Periodic Filtration Bypass to "Cleanse" household plumbing?

[Uellee]

Is there a reasonable benefit to bypassing my GAC filter and softener for a period of time on some regular interval in order to use the chlorine in the city water to "clean" my household plumbing?

I live in southern Louisiana with a large amount of my plumbing exposed to the outside environment. With elevated temperatures for a good percentage of the time and no chlorine present, I am thinking that "stuff" could potentially start to grow inside my pipes after a period of time.

If bypassing is recommended, how often and for how long?

Thank you!

 

[Reach4]

I think so. I am not a pro.

I would put the WH in vacation mode or off. Then drain the WH to get rid of the non-chlorinated water.

How often? I would guess once per year unless you do plumbing work. I would even run that chlorinated water through the softener.

The chlorine levels will be low, so maybe give it many hours of contact time. Maybe run more water in the middle of the treatment to compensate for chlorine that gets used up reacting.

 

[Sponsor]

 

[ditttohead]

Agreed. It is also beneficial for the water heater to run with hard water for a week a year. This will build up a few microns layer of hardness which will not affect efficiency but will provide an additional protective layer on the water heater components. Assuming you have copper, you should be ok. If you have pex, we see lots of interesting growth inside of that piping all the time with or without chlorinated water. Remember, .5 ppm of chlorine is not unusual to see in a municipal supply. This is typically not enough to kill stuff in a plumbing system, it is barely enough to maintain a clean system.

 

[Uellee]

95% of my plumbing is PVC w/ CPVC for hot water

Sounds good except for the chlorinated water straight to the softener. Is this really ok? I am assuming only for a short period of time (maybe one day) because I was under the impression that chlorine isn't very good for the softener media.

When my top load washing machine is filling with unfiltered city water and I open the lid is smells like someone dumped a large amount of bleach in. I know this isn't a very accurate chlorine measurement but it really seems like alot. Maybe I'll see about testing chlorine levels just to see. A little over three years ago the municipal water supply stated that chlorine levels ranged from 1 - 1.45.

Recently I have noticed my water smelling a tad bit stinky on occasion (maybe similar to a light sulfur smell.) My last bypass (no chlorine went into the softener though) was last October for almost a month mostly while we were on vacation.

Thank you for the feedback.

 

[Reach4]

Sounds good except for the chlorinated water straight to the softener. Is this really ok? I am assuming only for a short period of time (maybe one day) because I was under the impression that chlorine isn't very good for the softener media.

You are right, but it is the time plus the chlorine that does the job. You would keep the softener in bypass most of the time, but would give it some time with chlorine, I would think. Here is a quote from page 13 the Fleck 5800 rev B service manual:

Disinfection Of Water Softeners
The materials of construction of the modern water softener
will not support bacterial growth, nor will these materials
contaminate a water supply. During normal use, a softener
may become fouled with organic matter, or in some cases with
bacteria from the water supply. This may result in an off-taste
or odor in the water.
Some softeners may need to be disinfected after installation
and some softeners will require periodic disinfection during
their normal life.
Depending upon the conditions of use, the style of softener, the
type of ion exchanger, and the disinfectant available, a choice
can be made among the following methods.​

It then goes on to describe adding an amount of bleach to the brine tank and doing a regen. I don't have a polished procedure for you. I am just pointing that out that the resin is not that fragile for short periods of chlorine.

A little over three years ago the municipal water supply stated that chlorine levels ranged from 1 - 1.45.

Those numbers are not from samples taken at the end of the line. They want to insert enough chlorine so there will be a residual. They usually want 0.5 ppm or more at the house at the end of the pipes. If your water department uses surface water, there may be times of the year when they add more than usual to deal with algae or something.

If your water department uses chlorine rather than chloromine, you could get some sensitive free chlorine test paper to see if the chlorine is making it out of each faucet, dishwasher, and spigot. If they use chloromine, I am not sure about testing. When I do my well and plumbing sanitizing, I bring the pH down to about 5.5 and I use 200 ppm of chlorine in the well. I want to see 50 ppm at each faucet. Those are about twice what is usually recommended. I like overkill. The softener I keep in bypass most of the time, but give it some chlorine during the period when I am removing chlorine and the recirculating chlorine is down to about 10 ppm.

Will letting the city water through for some number of hours be sufficient to sterilize your piping? I don't know.

 

[ditttohead]

"Sterilization" is a fairly specific definition. In all reality, bacterial "control" is more appropriate. Minimizing and reducing bacterial issues in water is key. Intermittent doses of chlorine through the plumbing is usually adequate to maintain a fairly safe water supply assuming the water treatment components are properly maintained.
Softeners can tolerate a lot of chlorine. It is cumulative damage as stated above. So 1 ppm over the course of a day with 500 gallons of water is 500 ppm of chlorine exposure.