Drain water between trips

RDP · 05-31-2020, 05:31 PM

I have 30 days until my next RV trailer camping trip, should I drain the water tank, water heater and open water line drain valves? What is the best practice when the trailer sits more than 30 days between trips. I don't want to have to re-sanitize the water system. Thanks!

Morich · 05-31-2020, 07:45 PM

It's going to be a judgement call with no firm answer, in my view.
Part of my thinking involves experience in water treatment combined with keeping fish tanks. Believe it or not those two relate as they both involve chlorine or chloramine for water treatment and that is part of the question on draining tanks. Water is treated to manage much of the bacteria but not all that is in water to drink but the chlorine treatment gasses off somewhat quickly and water begins to let bacteria grow. Chloramine does but much slower. So the thought is that we can get away with leaving water in the tank but how long depends on several points that will vary a bunch. How hot and how long and which treatment is used as well as how we plan to use the water.
If it's warm out and more than a week, I don't like the idea of drinking the water but okay for showers, etc. One way to get much longer out of the water is to add a bit of bleach to bump the chlorine content back up before using. Also adding new water to a half full tank gets new treatment chemicals in. I do not drain the hot water between trips over a summer on not to frequent use. Heating the water will kill most of the bacteria which might/ might not have grown.
Each person will have their own comfort level so this is certainly not a firm rule of any sort!

Goodspike · 05-31-2020, 08:49 PM

I don't drink from the water system, and don't drink from the hot water system even at home. That said, it isn't that hard to drain the main tank, so why not? The water heater tank is also not that difficult to drain, but more of an issue on refill. So how about a compromise? Drain the main but not the hot?

Wyatt · 05-31-2020, 10:10 PM

I like Richard’s answer, but to add to that our local water company said six months is fine.

Morich · 06-01-2020, 03:03 PM

Water is an interesting subject and it takes lots of different tunrs when we look closer.
I normally do drain the fresh water tank if I'm not expecting to go out in a montho r so but part of that is how easy it is for me to drain and refill. If I were in a situation where draingor refilling was a problem, I might delay it longer. So personal situation changes the answer.
But one reason for thinking about the bacteria that make multiply in the tank is the way most don't fully drain and may leave an inch or so in the bottom of the tank as well as water in the lines if we don't go full bore and blow them out. I might guess that myt current Rv, setting where I store it. might have as much a five gallons left as the drain is not on the bottom but the side of the tank.
Just a glass of water left out for a few weeks will get pretty nasty as the airflow lets the treatment gas off and the remaining bacteria which is not killed in treatment is left to multiply. Even bottled water has a certain amount of bacteria and is labeled with an expiration date so a glass full gets bad much quicker. So what might I expect to find in the RV tank where there is limited airflow, lots of moisture and certainly a nice temperature for bacteria?
In a water main, the situation is somewhat different as there is a certain amount of circulation with new treated water and being contained in the pipe where there is limited space for the treatment to gas off.
I consider heating the water to be kind of a wash on safety as it does stay warm which "could" promote more bacteria growth as we don't heat the water hot enough nor long enough to sterilise it well, but on the other hand, we use far more hot water than cold in the RV as we use limited cold but do showers and dish washing in hot. So the larger amount of use adds more new water with new treatment in it to the hot water tank where it has the dwell time to do the job.
But it is all a moving, changing, question with lots of different answers.

Goodspike · 06-01-2020, 03:45 PM

Quote:

Originally Posted by Morich

.
I consider heating the water to be kind of a wash on safety as it does stay warm which "could" promote more bacteria growth as we don't heat the water hot enough nor long enough to sterilise it well, but on the other hand, we use far more hot water than cold in the RV as we use limited cold but do showers and dish washing in hot. So the larger amount of use adds more new water with new treatment in it to the hot water tank where it has the dwell time to do the job.
But it is all a moving, changing, question with lots of different answers.

I had not thought about this before, but the rather high temperature that RV hot water tanks are set to could help. While it's so hot it's unsafe for scalding, it could be hot enough to kill off some things.

I can't find a link, but some modern home systems are set for a higher temperture, about 140-145 if I remember right, to kill off some bacteria, and then use a mixer valve to get the at the faucet temperature down to 120.

Anyway, I typically turn off the water heater before it gets to full temp, but maybe the first time out I'll leave it on to take advantage of the high heat.

DavidM · 06-01-2020, 05:33 PM

I wouldn't bother to drain the hot water tanks and other plumbing for a few months in between camping trips. I leave maybe 5 gallons in the water tank for use on the road. Any more is just extra weight. I fill the tanks when I get to the campsite.

David

TJFogelberg · 06-02-2020, 01:44 AM

We don't drink from the system, so we only drain it 1X a year before putting her away for the winter. Most grocery stores and WM have reverse osmosis water dispensers. The water tastes better than most tap water and has toxins removed. It's a small inconvenience but I have been doing it for 30 years and swear it improves my health. At home and the office, I have Culligan delivered which is great tasting and pure and comes in hard plastic which is better than some of the plastics used for common water bottles. Too much hassle to drain the system inbetween trips.

**macnut** · 06-02-2020, 05:23 PM

Adding Purogene is a safe and easy way to store water. It’s just an ounce per 30 gallons. I have used it for years and my tank is pristine.

https://www.amazon.com/dp/B07B68XLCG..._O6T1EbEE4P5AQ[/URL]

Topsail · 06-03-2020, 07:00 AM

Quote:

Originally Posted by macnut

Adding Purogene is a safe and easy way to store water. It’s just an ounce per 30 gallons. I have used it for years and my tank is pristine.

https://www.amazon.com/dp/B07B68XLCG..._O6T1EbEE4P5AQ[/URL]

Thanks. I may try this suggestion.

RDP · 06-04-2020, 03:26 PM

macnut, do you add the Purogene to a full tank of water?

**macnut** · 06-04-2020, 11:29 PM

Yes, I usually add when I am filling the tank.

Morich · 06-05-2020, 09:07 AM

Does this also require the crystals mentioned as an "activator"?

**macnut** · 06-05-2020, 09:31 PM

No, the crystals (citric acid) are just if you want to use it for annual servicing. For normal use, just 1oz per 30 gallons. We have used it for 8 years in our RV fresh water, which we use for everything....drinking, ice cubes, coffee, shower, etc. As a side benefit, the water always tastes good.

pmglidden · 06-07-2020, 09:25 AM

A couple notes here:

Viruses and bacteria require water temps of 180f for 5 minutes before they start getting killed off. The hot water heater will not affect them.

If you are filling with city water, it is normally treated enough that sitting 30days won’t allow harmful growth If you are filling from untreated water though you’ll need to think that through a bit more. If something is present in the tank it can grow in well water without issue.

Wyatt · 06-07-2020, 12:18 PM

Hot water kills germs, though it has to be very hot
According to WHO, temperatures of 140°F to 150°F are enough to kill most viruses, and boiling water makes it safe from pathogens like bacteria, viruses, and protozoa. Trivedi recommends a temperature of 160°F or greater when heating water or food products, to kill off bacteria like Legionella, a common bacteria found in water.

https://www.insider.com/what-temperature-kills-germs

Goodspike · 06-07-2020, 12:24 PM

Quote:

Originally Posted by pmglidden

If you are filling with city water, it is normally treated enough that sitting 30days won’t allow harmful growth If you are filling from untreated water though you’ll need to think that through a bit more. If something is present in the tank it can grow in well water without issue.

Also factor in you may have some water in the tank that already has stuff living in it, and if it's a significant amount of remaining water that will dilute the chlorine and its effectiveness.

Think of it as a gallon jug instead. You could easily fill such a jug with city water and be okay 30 days later. But if the jug has 2" of water in the bottom that has been sitting for months and you then filled the jug full I wouldn't want to drink out of it even right away.

SaltLife · 06-07-2020, 05:57 PM

I'm in the, drain the main tank camp and nothing else... . Because that's what I do ..

RLCASC · 06-07-2020, 06:23 PM

I know most of this Thread is about water quality, but Another consideration is to drain the WH after each trip to prevent calcium buildup or attacking of the anode rod.

Ttowntoehead · 06-08-2020, 07:08 AM

We never drink water from our rv tank. We quit because finding good water to drink on the road is sketchy. And bad water goes worse quickly in summer. We just use it for bathroom and kitchen duty while traveling and then empty when arriving for a lengthy stay. We try not to use too much bottled water and have a zero water filter that really helps.