Kinetico - Flush Neutralizer

At one point I was given a few options to address the need to change our filter so often. This option was cheapest…surprise, I chose it!

BACKGROUND

We are on a well and so I was convinced we needed a water treatment system. I should discuss this in a different post, but suffice it to say that having water treatment comes with some maintenance. Here are the steps I follow to routinely purge the NU1100 tank.

I have more history below, but I wanted these steps near the top.

STEPS

When you do this, do the filter first and use the water pressure from this to clean the filter.

1. Turn Softener valve to RED (no water into the house)
2. Connect hose to spigot between tanks
3. Run hose outside towards pond
4. Turn on spigot full blast
5. Let run for 8 minutes (so as not to deplete the entire well)
6. Turn spigot off and disconnect hose
7. Turn Softener valve back to GREEN
8. Clean up

COMPLETED

• 2019-04-14
• 2018-10-14
• 2018-04-14
• 2018-10-20
• …

HISTORY

When I noted my displeasure in (a) having to change the filter so often and (b) how dirty it was every time I changed it, I got a great response which I will paste here (as a side note, Gene has always provided great information):

Possibility #1: The water from your well was clear to the eye but did have a small amount of dissolved iron in it which I measured at 0.25 mg/L. It is possible that this has increased or changed and the water is no longer clear and has ferric iron in it. This can be checked by running water at the well into a white bucket to see. Wait for the pump to come on to do the evaluation. If the water now has color, this ferric iron oxide will not be stopped by the neutralizer since the neutralizer is Upflow in flowpath. It will move through to the filter and load it up.

Possibility #2 (most likely) - The small amount of dissolved iron, which may vary a bit, is slowly reacting with the calcite (CaCO3) in the neutralizer tank and due to the extra oxygen there, this iron is being converted to ferric iron (Fe3+) which forms insoluble particles. Since the NU1100 is Upflow these particles form near the bottom of the tank as the water enters and they must move out of the tank by traveling upwards through the heavy calcite media. The problem is the particles are small and dense, and since the flow rates in the house are not large, they tend to agglomerate into clots inside the calcite bed. After a while, or under higher flow conditions, the rusty clots eventually move to the top of the bed and then go overhead and get trapped in the filter. The fact that you have to change the filter often is a sign that the calcite bed has gotten loaded up.

Solution Options:

1. We should have installed a flushing spigot on the outlet side of the NU1100 tank BEFORE the filter inlet. I would hook up a long hose to this to reach outside and then turn on full blast. Monitor in a white bucket as you run it and I bet you will see good water at first and then as the iron oxide clots free up, they will come flying out of there. The water will likely be brown and awful. Sometimes you can run this until the water clears back up. This will force out most of the built-up rust in the NU1100 tank. If successful, then the filter life should go back to a normal frequency until you need to do it again.

2. The other option is to add an electric backwashing valve to the neutralizer system to make it a Downflow system. This valve would thread into the top of the tank and the flowpath through the NU system would be downflow instead of upflow. This means the bed will be packed and act as a filter as well as a neutralizer. Because the bed is packed, instead of fluidized (with upflow), the rust particles will get trapped in the bed as they form, and must be backwashed out with the electric valve. This system would then have a discharge line like the softener. We normally have them backwash every other night at 2 AM. This option is an automatic way to keep the calcite cleaner when iron oxidation is happening. The cost to make this conversion would be around $550-600.

When I first tested the water I found the iron levels low enough that I did not think this would be an issue. However, we have seen this before on occasion when we have measured iron at low levels - it is a cumulative problem that occurs over time.

[return to top of page]