Reverse Osmosis - Who's doing this in their RV?

A friend of mine just installed an inexpensive ($131 from Lowes - link) R.O. system in his Jayco Pinnacle. He loves the water that comes out of it. He uses it for drinking water only - so he uses a small steel pressurized storage tank (the one that came with the system).

My Ice Maker has been winterized the past 2 months we've been on the road and we've been buying ice and going through a case of bottled water a week, plus a couple gallons of purchased drinking water for the dogs.

I am currently running two whole-house water filters (stage 1: 5 micron sediment / stage 2: carbon). The refer has its own filter, which is currently removed as part of the winterization process, but when installed, that's a 3rd filter in the system for water we get from the refer water dispenser and the ice maker.

This all said, I want to clean up the campground water even more, but just for:

1. Drinking water (people and dogs)
2. Ice making
3. Cooking (but not coffee making)
4. CPAP machines (vs purchased distilled water)

I've been reading up a lot on RO and I'm aware of the waste water (brine) issue. As we only camp in campgrounds (99.9% of the time), access to water and a sewer connection is not a worry for us.

I've used these two sites as my research resource:
- RV Water Filter Store
- Pure Water Products

If I do this, I will not purchase one of the full-pre-made RO systems. I'll buy items piecemeal so I can integrate my existing whole-house filter housings*. At the output of stage 2 of my filtration system, I'll feed the RO membrane, then an RO post-filter (carbon block filter for chlorine/chemical reduction and taste/odor improvement) and then into an RO tank (small pressurized steel tank). From the tank, I'll feed a counter-mounted drinking water tap and the refer ice maker line.

My plan is to co-locate the RO items with my existing filters, behind the utility wall (water pump / water heater / furnace area).

I know two RVers (motorhomes) that create a LOT of RO water and store it in their coach fresh water tank and draw from that with the coach water pump. I have no need for that much RO water and have no plans to make and store that much. As such, my fresh water tank and water pump will not be involved in my RO strategy.

So...

1. Who's using RO in their coach now?
2. What all do you use RO water for?
3. How is your system working out for you?
4. What would you do differently if you were to tweak your RO system?

Footnotes:
* RO systems that use the larger, whole-house size filter housings before the RO membrane, are optimized for 1/4" or 3/8" lines for the demand of RO product water needs. My existing whole-house filter housings are fed by 1/2" PEX and use 1/2" PEX at the output. I feel this is best for my whole-coach water needs, so I want to keep these filter housings. I also do not want a duplicate set of filters/housings for RO. Just no need. This is why I will keep my current filters/housings and split the output to feed the coach and feed the RO membrane.

I have the older GE RO system in my house and have had it since we redid our kitchen some 15 years ago. We fill jugs with this water and bring it with us for the dogs, cooking, and our table top ice maker. I have never thought about adding a system to the RV because we boondock more than use campgrounds. My system has the pre and post filters inside of two twist off tanks that hang down under the RO membrane container that lies horizontal on top of the mounting bracket. The newer GE system has the 3 twist and lock filters in line. I agree with your thoughts about installing this after your current filter process. The RO membrane gets junked up and I can't imagine how bad that would be with out first filtering the campground water. MY GE system is a pain when new or after filter/membrane switches. It takes a long time to fill the reservoir tankard a lot of water is wasted during that process. My system also calls for a bleaching process to sanitize when installing a new membrane. I do not do that just for a filter change. The water taste is obvious right away. Filters do cost money but there are a number of discount websites. After a filter change or membrane change it takes over 24 hours to fill the system and uses a bunch of water that is just wasted. I think the rate is 8 gallons of waste for every 1 gallon that goes to the reservoir tank and then you are supposed to empty that tank and start over. during that process the system makes all kind of noise and water is constantly running. Once up and running, i love the system and it works great. We really used the system with the two boys always filling their water bottles, the dogs and our cockatoo all using that for drinking. The system I have can be bought for around $75 bucks now as it is the older system. a filter pack and membrane purchased together is around $40- $45, pre & post filters are under $25. This system could be mounted after your current filtering as you mentioned and I do not understand why you would by separate pieces.

I do have another suggestion for you. If your fridge does not have water through the door, I would install an extra shut off between the reservoir tank and the fridge inlet. Until a RO system get filled and pressurized, the system is full of air. Most ice maker systems work of off a timed inlet valve. So much water is supposed to enter the ice maker during this time. You would have to wait entire ice making cycles to get all the air out of your system. With the extra shut off valve you would prevent a lot that air. If your fridge has water through the door, then you most like have a two valve water inlet system and can skip the extra shut off valve. In these systems you have one inlet feeding a valve body with 2 valves. The first being for the water through the door which opens the valve when you press the button or lever calling for water. The second valve is opened when the ice maker cycle calls for water and it is opened for a set time. With this system you could bleed the air out of the line by opening the through the door water and you would be making solid ice by the third ice maker cycle.

I also would have a concern about winterizing. You will never get all the water out of the reservoir tank. Not sure what the RO membrane would do with pink antifreeze either, you would almost be forced to disconnect the pre filter, membrane and post filter pieces for the winterization process. Thus making you sanitize the entire system each spring.

I know that you are asking about an installed RV system but thought that I would offer my 2 cents.

I installed an RO system in or Landmark 6 years ago and haven't looked back. On an average 2 week trip, we would go through 4 cases of bottled water, 12-15 gallons of jugs for drinking, cooking, making coffee and tea and watering the dogs. In our rig, there is a panel under the kitchen sink that hides the plumbing and a large area of wasted space. I have the pressure tank hidden in there and the RO system hanging on the panel. I plumbed it to the ice maker while I was in there as well. We enjoy having drinking water available on demand without the added weight or storage issues with hauling bottled water.

As far as winterizing, I drain the system, remove the RO unit, it has 4 quick connect fittings and color-coded, bring it in and set it on the shelf in the shop with the water softener. Any residual water in the pressure tank will freeze but will not do any damage, the bladder inside will expand with what little water remains.

Had no issues with it when we wintered in our rig, had temps down to 17* with a negative wind chill.

Keep in mind, the average RO system will go use 8 gallons of water to make 1 gallon. The pressure tank will hold between 1-1 1/2 gallons of water, we have never run out. When we travel, I leave the pump on and when we stop, we have plenty of water for whatever is needed. The system will shut off automatically when the pressure tank pressure equals the incoming line pressure.

One of my best mods.

I have the RO system hooked up to the fresh water storage tank/pump. We make water for the whole coach. Since we are full-timers in Arizona during the winter, our water is terrible, high in arsenic, fluoride and other solids, comes straight from the well with NO filtering. We use the RO water for everything, dishes, showering, and laundry. We plumb the brine water back through a garden hose to a wash behind our rig, where it perks back into the soil.
Using RO water for dish washing is great, no drying required to prevent water spots, put them in the drying rack and when they are dry, put away., The wife likes the way laundry comes out, and the shower is easier to clean. We use the water straight from the fresh water tank for the Keurig coffee maker also.
Our system is a 5 filter system and makes on average 30 gallons a day. TDS (total dissolved solids) from the well water is in the high 600s to low 700s and after the RO system in the low 40s.

Currently it just sits outside the UDC, one of these days I'd like to mount it inside behind the wall, but with the quality of our water, I have to change the first two filters monthly.
With just the two of us, we make enough water that on occasion I have to shut the system down so we don't overflow the fresh water tank.

You need to be aware that ro uses water to clean the water ro filter. Some people complain more water is wasted than cleaned.

Watts Premeir has a electric pump system that uses the water in the water heater to clean the ro filter. Making the hot water dirtier. Since hot water is generally not used for drinking and eating it should be ok.

I have no experiencd with these systems. I havd recently been investigating and am interested in thd details of peoples usage experience.

John - thank you for your experience and feedback.

I do have an in-door water dispenser in my refer.

I do winterize with air - not with antifreeze. I have not researched winterizing an RO system but my sense is that air will work. Even if 100% of the water in the storage tank can't be pushed out - the small amount remaining likely would not put the tank at risk if frozen.

I will research RO winterization, freezing of the membrane etc. I plan to fabricate a structure that all but the tank mounts to and that can be removed from the system in minutes. As with my current filtration system, I will move the RO system from coach to coach as I get new demo coaches.

Ed - that's a lot of years experience with RO in your RV. Thanks for the feedback. I noted with interest, your comment of leaving the water pump on while traveling so the RO system could make water while you drive. Great idea.

For me however, I never sanitize my fresh water tank and only use the water in it on travel days for hand washing and flushing the toilet. I like your idea though. Perhaps it's time to clean my fresh water tank and begin to use it as feed water for the RO system on travel days.

Bill - your usage is similar to Ed's - making RO water and putting it to the fresh water tank. I like the thought of having nice water for `00% of our needs but that is a LOT of waste (brine) water. I may start small (drinking/cooking/cpap) and if we love it, scale the system up for the next coach later in 2017. Thanks for the feedback.

Bohemian said:

You need to be aware that ro uses water to clean the water ro filter. Some people complain more water is wasted than cleaned.

Watts Premeir has a electric pump system that uses the water in the water heater to clean the ro filter. Making the hot water dirtier. Since hot water is generally not used for drinking and eating it should be ok.

I have no experiencd with these systems. I havd recently been investigating and am interested in thd details of peoples usage experience.

Click to expand...

I have read where some people push the brine water into the fresh water tank for reuse in non-drinking applications. I'm not interested in doing that. I'm also leary of making RO water into the fresh water tank until I put a better tank level sensor in so the RO making process can be halted when the tank reaches a specific level.

As for cleaning the RO membrane - I have done little research on that. I would not be interested in doing anything tricky like plumbing the water heater through it. I'd likely replace the membrane or remove it for cleaning per the mfr's instruction.

So like you - I am still researching it all. Hope you too can benefit from this thread.

Thanks, Jim, for starting this thread. After just experiencing the water quality in the deserts of New Mexico, I'm also interested in an RO system. I saw someone from the Quanah rally that had a large blue tank, but I'm not sure if it was RO or a water softener.

Rex - the large blue container you saw was an On-The-Go water softener.

UPDATE: I spoke to Michael Kidd today about my RO plan and he sort of talked me into taking a whole-coach approach to RO. So I've shifted gears a bit. Going to cost me more $$ but I'm making the system as portable as I can in order to move it to the next coach. Left in this coach will be fresh water tank floats (2) that will be used to tell the system to make RO and to stop making RO - based on the level of RO water stored in the fresh water tank.

Still working on optimizing my whole-coach RO design, then will send it out to a a few people to critique before ordering parts. This is going to get interesting!

jbeletti said:

Rex - the large blue container you saw was an On-The-Go water softener.

UPDATE: I spoke to Michael Kidd today about my RO plan and he sort of talked me into taking a whole-coach approach to RO. So I've shifted gears a bit. Going to cost me more $$ but I'm making the system as portable as I can in order to move it to the next coach. Left in this coach will be fresh water tank floats (2) that will be used to tell the system to make RO and to stop making RO - based on the level of RO water stored in the fresh water tank.

Still working on optimizing my whole-coach RO design, then will send it out to a a few people to critique before ordering parts. This is going to get interesting!

Click to expand...

Jim,
Please keep us updated on the progress and share the finial plans. I am looking for a new project since the solar project is almost done on my Big country. This looks like it could be great project.

Steve

sjandbj said:

Jim,
Please keep us updated on the progress and share the finial plans. I am looking for a new project since the solar project is almost done on my Big country. This looks like it could be great project.

Steve

Click to expand...

Sure thing Steve. Looking at this for days now - I see 3 price points one can expect, based on 3 different use cases.

I'll toss a couple rounded up numbers out there:

1. $150 to $200 - Standard off-the-shelf complete RO systems for lower usage (25 Gallons per Day or less)
2. $300 to $500 - Large capacity (making and storing RO water) system, larger pre-filters etc.
3. $500 to $1000 - Largest practical capacity (for an RV) system, larger pre-filters and 1 or more post filters, boost pump, tank level float control etc.

I'm looking at option 3 at this time. I will make the system as portable and quick to uninstall as possible, leaving behind only the tank level floats (inside the fresh water tank).

jbeletti said:

Rex - the large blue container you saw was an On-The-Go water softener.

UPDATE: I spoke to Michael Kidd today about my RO plan and he sort of talked me into taking a whole-coach approach to RO. So I've shifted gears a bit. Going to cost me more $$ but I'm making the system as portable as I can in order to move it to the next coach. Left in this coach will be fresh water tank floats (2) that will be used to tell the system to make RO and to stop making RO - based on the level of RO water stored in the fresh water tank.

Still working on optimizing my whole-coach RO design, then will send it out to a a few people to critique before ordering parts. This is going to get interesting!

Click to expand...

What changed your mind from a smaller system to the larger one?

After chatting with Jim at supper last night, I am now interested in a system. It will be interesting to see how this project goes.

Bones said:

What changed your mind from a smaller system to the larger one?

Click to expand...

Dave - it was a few things. It started off with the RO water production rate and RO storage amount with the 25 GPD (gallons per day) system I was contemplating. Using if for drinking (us and pets), cooking, CPAP, water bottle filling, making a gallon of tea etc. - it became evident that the system would be inadequate.

I then began looking at higher production rate systems and large storage tanks. This led me to using the RV fresh water tank for RO storage. At that point, it was much a leap to take to whole-coach RO water production and usage.

Additional benefits to the whole-coach approach is spot free dish washing, spot free shower door glass, spot free faucets, better for your skin and just better on all the plumbing and fixtures.

So the whole-coach approach eliminates a few components in the previous approach and adds a few more. I will likely go with two 75 GPD RO Membranes where the brine water of the first membrane feeds the second membrane. Michael uses this method and it was recommended to him by Rick at the RV Water Filter Store. In this manner, he cuts his brine production by about 50% - making his system more water efficient.

My system design is in an INCOMPLETE DRAFT status at this time, but I'll share it as-is to give readers a feel for it.

I shared this design with Michael and he suggested that I split my tank floats. He suggests I place 1 in the gray tank my brine water will go into. Maybe place that float at the 3/4 full position. He suggests I place 1 in the fresh water tank at the 1/4 full position. In this manner, the system will stop making RO water if the gray tank is nearing full. Most times, my gray tanks are open, so this won't be an issue much. With the float at the 1/4 position in the fresh water tank, the system will start RO water production when the tank is getting low. I may vary these float positions prior to actual install.

Your diagram looks good Jim. Do you plan on keeping the normal water fill port on your tank. and do you plan on boosting your pump? I also know that a lot of campgrounds don't like water dumping to the ground either. Would you have a back-flow preventer on the last brine connection for a just in case event?

Check out this deal
http://www.ebay.com/itm/271555919071?rmvSB=true

Jim:
I worked on hospital large scale RO systems used for dialysis centers. There we had about a 90% reject to product ratio, but some of the reject was recycled back into the RO input lines.
The main thing that I can say about RO is the human palate doesn't like water that is TOO pure. Like distilled water, it is very bland. Most commercial water bottlers ADD SOME MINERALS BACK IN TO THE PRODUCT WATER (Polishing) to give the water an acceptable taste.

Besides water source particulate filtering, I use a PUR water pitcher in my refrigerator door for my ice and drinking water needs. The PUR filter has a polishing section in it.

For my situation of extended camping at various campgrounds, I settled on a 5 micron carbon filter and water softener for general use and bottled water for drinking. The reason I did not go for RO is because it removes the good chemicals and nutrients from the drinking water.