Water purification, LED UV, specifics....

[Hillbilly Heaven]

Problem with carbon filters before UV is that UV light is a focused directed light. They are extremely effective when the TDS is low. High TDS will reflect/refract the UV light and it may not treat as effectively. While carbon filters are great for clarifying water (removing taste and clearing color), microscopic charcoal particles are dissolved in the water.

Tip of the day. You can make the smoothest whiskey from rot gut whiskey by running it thru a charcoal filter. Granted it will not have to color and aged taste but it will be smooth.

 

[Hillbilly Heaven]

Found a better reason to place charcoal filter after the UV. Seems in systems that aren't in constant use bacteria can build up in the charcoal filter and overwhelm the UV system. If you kill the bacteria before the charcoal filter then you will not get growth in the system during periods of no use.

Rainwater Systems and UV and Carbon Filtration

 

[IdaSHO]

Good stuff guys.

[mention]IdaSHO [/mention] I am interested to see what you come up with in this thread. Are you looking at the silver impregnated filters as well to help the filter keep from souring when not flowing?

I havnt nailed down the entire system yet. I'm torn between filtration & purification before the tank, or after, a combination of the two, or both entirely.
Every option has its benefits and drawbacks. And to be fair, most trips will be filled/refilled for the large part from a municipal water source.
But we do have concerns moving forward, and want our bases covered 100% for water needs. Id love to never such water out of a spigot, if I could.

Options... And keep in mind this is for full-time use. Not seasonal, not weekend warrior.

1.
2-stage pre-filter and purify questionable water sources, trust municipal.
Lessens the need/load on the filtration/purification system, and can be a "portable" setup.
Filters would need to be managed, as they are not in use at all times. *Storage issues.
For filling just need power, pump, and appropriate hoses for surface water.
This keep onboard tank 100% potable.

2.
2-stage pre-filter from any source, be it questionable or not. Carbon block and Purify at point of use.
Filters would need to be managed, as they are not in use at all times. *Storage issues.
A bit more complicated as the system may or may not be redundant.
For filling just need power, pump, and appropriate hoses for surface water.
This keep onboard tank filtered, but not purified.

3.
Sediment filter only (single stage) from surface water. Further filtration and purification at point of use.
Simple, and keeps onboard filters in use at all times. No storage issues.
For filling just need power, pump, and appropriate hoses for surface water.
This also has further potential, as I installed a fill-port topside in the camper at the sink.
We could refill from 5-gallon, 1-gallon, whatever jugs as needed. A great option for say... rainwater collection.
Onboard tank is neither filtered nor purified.

 

[Ramdough]

Good stuff guys.



I havnt nailed down the entire system yet. I'm torn between filtration & purification before the tank, or after, a combination of the two, or both entirely.
Every option has its benefits and drawbacks. And to be fair, most trips will be filled/refilled for the large part from a municipal water source.
But we do have concerns moving forward, and want our bases covered 100% for water needs. Id love to never such water out of a spigot, if I could.

Options... And keep in mind this is for full-time use. Not seasonal, not weekend warrior.

1.
2-stage pre-filter and purify questionable water sources, trust municipal.
Lessens the need/load on the filtration/purification system, and can be a "portable" setup.
Filters would need to be managed, as they are not in use at all times. *Storage issues.
For filling just need power, pump, and appropriate hoses for surface water.
This keep onboard tank 100% potable.

2.
2-stage pre-filter from any source, be it questionable or not. Carbon block and Purify at point of use.
Filters would need to be managed, as they are not in use at all times. *Storage issues.
A bit more complicated as the system may or may not be redundant.
For filling just need power, pump, and appropriate hoses for surface water.
This keep onboard tank filtered, but not purified.

3.
Sediment filter only (single stage) from surface water. Further filtration and purification at point of use.
Simple, and keeps onboard filters in use at all times. No storage issues.
For filling just need power, pump, and appropriate hoses for surface water.
This also has further potential, as I installed a fill-port topside in the camper at the sink.
We could refill from 5-gallon, 1-gallon, whatever jugs as needed. A great option for say... rainwater collection.
Onboard tank is neither filtered nor purified.

Here is another option for you….. (this is what I am contemplating)

From your tank, have a pump pick up, through a strainer, then pump. After the pump, have a check valve (for bonus, maybe a double check valve), then have a Tee (or diverter valve) where one side has city water fill and other side is filters/UV. Output of filters have diverted valve(s). Diverted valves either return water to tank(s) through a vacuum break or sends water to usage points. The tanks would have a overflow vent to the shower.

The idea is that if I fill off of the city hose, I push water through the filters into the tanks or straight to the point of use while hooked up. While remote, I can cycle the water in the tanks through the filters and UV to keep the filters and tanks fresh (and not stagnate).

When I use water, it would be filtered and UV cleaned right before use.

I would carry a small pump and hose so I can pump from a water jug or bucket whenever I needed to fill up from a natural source. This would go through the filters before hitting the tank. The remote pump path would have its own strainer and at least a spin down filter/strainer for rough cleaning. If I used a diverter valve from the city hookup, I could use the strainer drain to drain that line out. You could have more filtration, but that would be redundant and take up more space.

I would have a gravity feed to the tank (just in case).

Just what I am considering.


Sent from my iPhone using Tapatalk

 

[IdaSHO]

Interesting plan, but too complicated for me.
Might work for most though.

Ours is very simple as is, being only the sink. No shower. We also dont have provisions for domestic (pressurized) water hookups. We fill with a hose, and move on. Never are we hooked up.

We have two points if water fill, exterior of the camper that is gravity feed to tank, and the same port on the sink, just above the tank itself. They are simple. nylon marine deck ports.

Our sink isnt even a pressurized system. Its an electric foot switch with an electric pump to a simple (no valve) faucet. It flowed when on, but never builds or holds pressure ?

 

[Alloy]

Two things are the same no mater what system is used.
1.) How do you know purification is working?
2.) How do you know the system (tank/lines/pump) is safe?

 

[IdaSHO]

So I did get a response from Jesse @ WaterSafePro

The new LED UV units they are going to use is indeed the PearlAqua Micros.
He also confirmed that it is 100% non-serviceable. Warranty sure, but once the LED fails, you replace the unit.
Though he is confident in the quality of the unit, and I have no reason to doubt the quality.

So that simplifies things, as it is as far as I can tell, the only consumer available, LED based unit on the market.
Feel free to prove me wrong....

So the plan is now to go with the PearlAqua unit for purification, regardless of filtration system
I have requested pricing info, assuming WaterSafePro is willing to sell just the PearlAqua.
Until then, Ill plan on these guys for just the LED purification unit. @ $400

IAQ Pro – Air Quality Monitoring System

Atmocube offers a comprehensive solution for monitoring and managing indoor air quality.

threeuv.com

 

[IdaSHO]

Two things are the same no mater what system is used.
1.) How do you know purification is working?
2.) How do you know the system (tank/lines/pump) is safe?

In short, you don't. There is an indicator on all UV units that it is operating, however. Some also have a "lamp out" indicator.
But ask yourself, how do you know the water coming out of the tap at the house is 100% safe at all times.
You really dont. But you have a certain level of confidence it is.

What I plan on doing is microbiological water testing as the system, whatever I finally devise, is complete.
That's easy enough, as we have a water testing outfit locally that can handle that for cheap.

Once rolling, there are test strips and mail-in lab test kits for all things water quality if I felt the need to verify.
Though done right, a certain level of confidence in the system itself will go a long way.

 

[john61ct]

Every town of a decent size has a professional water testing service.

Ask at county/town hall Health Dept.

 

[Alloy]

In short, you don't. There is an indicator on all UV units that it is operating, however. Some also have a "lamp out" indicator.

The PearlAqua is marketing the Micro is the 1st LED certified to NSF-55, Class B .......certifies ultraviolet water (UV) systems for supplemental bactericidal treatment of disinfected public drinking water.........

We I worked on UV systems. We had to take the systems apart to clean/replace the quartz tubes once a year. The systems were on 24/7. If you use a PearlAqua with water that isn't disinfected stuff will grow inside of it when the UV is off and you can't take it apart to clean the quartz. Sanitizing with chlorine will plug up the carbon block filter.
- How long does a Micro last when use with water that's not disinfected?
- What prevents stuff from growing inside/past the Micro when it is turned off?

This is from the WaterPro manual.
7) Periodically clean onboard water tanks by shock treating with bleach or chlorine.
.....what about the filter system?

After filling our tanks I take the filters out so stuff doens't grow through the filters. When I can't dry the filters (carbon block takes the longest) in the sun green stuff grows on the filter. The paper filters can be sanitized but I can't sanitize the carbon block filter.

 

[LanceMagnum]

I like that PearlAqua unit - I've done some sketching of a water system for my vehicle and it included this:

Arrow 5 UV-LED Water Treatment System | ACUVA

The Arrow 5 is our highest capacity UV-LED water system which can supply multiple waterlines for a variety of applications.

www.acuvatech.com

One feature that's a requirement to keep design and operation simple is that the unit auto-senses when the water is flowing and turns on/off automatically. Looks like the PearlAqua has that feature (as does the acuva).

 

[Joe917]

no affiliation, I have bought from them .

Acuva 1.5 Liter/Min ECO LED UV System - 12V DC

Check out the deal on Acuva 1.5 Liter/Min ECO LED UV System - 12V DC at RV Water Filter Store

www.rvwaterfilterstore.com

 

[IdaSHO]

I like the looks of those units too.

Thanks guys. Ill take a look into them as well.

 

[DirtWhiskey]

I've done some research and made some prototypes of UVC range LED purification. It is still a very young technology. Although the diodes have come substantially down in cost over the last few years, the efficiency of the diodes is crawling up ever so slowly. But we are finally starting to see some really cool systems come about. The primary advantage of LED over mercury vapor lamps is low power consumption, the lack of a need for high voltage ac conversion and attendant conversion losses and robustness. The primary disadvantage is a relatively weak field of radiation. MV tubes have made significant advances too (no degregation over time, more robsutness etc). Also watching Pules Xenon light as a next gen tech. I've had a mercury tube UVC scrubber in my bar's HVAC system for a year in continuos use with no failure. Manufacturer says it will last up to five year of continuous use.

I personally currently see the power saving and size advantages of LED UVC to really shine in remote field use such as hunting and backpacking etc where weight is the critical factor, although that is rapidly changing. For vehicle use, it's assumed you have relatively plenty of power at your disposal and maybe can "afford" the minimal amp draw of the Mercury vapor system in exchange for much cheaper price, and easy/cheap field replacement of the lamps? Not really sure.

I'm also trying to put together a filter scheme for remote truck and marine based use and will be following this thread. One thing I keep thinking of is that chemical treatment in the tank can have it's advantages: longer storage times, sanitized upstream and downstream fittings and slower souring of stored water. Chemicals are easily removed at the point of use with activated/catylized charcoal.

 

[Peter_n_Margaret]

I'm also trying to put together a filter scheme for remote truck and marine based use and will be following this thread. One thing I keep thinking of is that chemical treatment in the tank can have it's advantages: longer storage times, sanitized upstream and downstream fittings and slower souring of stored water. Chemicals are easily removed at the point of use with activated/catylized charcoal.

The OP does not want to hear about chlorine treatment, but it makes a lot of sense, so here goes.
We regularly pick up water from creeks, dams and cattle troughs in the bush in Oz and I did my research about 16 years ago and since then have used a combination of chlorine and filtration, not just in Oz but also in some of the more remote corners of eastern Europe.

First observation is that lovely potable water that you filled your tank with a week ago may not be potable any longer. This is especially true in the tropics where that water might be stored at 30C or maybe higher, the PERFECT environment for those bugs to grow very fast.
But so what? It is not what is in the tank that counts, it is what comes out of the tap. Bugs DO grow in the dark.

Our methodology is this:
1. Treat all water with sodium hypochlorite as the tank is filled. This stuff breaks down quite quickly on its own, especially if the water quality is poor and especially at warmer temperatures, so regular dosing is required to keep the chlorine level up.
2. Filter after the pump and immediately before the tap.
We use a 5um sediment filter (simply to take the large particles out to protect the finer filter), followed by a 0.5um carbon block filter with silver. The carbon block will remove most pathogens, but there should be none anyway f the chlorine is kept up. The carbon block also removes any remaining chlorine.
Simple and effective.

A few "BUTS" to watch.
Fine filters are a great place for nasties to propagate. This is particularly the case if the system is unused for some time. The silver inhibits this growth, but after more than a couple of days of no use, the system should be flushed with 10L of well chlorinated water before consumption. Regular use and regular chlorination is the key to an ongoing safe water supply.
Chlorine concentration is easily checked with readily available test strips, but we tend to work on the basis that if you can not detect the chlorine by nose in unfiltered water, there is probably not enough.
We use 10" filter cartridges. Change them at least annually.
Cheers,
Peter
OKA196 motorhome