Has anyone added whole-house reverse osmosis to class-c Sprinter?

[FollowTheSun]

Wife and I are about to begin new ventures as we ready to purchase a class-c Sprinter, lease our home, and drive into a year of travel as we search for a new homestead. While we feel confident about our class-c MB Sprinter decision, we have not yet decided which make. We are persuaded toward a 2016/17 single slide unit with the diner, closet, and queen bed on the port side. However, I wish to add a few things to the motorhome which I believe will greatly enhance our boondocking comfort. While most of the things I wish to add are quiet simple, three items concern me because of available space or necessary coach modification, these are: 1) 300 watts roof-mount photo-voltaic, 2) whole-house reverse osmosis for freshwater, and 3) shore AC power surge protection.

Here I would like ask if anyone has added whole-house reverse osmosis to their class-c Sprinter? If so, how did you accomplish this and where did you install the filters? Any suggestions about how to best proceed?

[nomad297]

The relatively cheap type of RO system that might fit somewhere in your RV will waste a minimum of 4 gallons of water for every gallon of clean water produced. This will tax both your fresh water supply and your gray tank -- a problem for you if you are not with full hookups. Also, almost ALL RO systems require a minimum of 40 psi to operate. I don't think an RO system will work well with the pump for your fresh water.

Bruce

[gspot01]

Originally Posted by nomad297

The relatively cheap type of RO system that might fit somewhere in your RV will waste a minimum of 4 gallons of water for every gallon of clean water produced. This will tax both your fresh water supply and your gray tank -- a problem for you if you are not with full hookups. Also, almost ALL RO systems require a minimum of 40 psi to operate. I don't think an RO system will work well with the pump for your fresh water.

Bruce

X2. I have one of those (5-stage ro/di unit) for my house and homebrewing operations. Imo it's overkill and/or inappropriate for rv application.

For the rv, my solution was to purchase two of the standard filter canisters and in the first, put a spun sediment filter, and in the second, a carbon block filter. Sediment filter keeps most of the dirt out of your system, and the carbon filter removes most of the objectionable tastes and chlorine. I hook this up between the city water supply and rv input.

Since you said you'd be boondocking however, you'd simply fill your water tank with this filter and obviate the need for an under-the-counter solution.

Sent from my SM-T320 using Tapatalk

[FollowTheSun]

Thank you for the comments. I suppose I should have clarified my question. I understand how RO systems work and the various economy ratios associated with booster pumps, filter configuration, tank fill time, and brine waste. I use an RO system with a battery operated pump on my mountain camping property, with both sediment and carbon filtering because of turbidity, mineral content and high pH. I also have read many discussions debating the pro and con of doing whole house installs … it is an active debate with many points on both sides. I apologize for starting that debate here … that was not my intent. Rather, I was hoping to focus on the ability to accomplish a neat and tidy physical install into a Sprinter class-c.

[Handydc]

RO is an over rated filtering system. There are simpler systems that are far less costly that do just as good a job giving you clean water.

[Ron, Debra & Foxy]

I think that by filtering your freshwater inline from the hose to the fresh water tank + your onboard water filter can adequately offer a quality water supply.

A surge protector and polarity protection is a must, in my view. Especially for MBS and all the electronics, and to protect house systems.

I wish I had 300 watts of solar supplement on my roof, but evaluated cost to benefit ratio - and decided I really didn't need it based on how I use the RV. I have to manually hook up my 100W solar suitcase to keep batteries topped off - but thats OK with me, so far. Power conservation habits are key.

Sounds like a great adventure and we are going to do something similar, soon.

Happy Trails.

[RedLdr1]

Originally Posted by FollowTheSun

We are persuaded toward a 2016/17 single slide unit with the diner, closet, and queen bed on the port side. However, I wish to add a few things to the motorhome which I believe will greatly enhance our boondocking comfort.

When you are considering any enhancements keep in mind you only have approximately 1,000 pounds of payload in a "W' MBS floor plan. That 1,000 pounds includes you, your partner, any water, and any supplies... We had a Sunseeker MBS "W" floor plan and it was always border line on being overweight while just being used part time....

There are two routes to consider on power protection, permanently installed in your MH or a removable unit that plugs in to the power pedestal. We currently have a removable 30Amp Surge Guard that plugs in to the power pedestal. If I was full timing I'd go the permanent install route just to take an item off my set up and tear down checklists. Do a Search on Surge Guard and Progressive EMS for more info on which is best for you...

[dukeboone]

Originally Posted by RedLdr1

When you are considering any enhancements keep in mind you only have approximately 1,000 pounds of payload in a "W' MBS floor plan.

My first question was going to be what the weight of a RO system is...

[FollowTheSun]

The system design I am considering includes two stage pre-filtering, a booster pump, and two 150 gpd RO membranes. Total operational system weight is about 30 pounds, 5 pounds of which is already in the coach. This system, when in use, will produces about 13 gallons of fresh water / 22 gallons brine water per hour. The RO system weighs about 15 pounds more than alternative ideas, such as using only a two stage pre-filter. However the RO system weighs about five pounds less than a two-stage system with a portable water softer. Another alternative is to carry bottled water for drinking and cooking, but is idea truly adds a lot of extra weight and seriously impairs otherwise needed storage space.
The plumbing design I hope to install will allow me to bypass the RO membrane when filling with good shore water, and use the membranes when filling with not-so-good water. In my case, I don't see the RO weight as a deciding issue for installing or not. In fact, I think overall, adding RO will reduce my travel/camp weight by eliminating the need for other water, such as bottled.
The deciding issue of me, is determining if there is a safe place to install the components without degrading other useful storage space, while understanding that periodic filter access is necessary. Portable systems are not conducive to this scheme because they must be stored in otherwise valuable storage space.

[FollowTheSun]

Well, we got our 2016 Prism at the end of August. I haven't posted in a while because we've been having too much fun. I finally decided against the RO system because the finished water pH is too low. While RO will always produce safe clean water, and no mineral deposits, the acidic water will likely corrode metal parts over time. I have decided against RO because of the corrosion issue.

[Skyliner]

As a prepper, I'll be installing a RO system that allows me to pull water from lakes and rivers. It'll have a 100 psi 12V pump to ensure adequate pressure against the membrane and will be used to fill my fresh water tank.

The acidity of RO water can easily be neutralized with a very small amount of baking sodar or using PH neutraliing filters....not a big deal.

[JohnF]

Originally Posted by Skyliner

As a prepper, I'll be installing a RO system that allows me to pull water from lakes and rivers. It'll have a 100 psi 12V pump to ensure adequate pressure against the membrane and will be used to fill my fresh water tank.

The acidity of RO water can easily be neutralized with a very small amount of baking sodar or using PH neutraliing filters....not a big deal.

Be sure to add chlorination or uv to kill bacteria.

[FollowTheSun]

Originally Posted by Skyliner

As a prepper, I'll be installing a RO system that allows me to pull water from lakes and rivers. It'll have a 100 psi 12V pump to ensure adequate pressure against the membrane and will be used to fill my fresh water tank.

The acidity of RO water can easily be neutralized with a very small amount of baking sodar or using PH neutraliing filters....not a big deal.

Greeting Skyliner. I still think Reverse Osmosis is great option, especially for the ability to pull and clean water from various sources. An added value, since the RO membrane filters at the molecular level, RO is very effective for removing contaminate such as protozoa, viruses, bacteria which are thousand times larger than than the molecules passed through an RO membrane. Certainly, as you mention, pH is manageable. It's also probably not the issue I make it since nearly everything in an RV water system is plastic. By the way, which methods have you investigated for moving water from a remote source? I thought of using a water hose with a pump at the inlet. The pump at the inlet to pressure the hose rather than draw a vacuum and collapse the hose. The other various ideas I've researched seem to add more extraneous stuff, which I need to reduce or avoid. I have not entirely dismissed the RO idea; I remain interested in learning how folks use and implement this system.

[Skyliner]

My system will be an external system powered powered by either my backup 800 watt 2 stroke generator, solar inverted AC power, or solar provided 12 VDC. I may even consider putting portable solar panels by the water source.

I'll probably use a submersible 12 volt water pump that will feed water to a 25 to 30 gallon storage container, possibly a metal garbage can. The container will allow for crud to settle on the bottom and any floaters to spill over the edge. The RO feed line will installed about 1/3 up from the bottom.

12V Farm & Ranch Solar Powered Submersible DC Water Well Pump 23FT Lift | eBay

From the water tank, I plan on installing a high pressure 12v pump to provide 65psi to the RO system which will have prefilters. Output of RO sytem will go thru a PH filter and them into my fresh water tank. I will add chlorine to my fresh water tank as a precaution and water from the tank will go thru a cartridge filter prior to being pumped into the Rv's plumbing.

Brine will go back to water source or allowed to be absorbed into the ground.

[FollowTheSun]

Originally Posted by Skyliner

My system will be ... ... ... .

Skyliner, thank you for sharing your ideas and plan. You've given it a lot of thought. I like the idea of buffer-storage before bringing the water into the RO unit. That solves issues with volume and pressure differentials between the source pump and the RO pressure pump. Bringing portable electrical power to the pump also gets rid of an extension cord or wires running parallel with the hose.
Another advantage of RO is that contamination-critters (viruses, bacteria and such) cannot pass through the membrane, thus adding chlorine to the purified water is unnecessary. It is, however, important to keep your system clean and protect the membrane from damage or leakage.
I have a 25-foot motorhome, so storage space is premium. Without giving much additional thought, your plan caused me to imagine exchanging the temporary storage with a 5-gallon collapsible water container and filtering the source, to .5 microns, before feeding the temporary storage. This puts clean, not yet purified, water in buffer-storage. That helps protect the membrane and removes prefilter flow restrictions from the RO pump. Prefiltering into buffer-storage also provides for a simplified RO bypass option if needed. A float switch, or sensor, could be added to automatically control the RO pump. A carbon block filter after the sediment filter (before buffer-storage) might be useful to help protect the RO membrane from various chemical contaminates. Other than pH balancing, no other filter or treatment should be necessary after RO. Maybe adding minerals to improve the taste of drinking water, but that could be done with a small cartridge at the faucet.
I agree with your brine management for wild-water. Not sure that “wild-water” is real term, but it seems meaningful here. In fact, during extended boondocking periods, it might be useful to collect the brine for outside uses, such as rinsing down after a hike, prewashing dishes, general outside cleaning around camp, or even spraying to settle dust. However, I think brine management becomes more problematic if using city or park water.
Please keep me posted as your plan develops!

[JohnF]

It is necessary to add chlorine or an ultra violet light to the RO system. Although membranes will likely remove Bactria and Virus they are not 100% reliable. Manufacturers will state that flaws in the production process could cause some pores to be larger than advertised. Also, membranes wear and bacteria can attack them. I've personally seen membranes that were compromised with small tears in them from extended use. You will have no way to monitor these contaminets coming through. A TDS meter will only show the percentage of dissolved solids. And since you are pulling from a known source of water that has a lot of bacteria in it, I would not take the chance.

[dieselguy]

I do submit that you guys have valid concerns with today's water supplies ... it made me reminisce about growing up on a farm in MO drinking, bathing, washing, and cooking with water from a hand dug well minimally lined with pieces of rock with a steel plate covering the top. Dad would throw in a box of chlorine 2-3 times a year and call it good. Here I sit 60 some odd years later typing about it.

[JohnF]

Originally Posted by dieselguy

I do submit that you guys have valid concerns with today's water supplies ... it made me reminisce about growing up on a farm in MO drinking, bathing, washing, and cooking with water from a hand dug well minimally lined with pieces of rock with a steel plate covering the top. Dad would throw in a box of chlorine 2-3 times a year and call it good. Here I sit 60 some odd years later typing about it.

True, but we've learned a little since then. My grandpa would make the same point about seat belts and helmets. I want to die like he did...in his sleep, not screaming in terror like the passengers in his car.

[FollowTheSun]

Regarding the topic about the need for additional sterilization of RO water. I cannot argue either side of that topic, nor do I wish to. What little I know about this subject, I learned from reading other opinions, such as Centers for Disease Control and Prevention. Additionally, there are many expert articles on this subject available on Google Scholar ... some are bit technical and confusing, other not so much. Readers might try several search combinations for "Reverse Osmosis", include words like "bacteria" and such. Read the articles and decide. Keep in mind, however, that many of these articles are written about large commercial systems. Also, it is probably easy to defend water sterilization from a cost perspective, because adding UV or chemical sterilization is really not very expensive. If folks feel necessary to implement additional steps to sterilize their drinking water, they certainly should do so. Even if the water may actually be clean ... the peace-of-mind of knowing you have safe water is itself worth a great deal.

[FollowTheSun]

Originally Posted by dieselguy

I do submit that you guys have valid concerns with today's water supplies ... it made me reminisce about growing up on a farm in MO drinking, bathing, washing, and cooking with water from a hand dug well minimally lined with pieces of rock with a steel plate covering the top. Dad would throw in a box of chlorine 2-3 times a year and call it good. Here I sit 60 some odd years later typing about it.

I got a well like that on my mountain property here in California, and I still drink, bath, wash and cook with it when I visit. I never did the chlorine thing with it yet ... guess I'm lucky. But then, my nearest neighbor is twelve mile away and everybody, including my Crescent-Moon Temple is down hill from the well.