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Shower water pump specs?

PostPosted: Fri Nov 18, 2011 8:59 pm
by woytovich
Ok, simple question: what are the MINIMUM specs I should look for in a 12v water pump for a shower? This will be built into a portable unit to be able to be moved around between trailers and vehicles and to use various sources of water (5 gallon can, stream, on demand portable hot water heater) depending on the situation. The pump will be powered by a car battery or other 12v source. I am not looking for the BEST specs... I want to know how LITTLE I can have to get a simple yet decent shower (read fast, short, Navy, trail, field...)

Thanks.

PostPosted: Fri Nov 18, 2011 10:11 pm
by Shadow Catcher
Start with ZODI http://www.zodi.com
Then do a scan on ebay for 12V pumps
I am working to find a pump to pull water out of a lake or stream run it through the two water filters to make it potable and up to CR. The problem I have is getting enough head pressure/lift. I am going to try a Harbor Freight 12V marine pump.

PostPosted: Fri Nov 18, 2011 10:32 pm
by woytovich
I'm not worried about the heater at this point, most of my use is in the summer and air temp water will be fine. I can leave a black can in the sun for the day to get it warm if need be.
i want to know the minimum pump to use. Low amp draw and low cost is the goal but I don't want to be penny-wise and gpm foolish.

PostPosted: Fri Nov 18, 2011 11:22 pm
by Shadow Catcher
ZODI has a pump powered by four D batteries with no heat http://www.zodi.com/Consumer/zodisolarshower.html for about $30. Drop one end in a bucket and pump. Or a solar shower (no power) Advanced Elements Summer Shower 5 Gallon $20 we used a similar one when tenting, and it is easy to add warm water if weather does not cooperate.

PostPosted: Sat Nov 19, 2011 12:31 am
by Trackstriper
Mark,

I've had a shower in my work van for the past ten years. Sometimes I do a little stealth camping when working out of town.

I have a rather standard 2.7gpm Shurflo RV pump....rated at either 45psi or 60psi. It's much more pump than I need volume-wise. For a low consumption shower I'm good with maybe using two gallons of water....wet, soap/wash, rinse, relax a little. 4 gallons is luxurious. I pump the heated water directly, no mixing with cold water to change temps.

The problem that I ran into with this pump was very short cycling....on/off, on/off, on/off, etc. The pump wanted to go but my very low flow shower head said whoa...the pressure switch in the pump would shut it down. I had to buy a small plastic RV accumulator tank, about $35. That allowed the pump to cycle at a more moderate rate. Lesson learned, a bigger pump may have some draw backs.

Do an experiment. Find the shower head you want to use. I used one that had an adjustable flow restrictor, like this

http://www.acehardware.com/product/index.jsp?productId=1272933&kw=shower+head&lmdn=Price+Range&searchId=53476149004

Then hook it up to your shower at home, get nekkid, figure out the amount of shower water you want to work with, then catch the shower water in a bucket or pot for a timed minute. Measure the volume of the catch water. That's the flow that you would be shooting for. If you can match the pump somewhat closely to this flow rate you can probably eliminate the accumulator tank.

If I had to do it all over I would at least look at a 1gpm pump like those from Northern Tool.

http://www.northerntool.com/shop/tools/product_357081_357081

http://www.northerntool.com/shop/tools/ ... _200394109

I don't think it would be hard to get replacement parts for the Shurflo if ever needed, and Northern sells a replacement pump head for their house brand. I don't think I'd be concerned about the amperage rating for the amount of time the pump would actually be pumping, a drop in the bucket....so to speak.

PostPosted: Sat Nov 19, 2011 8:18 am
by woytovich
Thanks all.

Trackstriper: that is the kind of info I was seeking.

i don't want to use the drop-in pump (I actually have a little Coleman one) because it restricts me to a container where it will fit and the switch/wire/hose is a bother to use.

PostPosted: Sat Nov 19, 2011 8:55 am
by Shadow Catcher
I have on order from Bullfinch in the UK a shower point that will be attached to Compass Rose http://www.adventuretrailers.com/showermixer.html along with their gas point. We have a Flotec pump and an Atwood 6gal water heater.
There are a number of ways to get to the same place, a shower, and we may well still take along our sun shower which uses no propane.
RV water pumps pressurize a system and by using an air/pressure tank you can reduce the short cycling.
If I were to design a stand alone system I would probably start with a sized pump a water proof switch, or a marine or RV water pump. You do have to watch lift as most small 12V pumps do not have much.

PostPosted: Sat Nov 19, 2011 9:01 am
by woytovich
Nice...

I really want a portable system. I'm thinking of mounting the pump in a plastic tool box with fittings on the side for power and water in/out. Leave enough room in the box to coil up the basic hoses (enough to go into a 5 gal military water can and then up to shower head height) and a power cord long enough to get to the front of my truck (to the battery). I can carry extensions to those in a separate place.

I like the idea of a "shower in a box". Easy to store, transport and set up.

PostPosted: Mon Nov 21, 2011 8:03 am
by bobhenry
Being the village idiot I saw the word accumulator on Bruce's post and the rusty wheels started turning. If your pump over runs your water saver shower head why not add a small auto or even motorcycle inner tube as a buffer. Remove the schrader valve fabricate a Tee fitting on the valve stem and have the pump feed to the tee fitting. The water will then have the option of feeding the shower or exiting into the tube where it will do two things. Heat in the sun in the black tube and collect and possibly add to the delivery pressure. Drained and rolled tight it will take up about 3 x 3 x 3 inches of storage space.

I gotta go now the nice guys in the white coats are here :roll:

PostPosted: Mon Nov 21, 2011 8:31 am
by 48Rob
A couple years ago my guys were complaining about how much hand pumping was required to winterize homes using a pump up sprayer.

(We winterize the home's fresh water plumbing by forcing non toxic RV. anti freeze through the lines, displacing the water.)

I bought a 12 Volt electric pump.
It is 3.0 gpm, with an auto pressure switch, and manual on/off switch and a 12 Amp hour scooter battery.
I mounted them on a small piece of plywood, strapped down, then placed the assembly in a sealed plastic toolbox.

On one end of the pump is a suction hose the guys place into the bottle of antifreeze, and the other has a hose with an assortment of fittings (to mate with whatever fittings they find at the water heater connections).
There is also a 1/4 turn shut off valve to stop and start the flow of anti freeze.

This setup allows gallons per minute to be adjusted with the shut off valve, while taking advantage of the constant pressure the auto pump produces.

The same setup would work well for showering by simply installing a low flow shower head in front of the shutoff valve/flow adjuster.
In fact, I have this valve/low flow shower head in my camper (though with a much smaller plastic shut off valve, a dedicated water tank, and a large battery bank)) and it works perfectly.
I can have a shower using only 1.5 gallons of water, or a lot more depending on how the gpm is adjusted.
The only downside to this is that at some point you need to re charge the battery.
The guys pump 30+ gallons a day with the 12 Amp hour battery before recharging, so as sized, you should be able to get a week of showers out of a charge.

Rob

PostPosted: Fri Nov 25, 2011 9:16 pm
by Ron Dickey
Rob have you got a diagram or photo's of this set up sounds interesting.

PostPosted: Fri Nov 25, 2011 10:44 pm
by eamarquardt
I like the idea of putting the pump in a tool box with the attendant hoses.

Cool!

Cheers,

Gus

PostPosted: Sat Dec 10, 2011 8:11 pm
by 48Rob
Ron,

Sorry, I lost track of this post...

Here are a couple pictures of the pump setup.
This is "in the toolbox"

<img src="http://im1.shutterfly.com/media/47a1cc31b3127ccefe80fe2cfc0500000030O02AbNGjdu5bMge3nww/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/">

And this is the pump out of the box.
It is all mounted on a piece of plywood so it can be easily removed for cleaning the toolbox.


<IMG SRC="http://im1.shutterfly.com/media/47a1cc31b3127ccefe81df471d9a00000030O02AbNGjdu5bMge3nww/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/">

The green hose is connected to the water line, and the white suction hose is placed in the bottle of anti freeze.
When the pump is turned on, it draws antifreeze though the white hose into the pump, then pushes it through the green hose and the plumbing lines to the faucets/appliances, where the fresh water is forced out by the anti freeze.

To use such a setup for a shower, the white hose goes in a bucket of water, and a shower head is attached to the end of the green hose.

It should be noted that one of my guys who was having a senior moment cut the wires and removed the quick connect couplers so he could "test" them after trying to turn on the pump and getting nothing.
(I don't build things with bare wires hanging out... :shock: )

The quick connect couplers allowed the battery to be disconnected from the pump, and the battery charger connected.

The original 12 Amp hour battery I installed has been changed to a smaller 4 Amp hour battery because the original went bad and they were in a hurry.

He turned on the switch on the end of the pump, and couldn't figure out why it wouldn't turn on.

He "forgot" that the pump, while equipped with an on/off switch, is also a "pressure switch".
When the switch is turned on, it pumps liquid until a preset pressure is reached (usually 35-50 pounds) then the pump shuts off by itself.
It comes on again when it senses a loss of pressure, such as turning on a faucet.
Since we have a shutoff on the end of the green hose, whoever used it last left the valve closed while the pump was on.
Since there was "pressure" in the line, the pump didn't turn on.
As soon as I opened the valve and relieved the pressure, the pump kicked on.

Rob