How do you sanitize your fresh-water tank and lines?

OP, whatever you do to conserve water, to disinfect your water system, you need to wet all surfaces with the bleach solution, and keep it wet for about 4 hours. (Bleach doesn't kill bacteria instantly, it takes a certain amount of time.) That includes all surfaces of the fresh water tank, the water heater, and every water line in the RV, including the outside shower. I do this once a year, every spring when de-winterizing the RV.

Boon Docker wrote:
Wow, lots of useless answers on how to use the least amount of water.

To the OP, try this:

Fill fresh water tank with 15 gallons of water and 1/2 cup household bleach.
Tow your trailer around for about 10-15 mins to slosh the bleach mixture around.
Bypass the water heater, then pump the mixture through the hot and cold water lines.
Leave mixture sit for a few hours then drain the tank and fully fill with water. Run the fresh water through each hot and cold line for 15-20 secs. You are done.

Works fine for me.

Do you not feel the water heater needs disinfecting too? Some water sits in it all winter.

Boon Docker wrote:
Wow, lots of useless answers on how to use the least amount of water.

To the OP, try this:

Fill fresh water tank with 15 gallons of water and 1/2 cup household bleach.
Tow your trailer around for about 10-15 mins to slosh the bleach mixture around.
Bypass the water heater, then pump the mixture through the hot and cold water lines.
Leave mixture sit for a few hours then drain the tank and fully fill with water. Run the fresh water through each hot and cold line for 15-20 secs. You are done.

Works fine for me.

This is the answer. Include the low point drains.

TechWriter wrote:

3 tons wrote:
Never done it in 14 years - I can visually see up close both ends of the fresh tank and it is still spotless

My eyes aren't as good as yours. I can't see bacteria.

3 tons wrote:
BTW, cith water has chlorine in it and apparently this is enough to do the job…

All campgrounds don't have chlorinated water supplies.

OP, I think most folks, including myself, sanitize our RV water tanks periodically. Once or twice a year for me.

I use either bleach or Purogene. Bleach is cheap, but caustic as hell. Purogene is pricey but easy on people.

For a typical 50ppm bleach sanitize, it's 1/4 cup bleach per 15 gal of holding tank capacity and let sit for 4 hours. For a stronger (100 ppm) concentration, it's 1/2 cup bleach per 15 gal and let it sit 1 hour.

Finally, you'll probably get some interesting rationale from folks who never sanitize their water tanks like . . .

- "I haven't gotten sick yet." (Also a popular excuse for smokers.)

- "I used to drink out of a water hose when I was a kid" (What this has to do with tank sanitation still escapes me.)

Okay Fair enough (though from my perspective, a bit of myopic hyperbole :R…), but we fill the tank before each outing with pre-chlorinated city water, and we drink only bottled R.O. (reverse osmosis) processed water, and if you care to think about it (whether at home or not…) chlorine is a very effective and economical water disinfectant which has benefited the entire world (especially, due to economics, the third world), but chlorine is also a known well established carcinogen (though this fact is mostly dismissed - possibly a mere case of ignorance is bliss??…), whereby the bulk of one’s exposure occurs through directly the derma (skin) when bathing… So in my view, rather than paint with such a broad brush (facts matter, eh?), in my judgement each person need be aware of this risk and (based on information) chose whatever the best informed option of their own choice - FWIW, this may contrary to conventional wholesale wisdom…

I would also add here that the chlorine in city water tends to evaporate from a storage tank in about 30 or so minutes, we see the same thing happening in swimming pools as well…

Upon re-read, Techwriter also wrote: “My eyes aren't as good as yours. I can't see bacteria.”…..

Well, this migh surprise some but there’s about 2 billion bacteria within the human body’s interstitial fluids alone, all of which are in circulation and are beneficial (by design, ingesting toxins)… Point being (ego aside - lol) is that we are all just another part of this vast biosphere…

Thanks in advance ‘for tolerating’ this opposing point of view…

3 tons

I use chlorine granules for pools. It takes very little and it does not have the "icky" taste that household bleach has. So, you don't have to rinse the tank after dumping the bleach-infused tank.

Add chlorine granules to some water and mix. Dump into the tank. Fill the tank partway - drive and slosh (or fill all the way and leave sit for a couple hours). Run through all the faucets until empty.

Add water for your trip as needed.

I do this when I first get an RV. After that, I only do it if I've left water in the tank for several months or I filled my tank from an unfamiliar water source.

Funny thing is I use to not sanitize and now I do. We got some bad water a few years ago.

I use 1 Step No Rinse sanitizer once a year now. The same thing I use for my brewing equipment.

Dissolve 2lbs in a 5 gallon jug. Add that to my 40gal tank, fill and let it sit overnight. Drain, refill and flush the lines.

Wow, lots of useless answers on how to use the least amount of water.

To the OP, try this:

Fill fresh water tank with 15 gallons of water and 1/2 cup household bleach.
Tow your trailer around for about 10-15 mins to slosh the bleach mixture around.
Bypass the water heater, then pump the mixture through the hot and cold water lines.
Leave mixture sit for a few hours then drain the tank and fully fill with water. Run the fresh water through each hot and cold line for 15-20 secs. You are done.

Works fine for me.

hedgehopper wrote:
The instructions that came with our rig use a lot of water. In scarce-water Colorado we do not want to use more than necessary. How do you do yours?

Lol, what?
If 100 or 200 gallons pegs your environmental consciousness meter, I’d suggest trading for a Prius and a tent.
In the interest of actually sanitizing your tank, your tank you need to fill it full with water with whatever chemical you choose and then run it through the lines as well. And then it’ll take a tank or 2 to flush. Although residual chlorine dissipates over time so you can use less flushing if you don’t need to use the water tank for a period of time after sanitizing it.

You’re gonna use 2-3 tank full of water bout no matter how you slice it.

I used the bleach method each spring. I carried separate drinking water. I used the water with bleach for toilet and doing the dishes. After refilling the tank water was okay to drink.

I did when we were newbees but quit after a year or two. haven't sanitized the water system for 30+ years. to each their own.