plumbing suggestion (longish)

bobofthenorth · December 13, 2007, 03:54:04 PM

It struck me today that we have a very useful feature on our coach that I don't think a lot of people incorporate into their plumbing. When we bought this bus it had both a 120 gallon fresh water tank and a 20 gallon drinking water tank. At the time I thought that was foolish overkill but I have grown to really like it and down here in Mexico it is invaluable. At home we often run into water that we don't want to drink. We deal with that by always keeping the drinking tank full of water from a known source that we trust and it is surprising how long 20 gallons of water lasts when you only use it as drinking water.

When we bought the bus we knew we would be bringing it to Mexico and I struggled for a long time to figure out how I was going to get purified water into the drinking tank once we were down here. I had all sorts of wild ideas about cutting holes in the floor so I could pour water into the storage tank. Then it struck me that I already had a system in place but that system only works by accident - in other words it was more by luck than good planning that I ended up with a system that works. Those of you that are still laying out your plumbing may want to benefit from my good fortune.

We have an intake water manifold. The city water comes in through a check valve and then through a filter. The location of that check valve is important - if it was further downstream this system would not work. After the filter the water goes to a three valve manifold - one valve carries on to the house system, one valve goes to fill the main tank and the 3rd valve goes to fill the drinking tank. Obviously we have separate pumps for both drinking and fresh water. Shortly after we bought the bus I put 3-way ball valves ahead of each pump so that I can easily winterize both systems. I just throw the ball valves to the winterize position, stick the attached hose in a jug of pink stuff and turn the pump on. The eureka! moment was when I realized that my winterizing valves also give me the ability to fill the drinking water tank.

To fill the drinking water tank I simply open both the house and the drinking fill valves on the intake manifold. That way when I pull fresh water in through my winterize hose it goes to the house system but can't go anywhere there except back to the intake manifold and from there over to the drinking water tank. A couple of days ago I tested the system by running a 5 gallon jug of purified water through the manifold and into the drinking tank. Purified water is virtually free down here - $1 for 5 gallons - so I dumped the 1st bottle to flush the drinking tank and then ran 4 bottles into the drinking tank.

Life is good - la vida es buena y dulce.

kysteve · December 13, 2007, 07:07:50 PM

genius

thanks, bob of the north, I have been wondering about something along these lines and you just filled in the blanks for me.

kysteve

gumpy · December 13, 2007, 08:15:31 PM

Wouldn't it be easier the just install a drinking water filter with a .5 micron carbon block filter designed to filter out all the bad stuff? Then you don't need two pumps, and extra tank, etc. Just install the drinking water fixture on your sink, and run it off the main pump. The filters can run about $30 each, but you probably only need to change it once a year.

That was the plan for us, but with the 1 micron carbon filter I have on the main system, it's never been a problem and I never actually got it installed. We always fill water from known municipal systems, or from wells we trust and have only had questionable water once, in Missoula, MT, but that was just because it tasted like crap. I'm sure it was safe. I haven't taken the bus to Mexico.

bobofthenorth · December 14, 2007, 11:13:50 AM

I don't know much about water filtration Craig so I'll freely admit I'm in over my head here but, if I was going to design a system, I don't think I would want to trust filtration alone. I've seen some systems set up with UV light and obviously a system could be designed that would work. I think the issue is little wee things like parasitic amoebas that need to be killed because they are too small to filter. But I don't know that for sure. 2 tanks is a low tech way to accomplish ready access to safe water.

gumpy · December 14, 2007, 11:57:34 AM

That's true. But I was amazed by how much some of those filters actually remove. Most claim to remove cryptosporidian cysts. The really good ones claim to remove all sorts of nasty stuff. I don't know. Maybe it's just marketing.

You could also use reverse osmosis to produce your drinking water, but that wastes about 8 times what it produces. I know some have used these systems in their buses.

I have a filter I use for backpacking that claims you can produce drinking water from sewage. That's not one I'm going to test

but I've used it to filter creek water with no ill effects. On the other hand, I've been drinking creek water all my life with no ill effects.

Lee Bradley · December 14, 2007, 02:34:18 PM

I am planning on installing a 5 gallon water cooler on the kitchen counter with the jug secured in the cabinet above. I can carry as many extra 5 gallon jugs as I think I will need a the basement. No worries about contaminating a built-in water system; worst case throw out the stand and jugs and start fresh.

boogiethecat · December 14, 2007, 10:25:44 PM

I too have a 20 gallon drinking water tank along with it's separate pump and spigot in the sink. I LOVE it. I fill the tank prior to a trip with Reverse Osmosis water from my home system. I then fill my 150 gallon main tanks with the hose from anywhere I am, and don't worry about how good or bad the water might be. It's only for showers, toilets, and dishwashing at that point.

I am a strong advocate of RO water. It's clean, pure, inexpensive, and systems are easy to purchase (can you say "Home Depot") and install. The water created is very clean, good tasting and above all good for you.

Yes RO systems do "waste" water... depending on the system you have it will make 3-8 drops of "waste" water for every good drop it produces. But what you do with that "waste" makes all the difference... most installers simply route it to the drain and in that case, yes it is wasted. But I ran a 1/4" drip irrigation hose from the RO "waste" port out to my veggie garden which loves all the extra minerals and "free" water. No wasting of anything.

Gumpy, the problem with carbon block filters is (1) bugs and germs are technically only stopped by a .2 micron filter or smaller, which won't do much but clog quickly on tap water. A decent RO system has one of these as it's final filter, but a lot more too. Typically it goes like this:
A fiber filter to catch the crud and small frogs that come thru the pipes, then a carbon filter, then the RO section, then finally a second carbon "finishing" filter to get anything that the first three missed. The nice thing about RO is that the "waste" water coming out of it is actually cleaning the RO membrane as it works, so you can go as much as a year between filter changes with little degradation of the water output quality. In any case, all of that stuff is a lot of equipment to put on a bus, a carbon filter by itself (in my humble opinion) won't do a decent job, and the two tank system is simple, foolproof, and perfect. I totally recommend it.

Cheers
Gary

Lin · December 14, 2007, 11:18:20 PM

I think a good activated granulated carbon filter is fine for use at least on any municipal water system. They remove heavy metals, bugs, and chemicals. I see bottle water as a scam. Municipal systems must meet much higher standards than bottle water. Added to that, a huge percentage of bottled water is just filtered city water anyway. But I do think you should filter your city water to remove whatever has been put into it to kill everything else. If you are to be in areas of dubious water, there are filters that will work too. Reverse Osmosis is one system. I have seen systems advertised that claim, not only to remove bacteria, but virus as well. There are ceramic filters that you can just clean when the flow decreases too much. I read that the US Embassies around the world use high quality filters. UV light is also available for an an extra kick. There are even UV pens you can mix around in your water to massacre anything that made it through alive. However, if you have a separate drinking water tank, why not use it for a dedicate supply (although some claim that we absorb almost as much pollutants from just showering as drinking)?

muddog16 · December 15, 2007, 05:49:53 AM

As long as we are talking water systems, Bob you mentioned winterization, I understand low point drains and empting the systems, but has anyone decided to use electrical heat tracing on all of their water lines feeding through out the bus? There might be a time where the weather might require that. Just a thought.

Pat

bobofthenorth · December 15, 2007, 07:44:13 AM

YMMV but on our system there is enough "waste" heat in the bays to allow us to run in pretty cold weather without worrying about the plumbing freezing. I don't know exactly what "pretty cold weather" means but its probably -15C and as far as I am concerned that's too bloody cold for me for the rest of my life. The waste heat comes off the lines from the ProHeat, off the ProHeat itself, off the water heater and there is even some heat generated by activity in the black & grey tanks.

Of course keeping the lines from freezing also depends on their physical location. In our case that means entirely within the confines of the original coach. If some of your lines are actually exterior to the coach then all bets are off when it comes to freezing.