first time sanitize fresh water tanks

[rvshrinker]

About to sanitize my tanks for the first time (we haven’t drunk the water from the tanks, we just use for cleaning and bathing and so on,, but we are about to go on a long trip with many dry days so we’ll need the water for cooking and drinking).

I understand the basic principles - fill with properly diluted bleach solution, let sit, run through all the faucets and fixtures, fill with fresh water, drain through fixtures, repeat until no bleach smell — but have some questions about the details.

1. What do I do about the water heater? Do I turn on the electric and propane water heater switches to make sure any bleach water is cycling through those as well? How long do I let those run to ensure proper sanitation? Do I need to drain that first somehow?

2. Is it necessary to ‘drive around’ with full bleachy tanks to ensure bleach solution is splashing up and coating all the surfaces?

3. When filling the tank, do I truly fill the fresh water inlet until it is overflowing (as I’ve read)? Previously i’ve read not to do that to avoid damaging the plumbing.

I have pool liquid chlorine which is stronger than regular household bleach so I will use the correct amount of active ingredient. when I mix my solution.

thank you

[Varmintmist]

Boon Docker wrote:

dedmiston wrote:
When I was a kid, I had the first drink of water after my dad had earlier sanitized the tank in our TC. I vomited quite a bit that first morning of our trip until my own personal sanitation was complete.

I've never forgotten that and never sanitized the fresh tanks in any of our RVs. If the water has sat too long, I drain it and refill it.

100% vomit free.

Your Dad should have drain and flushed the tank before you took your first drink. :B

Or maybe that is how he found out that he needed to flush the tanks 🙂

I did it in the spring, and will again. Fill with a cup of chlorine in it, let it sit for a day or two, drain and refill. If there is a little chlorine taste left, it is still better than city water. Might do it this weekend.

As a thought... Does anyone who rv's mostly without hookups ever just refill the tank at the end of the trip, add chlorine and let it sit until the next time you run the trailer?

[rvshrinker]

Grit dog wrote:
Chlorine disappears basically 4 ways. Time, UV / air exposure, chemical neutralization or dilution.
Since the system is not really exposed to open air and sunlight, you can either wait, use dechlorination tabs (sodium sulphate, vitamin C , etc) or dilute it.
When disinfecting pipelines I use dechlorination tabs.
Small quantity like a Camper water tank, just fill and drain a couple times.

FWIW, google is your friend here. You can learn a lot about this with a little research.

i figure it was 50 ppm when sanitizing, i drained it all out, so if there’s less than a gallon left in my 80 gallon tank it would be diluted to 100:1, which is 0.5 ppm, probably about the same as municipal water. so i guess i’m done.

i guess if it tastes too much like chlorine in a week or so i’ll drain it one more time.

[Boon_Docker]

dedmiston wrote:
When I was a kid, I had the first drink of water after my dad had earlier sanitized the tank in our TC. I vomited quite a bit that first morning of our trip until my own personal sanitation was complete.

I've never forgotten that and never sanitized the fresh tanks in any of our RVs. If the water has sat too long, I drain it and refill it.

100% vomit free.

Your Dad should have drain and flushed the tank before you took your first drink. :B

[dedmiston]

When I was a kid, I had the first drink of water after my dad had earlier sanitized the tank in our TC. I vomited quite a bit that first morning of our trip until my own personal sanitation was complete.

I've never forgotten that and never sanitized the fresh tanks in any of our RVs. If the water has sat too long, I drain it and refill it.

100% vomit free.

[Grit_dog]

Chlorine disappears basically 4 ways. Time, UV / air exposure, chemical neutralization or dilution.
Since the system is not really exposed to open air and sunlight, you can either wait, use dechlorination tabs (sodium sulphate, vitamin C , etc) or dilute it.
When disinfecting pipelines I use dechlorination tabs.
Small quantity like a Camper water tank, just fill and drain a couple times.

FWIW, google is your friend here. You can learn a lot about this with a little research.

[rvshrinker]

when i drain the water and water heater, and then refill - do i refill completely full, then drain all that water out, including the water heater? onlline i see people talk about just draining the water until the bleach smell is gone, but wouldnt some of the bleachy residue still be mixed in with my fresh water?

[Grit_dog]

^What he said. Stop overthinking it.
This is literally as simple as filling and draining the water system along with adding a little chlorine when filling it.
In the Time between my last 2 posts, while you were posting, you could have done it twice including flushing.

[dieseltruckdriv]

You don't NEED to open the low point drains for sanitizing, just run water through every faucet until you smell the bleach solution. The low point drains just speed things up a little.

I let my anode rod sit dry every winter, but with my water it needs to be replaced every 2-3 years anyway.

[rvshrinker]

i’m going to call the dealer and see if he can tell me for sure, as I can’t see any way to open those valves from the inside. They come up through the bathroom sink cabinet.

I did drain my whole system including the hot water heater tank. The anode rod is slightly pitted, a bit more at the neck, but no rust and seems good enough to put back in (it’s 2.5 years old). I’m reading conflicting info about whether the anode rod should be kept wet or dry when not in use; manufacturer seems to suggest draining the tank when not in use for extended time, others say don’t let it dry out.

[Grit_dog]

RVshrinker, I'll assume you've never used or drained your water system based on the questions and over complicating this procedure.
1. Find the water heater drain (anode). Check, you found that
2. Find your freshwater tank drain valve.
3. Starting with relatively empty FW tank.
4. Drain hot water heater
5. Fill freshwater tank full, add bleach while filling. 4-8 oz of 5% household chlorine for a 50 gal tank. More won't hurt, within reason, but will take longer and or more flushing to neutralize though. If your using more concentrated chlorine, adjust accordingly.
6. Run some water through lines, filling hot water tank. Top off FW tank of you feel it necessary to get it more "bleachyyy".
7. Drain everything incl hot water tank.
8. Let sit for chlorine to neutralize, or add any number of neutralizing bases, or simply fill and flush once or twice. Bottom line, residual will smell for a few days or longer unless you actively neutralize or flush repeatedly. But the smell isn't hurting anything unless you want to start drinking the water in short order. Then it just smells is all.

I've disinfected many potable water sources from small municipal water lines to large distribution pipelines and 10s of million gallon storage facilities and reservoirs.
It's not rocket science. Get diluted chlorine contact on all surfaces. Remove chlorine to residual levels before drinking. It's literally that easy and you can't really screw it up.

[bigorange]

Boon Docker wrote:

Be sure to open a hot faucet before removing the water heater plug. There could be a lot of pressure there if you don't open a faucet first.

You can also open the pressure relief valve on the water heater. Been there, done that and took a blast of hot water to the gut from a pressurized tank.

Also, if your tank has a little on/off toggle switch for electric on the tank itself, make sure that’s turned off before draining so you don’t burn out your element.

[Boon_Docker]

I use 8 oz of household bleach for my 30 gallon tank.

[Vintage465]

OK, so I've not sanitized mine...........ever and I think it's time. What is the ratio of gallons of water Vs. chlorine or peroxide?

[Lynnmor]

Boon Docker wrote:

Also no need to open release valve on water heater, just open a hot faucet when draining the tank.

That varies, my trailer won't drain unless the T&P valve is open. Perhaps it might if I wait a week or two. A check valve in the outlet for a one valve winterizing system probably makes the difference.