Chlorine injection and/or well shocking with whole home pex piping.

[MikeN]

Good day all,
Looking for some advice. I’ve read a lot of threads on here about chlorine injection systems and shocking wells and wanted to make sure I cover my bases before I pull the trigger.

I bought a home that has a well and an aerobic septic system. The whole home is plumbed with PexA (see photo from attic) and I have PVC from the well house to just outside the house, where it’s unioned to Pex. The home was built in 2009 and sat from 2012-2022 pretty much vacant. We had the water tested twice and fortunately don’t have coliform or worse. However, we were getting bad orange staining in the toilets with an organic (not sulfur) odor and clogged shower heads. Also, I replaced the valve at the Pex/PVC union and found orange film in the PVC and black film in the Pex.

I figured we needed a treatment system so I sent the water out for testing and got the attached results. Every salesman has said we need a whole home RO due to the chlorides and TDS, but frankly I can’t drop $15k on a system. For now I wanted to take care of the iron eating bacteria, hardness, and hopefully some of the sediment. I figured I’d start by having a company install a sediment filter, chlorine injection system, carbon backwash, softener, and POU RO.

As I read on here and other sites, I started getting concerned that I may inadvertently damage the Pex piping if I use chlorine to shock the well or if there is any residue chlorine post injection and carbon filter. The Pex in my attic looks to have a chlorine resistance rating of 1, so now I’m kinda at a loss and wanted to reach out for some help.

Thanks in advance for any assistance and sorry for the long post!

 

[Valveman]

Moving to plumbing where you may get more help.

 

[Sponsor]

 

[JohnCT]

Good day all,
Looking for some advice. I’ve read a lot of threads on here about chlorine injection systems and shocking wells and wanted to make sure I cover my bases before I pull the trigger.

I bought a home that has a well and an aerobic septic system. The whole home is plumbed with PexA (see photo from attic) and I have PVC from the well house to just outside the house, where it’s unioned to Pex. The home was built in 2009 and sat from 2012-2022 pretty much vacant. We had the water tested twice and fortunately don’t have coliform or worse. However, we were getting bad orange staining in the toilets with an organic (not sulfur) odor and clogged shower heads. Also, I replaced the valve at the Pex/PVC union and found orange film in the PVC and black film in the Pex.

I figured we needed a treatment system so I sent the water out for testing and got the attached results. Every salesman has said we need a whole home RO due to the chlorides and TDS, but frankly I can’t drop $15k on a system. For now I wanted to take care of the iron eating bacteria, hardness, and hopefully some of the sediment. I figured I’d start by having a company install a sediment filter, chlorine injection system, carbon backwash, softener, and POU RO.

As I read on here and other sites, I started getting concerned that I may inadvertently damage the Pex piping if I use chlorine to shock the well or if there is any residue chlorine post injection and carbon filter. The Pex in my attic looks to have a chlorine resistance rating of 1, so now I’m kinda at a loss and wanted to reach out for some help.

Thanks in advance for any assistance and sorry for the long post!

Your pics are small so I can't read the pipe - what brand of PEX A is that? From the pics, the pipe looks like copper - so is that an opaque/white pipe that's turned that color??

If the house was vacant that long with stagnant water in it for ten years, I don't know if I'd ever trust any plastic pipe under those conditions. While I think it's possible to chemically flush and sterilize copper, I don't know if the PEX can ever be cleaned thoroughly of those deposits.

If the house is one level with an open basement, I'd replumb the house and probably go with copper and a filter system.

If that isn't feasible and the plan is to salvage the PEX, I'd contact the PEX manufacturer and see if they can add any insight to what you've got going there.

John

 

[Reach4]

You would like a settling tank between the chlorine injection and the backwashing carbon tank. That should have a blowoff valve that lets you easily drain the settled sediment.

There are two major types of chlorine injection:
1. When the pump runs the chlorine is injected. This must inject before the pressure tank.
2. Proportional injection needs a proportional pump that is told by a proportional flow sensor how much chlorine to inject. Injection is after the pressure tank This costs more.


Long-term exposure to chlorine is much harder on plastic than a few hours during sanitizing.

Your plan sounds good to me.

https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up.

 

[GReynolds929]

Your pics are small so I can't read the pipe - what brand of PEX A is that? From the pics, the pipe looks like copper - so is that an opaque/white pipe that's turned that color??

If the house was vacant that long with stagnant water in it for ten years, I don't know if I'd ever trust any plastic pipe under those conditions. While I think it's possible to chemically flush and sterilize copper, I don't know if the PEX can ever be cleaned thoroughly of those deposits.

If the house is one level with an open basement, I'd replumb the house and probably go with copper and a filter system.

If that isn't feasible and the plan is to salvage the PEX, I'd contact the PEX manufacturer and see if they can add any insight to what you've got going there.

John

It's Rehau

 

[Fitter30]

This has a chart for how much chlorine to use

Guidelines for Disinfecting Dug and Drilled Wells - Environment and Climate Change

Groundwater, by nature, is bacterially pure. The presence of total and faecal coliform in well water is evidence that pollution has occurred in the well. These contaminants cannot be detected by taste or visual inspection, making them a hidden hazard. Bacterial contaminants are common to the...

www.gov.nl.ca

 

[Reach4]

Nice article. However the tables only serves as a starting point, because the bleach gets consumed doing its job. So I recommend measuring the chlorine concentration of the recirculating water.

I end up adding more.

pH has a lot to do with the activity of chlorine bleach.