Fresh Water Tank Sanitation

[freestoneangler]

We just got back from our first trip with the new TT.  Upon hooking up to the RV sites pressurized water system, we noted a rotten egg smell coming from the faucets.  There was a lawn sprinkler being fed from that same frost free bib and it had no odor, so I came to the conclusion that the water in the on board tank and left in the lines since we purchased the unit a month or so ago had fouled. The smell went away after a short while of running all the faucets, but we chose not to drink the water until we came back and could run a shock chlorine/clean cycle. 

My question to the forum is how do you maintain your potable water tank?  From what I've gathered on-line, It seems most use the chlorine shock method and do not run that solution through the hot water heater. How frequently do you perform this the chlorine shock of other treatment method?   Do you drain the entire system after doing the treatment by opening all the faucets and low point drain?  Is there a general rule about how many days water can be in the system and still be safe?

I started looking into the options for adding water treatment units (other threads), but haven't yet decided which one I want.  But even with one of these, residual, stagnant water in lines and cartridge filters may be susceptible.

Thanks

[Kirk W]

15 hours ago, freestoneangler said:

My question to the forum is how do you maintain your potable water tank?  From what I've gathered on-line, It seems most use the chlorine shock method and do not run that solution through the hot water heater.

1

Here is a link to instructions on sanitizing an RV water system. It is important to sanitize the water heater as well as all other parts of the system as there are algae's that grow in hot water and some of them are the most likely to cause the bad odors. If the system sits with water in it for long periods unused, the chlorine of the water will slowly degrade to a point that it does no good at all. It is recommended that an RV system is sanitized annually, although the more that it is used with city water, the less likely you are to have the problem. One downside to using a quality water filter is that most take out any chlorine or other germicides so if exposed to air you can develop an algae growth in the tank or water heater. 

[LindaH]

15 hours ago, freestoneangler said:

From what I've gathered on-line, It seems most use the chlorine shock method and do not run that solution through the hot water heater.

We ALWAYS run the chlorine mixture through the water heater! 

Our method was to fill the fresh water tank with the appropriate amount of chlorine based on our total fresh water capacity, including the water heater (and filling up the tank with fresh water, of course).  Then we drained the water heater and filled it up with the chlorine water from the fresh water tank.  After running the chlorine mixture through all the faucets and letting it sit for at least 3 hours, we'd drain everything, including the water heater and fill the fresh water tank and water heater back up with fresh water.

Some people do a rinse with either vinegar or baking soda, but we never minded the little bit of chlorine smell that remained and it quickly dissipated.  (We now have an instant water heater, so we simply run the chlorine mixture through it by turning on all the hot water faucets.) 

[jblscooper]

You said you had hooked up to the water supply and got the smell. If so, you are not using your water tank for water. unless you have the pump on, water from the tank is not being supplied to your system. The other suggestions about the tand are spot on.

[Flying Finn]

Freestone,

After you sanitize your system consider adding a product called "Purogene".  It can be purchased online at rvwaterfilterstore.com.  Follow the directions and you should be good to go.

Finn

[LFDR3116]

We also run the chlorine solution thru our water heater by turning on the hot water and letting it run until we smell chlorine in the hot water.  All sinks and shower, hot & cold.    Then rinse is done thru all, both hot and cold until no more smell.  Tank is filled and drained, rinsed and drained a couple of time.  We also do the water hose we are using.  Have seen one cut apart that was all black inside with mold, so sanitize that too.

[freestoneangler]

Great info all - thanks.  After doing the shock treatment, and leaving the system as completely drained as possible, how long should one expect that to last?  For instance, if I run this sequence today and we don't use the trailer for few weeks, should it be OK?  Also, if we sanitize the potable tank and only use campground water, is simply draining the lines by opening the hot and cold faucets sufficient from any residual in the lines from going bad (again for maybe 2-3 week periods)?

[JimK]

If your water smells, chances are the source is the hot water tank.  At least that was my situation.  Typically I have just sanitized the cold portion of the system.  After two years of not being used and the hot water tank sitting with the plug removed, I got a strong odor from the HW tank.  Bleach cured the issue but it took a couple of hours and numerous flushes. 

[JimK]

You don't need to leave the system empty after sanitizing.  In fact I would be concerned about that.  Filling it completely will cover the surfaces with treated water.  It is my understanding that the system should remain ok indefinitely if used.  I have sanitized mine once a year even when in use.  If the water sits stagnant for more than a month or so, at a minimum, I would drain the system and refill.  I use a Britta filter and drink the camper water so I am extra cautious.  I treated my system several weeks ago and am not leaving until next week.  I am going to hit the main tank with a quarter dose of bleach, pull water through the cold side and then drain and replace.  It takes me almost no work and just a little time to sanitize my CW.  My HW drain is fussy and tends to leak unless I cover the drain plug threads with just enough Teflon tape so I will leave it alone this time. 

[2gypsies]

We've never had the problem probably because our water system was in constant use.  However, we have heard of folks with the rotten egg smell and it was always traced to the hot water tank.

[Ron]

I sanitize ours once a year also but I've always wondered why this was really necessary.  When we lived in a stick house we never thought to sanitize the house plumbing or the water heater even if we had been gone for several weeks.  It's not clear to me why there's any real difference.  If you use untreated well water I can understand the need.

[Barbaraok]

Ron,

We've had our rig since 2005.  Have never done the shock or any other treatment besides using municipal water.  Start of travel, dump water (we have a 100 gallon fresh water tank so it takes a while) then fill completely (water out the overfill) then dump again after letting it sit all day, drawing some of the water through the pump, then dump again and fill 1/2 full for traveling.  Add to it as necessary from municipal sources.  Dave has a PhD in biochemistry, I've got a MS in Chem Eng and have worked with water treatment facilities.  Yes I'm picky about the sources I use to fill rinse and fill the tank, never do that in the southwest (water far to alkaline for us) wait until we get to reliable sources on the coast, always check for residual chlorine smell in early am.   This works for us.

[freestoneangler]

Shock treatment in progress... I even thought to include the outside shower faucet.  It's interesting how many recipes regarding concentration are out on the web.  Common concentrated household bleach is only about 5.25% - which likely explains most of the varying mixes and wait to drain times.  I went with Kirk's as it matched several others I found.  From the responses, it sounds like the full-timers have little issue as their constantly flushing and probably often with water sources containing chlorine.  This drill adds a milk jug and a good size funnel to the storage bay for repeating out on the road if necessary. 

[Kirk W]

5 hours ago, freestoneangler said:

Also, if we sanitize the potable tank and only use campground water, is simply draining the lines by opening the hot and cold faucets sufficient from any residual in the lines from going bad (again for maybe 2-3 week periods)?

I don't drain ours for short periods but generally, leave water in it all of the time when not on the road with it, but there is no absolute prevention for algae problems. Some feel it better to leave things dry and neither is 100% wrong but I go to the more convenient way. I do drain the fresh water tank and refill it just before leaving.

4 hours ago, Ron said:

I sanitize ours once a year also but I've always wondered why this was really necessary

 

3 hours ago, Barbaraok said:

We've had our rig since 2005.  Have never done the shock or any other treatment besides using municipal w

Sanitizing a water system or even the kitchen counters and sink are only preventative measures and no guarantee. It is rather like wearing a seat belt, or gloves when dumping the sanitary tanks. We wear them as a risk reducer but they don't guarantee that you won't be harmed and that same thing is true of sanitizing anything. But even when we drive wearing a seat belt for many years and never are in an accident, most of us continue to wear one every time we drive. Is that wrong?

Only 1 time in our more than 35 years of RV travels have we ever had problems with algae and that one was when on well water at a host site in a campground where the fresh water hose was out in direct sun. After discovering the green algae in our hose and flecks in the ice cubes as well as in the faucet aerators, I treated it completely to get rid of it and I added pipe insulation to our hose to block the sun exposure as I learned from reading about it that direct sun enhances algae growth. There is another algae that grow in water heaters and causes the odor you had. It is not a rare thing for the water an rural RV parks, or both federal and state parks to be well water that is not chlorinated. It is tested for purity and safe use, but that don't prevent algae which can come from the air. 

[Ray,IN]

Think this through; you said you hooked up to city water, then noticed the odor, which disappeared after a few minutes.

This is no different than a city water line to a house that sits unused for a few weeks, then the city turns the water back on. The house owner(you perhaps) opens faucets upon their return, which removes any odor, sediment, etc. Nothing special is added to the city water line, they just let the following chlorinated water clear the line, just as you did when you ran water through your lines for a few minutes.

Your onboard fresh water storage tank OTOH, can stagnate over several months, with no way to replenish Chlorine without draining the entire water system and dosing the storage tank again. How to Sanitize your fresh water system explains the procedure in detail, I use the second method beginning at 2nd half of that page, which I perform once each spring.

This is completely different than disinfecting drinking water that you feel is not safe to put in your mouth.

 

[Vladimir]

I have had the same problem when not using the water system for a period of time. 

See this Forest Service tech note on using Vitamin C to neutralize the chlorine.

https://www.fs.fed.us/t-d/pubs/html/05231301/05231301.html

BTW....this i my MINORITY opinion. I NEVER drink the water from my fresh water tanks. Long story, but I don't want to take the chance when it is so easy to buy clean drinking water at stores or use filtered water for drinking.

AND I do drink untreated water from streams when hiking!!!

But I don't trust the fresh water storage tanks on my RV. We had a Forest Engineer in the Forest Service that always got sick when he went camping. He finally tracked it down to his tanks and came to the conclusion that it was impossible to keep the tanks pure.