Desinfection of the fresh water tank.

[GeorgeRa]

I need to disinfected my fresh water tank and with shore water connection only I couldn’t just pour bleach into the water tank. So, I got a simple inline filter to help me.

Filled the clear container with bleach, placed the filter in line with water hose, clicked open fill and pressure relieve solenoid valves to fill the system, did this a couple of times with a full drain of water tank and the water heater tank, done.

[booster]

No gravity fill on your van?

[GeorgeRa]

No, missing in action. It was planned but found that the original route for the gravity fill allowed maximum size of about 3/8” hose, it would be useless.

Pressure fill was easy, but to prevent overpressure in the tank not so. I have a 0.5 PSI pressure relief ¾” check valve in series with solenoid. To fill I open both solenoid valves and the tank is filled in a few minutes, overfill flow let me know when is done. Life of building a DIY prototype, but, there is always a solution, just more time and money.

[SteveJ]

Can just filling/flushing with good ol' chlorinated city water do the sanitation? Logic would say yes as the chlorine is placed in the water to kill bacteria, right??

[GeorgeRa]

Yes, but I left water in the fresh tank for almost 3 months. So extra chlorine is a good precaution.

[avanti]

I would not trust city water as a disinfectant solution, even without the 3-month issue. As I understand it, the effectiveness of disinfection is some function of both chlorine concentration and time. Maybe city water sitting days would disinfect the part of the system it was sitting in, but there are other places that would not be in constant contact with the water for a long enough period. The upper sections of the tank comes to mind. It is important to overfill the system when sanitizing, because you want to force water out of the top vent tube, and also any overflow path. This is often overlooked, and I have seen some very moldy vent tubes.

[Bud]

"The upper sections of the tank comes to mind. It is important to overfill the system when sanitizing, because you want to force water out of the top vent tube, and also any overflow path."

And then I go for a very short drive before turning on the chlorine water for the pipes.....

Bud

[JohnnyFry]

Even though I depend on my UV Sterilizer to supply the taps with clean water, I do periodically dose the main tank with Clorox. There is the possibility of mold build up in the tank which could plug the filter if it went on too far. Although it would be rendered inert by the UV I wouldn't be wild about drinking it.

[MsNomer]

Mold would not necessarily be rendered inert by the UV. UV can't kill what it can't "see," so only the surface layer of the mold would be affected.

[GeorgeRa]

The best way to prevent algae to grow in a water tank is to block all light.

[JohnnyFry]

Very true, it certainly would not affect mold growing in the tank but as it passed by the light in the water stream it would bekilled. Of course, this assumes that there is no mold growing in the water lines after the UV light. That is why I use Clorox regularly. My major concern is contaminated supply water. I am sure that campgrounds are not required to test for fecal colliform on a regular basis.