Forum Discussion

rvshrinker's avatar
rvshrinker
Explorer III
May 22, 2020

first time sanitize fresh water tanks

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
  • alright, I will ignore the bypass water heater. that was exactly my question. back to draining the water heater, how do I do that? I’ve never winterized (we have a mild climate and I just run the heater if it’s going to get close to freezing).

    see above, i did find a short stubby 1” PVC coming down vertically from what looks like the low point of my trailer bottom. I do not see any overflow near the water inlet. Do you think that is it?
  • Terrible advice on a couple things in that video. Two things in that video that I would not follow.
    1. Bypassing the hot water tank. You want to sanatize the water heater.
    2. Use winterizing system to suck in the bleach. That system will not add the bleach to the fresh water tank.

    Now to answer your questions.
    1.Do not bypass the water heater.
    3.No, the overflow has nothing to do with the water heater.
    4.No, a lot the trailers have the overflow tube right by the water inlet.
  • Fisherman wrote:

    Somehow I don't believe you understand the concept of plumbing. Activating the cold water heater by turning it on either electric or propane does nothing to circulate the water in the water heater tank. That's done by ensuring the water heater bypass taps are off and you end up filling the tank by running the pump. Open both hot and cold taps at all your sinks/showers to get the javex/water mix through them.



    I i watched this video and now have more questions:

    https://youtu.be/jEepug8N-aE

    1. It says to use the bypass feature on the water heater, just like you said. Where would that be located? I see the panel to my suburban water heater, located on the outside of my trailer. Do I remove that panel to access the valves?

    2. if i use the bypass, but water is still going into the water heater tank, what is being bypassed?

    3. if I fill the system to overflow, is the water heater tank also filled to full to ensure all surfaces are sanitized?

    4. The video says that I will know the system is full when the overflow under the trailer starts dripping. Is this true for all models? I see a short piece of 1” PVC coming down vertically from the bottom of my trailer and assume that is it?

    5. so if I leave the water heater off, and bypass as per above, is there a small amount of contaminated water on the other side of the gates? When I run hot water through all the faucets, I’ll be drawing from the hot water tank, even though the water is cold?
  • I have a suggestion for ya: instead of bleach, use peroxide. It is more expensive, but works as well, and does not leave any nasty, hard to remove aftertastes or smells.

    You don't say how big your fresh water tank is, so I can only tell you what I do each spring. Into an otherwise empty 30 gallon fresh water tank on my TT, I pour a whole quart of 3% peroxide. Then I fill the tank, and when it is finally full, I use the onboard pump to fill the entire system, including the water heater. Then I let it sit for at least 24 hours. Finally, drain the fresh tank and the water heater, hook up shore water and flush the system. Done.
  • Just make sure you get all the bleach water out.....you don't want the wife to yell at you when she gets a sip of water out of the faucet. Been there, done that.
  • 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?
    Somehow I don't believe you understand the concept of plumbing. Activating the cold water heater by turning it on either electric or propane does nothing to circulate the water in the water heater tank. That's done by ensuring the water heater bypass taps are off and you end up filling the tank by running the pump. Open both hot and cold taps at all your sinks/showers to get the javex/water mix through them.

    Driving around will help the action.
  • 1. No need to turn on water heater, but do drain it first before sanitizing. Then drain it again when finished sanitizing.
    2.Not necessary to drive around.
    3.Yes, fill to overflowing.