

This is one reason why I tell folks to make sure they understand orifice diameters when they are buying valves.  Lots of solenoids on the market, for example, will have 1/2" inlet and outlet fittings, but a much smaller orifice, some as small as 1/8".

FWIW.

-Sean
http://OurOdyssey.BlogSpot.com (http://OurOdyssey.BlogSpot.com)
Title: Re: Fresh water tank fill auto shut off
Post by: Lin on November 19, 2012, 05:23:39 PM
I think Rube Goldberg once had a drawing for solving this exact problem.  I will try to find it.
Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 19, 2012, 05:29:49 PM
Cool! Never did the math. But yes, it fills pretty quick on my 1/2" line, but took forever on my previous 1/4" line. So this is why. Going to look into the toilet valve again as well as the washing machine valve.


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Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 19, 2012, 05:30:59 PM
The cole partner solutions looks good too. I do wish I could come up with something that didn't need power.


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Title: Re: Fresh water tank fill auto shut off
Post by: Mex-Busnut on November 19, 2012, 08:21:57 PM
We just used a small float valve like you might use on a stock tank. it is about the size of one you might find in your home toilet's water tank.
Title: Re: Fresh water tank fill auto shut off
Post by: Lin on November 19, 2012, 10:53:40 PM
  As someone mentioned, you could use a trough float valve like:

 http://www.kencove.com/fence/Jobe+Water+Valves_detail_VJR.php (http://www.kencove.com/fence/Jobe+Water+Valves_detail_VJR.php)

You would have to get into the tank to do it, but you could do it from the top and then reseal it.
Title: Re: Fresh water tank fill auto shut off
Post by: Scott & Heather on November 20, 2012, 07:25:35 AM
That item is cheap too. Nice find. I think I've found several good solutions here. Thanks again guys. Now to implement...