Carbon backwash system with chlorine question

[pdc]

I have a whole house carbon backwash filtration system. The media uses a chlorine solution to backwash. I'm new to this system and am trying to figure out how it functions. During the backwash cycle the chlorine solution is drawn into the carbon tank. The chlorine tank is 16 gallons and about half of it is drawn in for the backwash. I'm thinking when finished the solution used is expelled to waste and the chlorine tank is replenished with just new water effectively reducing the concentration by half. Is this correct? If so how do you know how much chlorine to add to keep the correct concentration? When refilling, the chlorine tank is regulated by a float valve much like a toilet.

 

[Reach4]

What you have is not common. I have a backwashing filter that uses a very special carbon, and it removes H2S and iron. It backwashes every 3 days, and it draws in some of the chlorine solution. It has a 15 gallon solution tank that does not refill on its own. Every 36 days I need to add a gallon of chlorine bleach, and top up with water. (I actually do it every 5 weeks for easier scheduling).

Do you have any documentation? There may be a dealer sticker, and they could tell you what you have. Can you contact the previous owner and ask about the system?

Is this for your own well? If so, do you have a lab water test of your raw water?

If it is city water, does the water department use chloramines to sanitize the water rather than chlorine?

What do you think the purpose is?

 

[Sponsor]

 

[pdc]

This is my well. Sounds like yours is similar as mine also cycles every 3 days. It uses centaur carbon and is used for removing hydrogen sulfi

de. I don't have lab results.

 

[Reach4]

What makes you think your tank contains Centaur Carbon???
Looking at your picture, I don't match your description. I have marked up your picture a bit.

M appears to be a water softener tank with controller M. Q looks like a brine tank for the softener.

N is a tank containing something. K appears to be an air pump, but I am not sure. That hose at H... is that an air intake, or was it dipped into some solution? Tank N does not appear to have a controller, and if so, it would not do something every 3 days.

Somebody else may have a better idea of what you have. Your system is not like mine. My Centaur Carbon tank has a 15 gallon solution tank, and it has its own controller atop the tank.

I don't have lab results.

I like kit 90 from http://www.karlabs.com/watertestkit/

 

[pdc]

M is the backwash filter containing the centaur carbon. Q is the 15 gallon tank containing the chlorine. D is an aeration tank that the air pump services. R is the pressure tank and to the left, not shown is the softener. L is the controller for the carbon tank.

 

[Reach4]

Got it.

My media tank is 10x54 inches. It holds 1.5 cuft of Centaur Carbon. The media is said to last maybe 7 years or so. This is not GAC. I bought my system in November 2012. My tank uses 5 GPM backwash with a 10 that 10 inch tank.

Is your tank M 12x52 or what? That would correspond to 2 cubic ft of media. A 12 inch tank should use 1.44 times as much backwash as a 10 inch tank, which comes to 7.07 gallons to match up to my 5 gpm... but 7 is probably close enough.

For the programming of mine, BF=4 meaning that solution is drawn for 4 minutes. It is drawing at the rate of 0.3125 GPM.
My BF=0, so that it does not refill the water.
Your controller is a mechanical controller, so adjustments are going to be different. If you can, you will want to minimize brine fill (where water is added). That could let you refill your solution tank after several regenerations. If your unit continues as it is (without making adjustments) every 3 days (each regen) will want to add about 14 ounces of bleach. This is simply scaling from what I do. It is possible that you could come up with something that would save that frequent chore. Perhaps you could put a pool chlorinating tablets into the tank and let that do the job. Then you could go a long time between visits to the tank. I am not a pro.

I set my electronic calendar to remind me to refill every 5 weeks. Every third time, there is some left in the tank, but I still add my gallon of bleach, and top off with water. If you could top off with soft water, that would be better. I am actually using 121 ounces of 8.25 bleach instead of 128 ounces of 5.5% bleach, because that is how the bleach is sold. It is a little stronger than the original recommendation, but I think it is close enough.

 

[ditttohead]

Wow, that aeration tank has some miles on it.

The air pump design is not as common as it used to be. Considerable advances in medias, system designs etc have almost eliminated this type of equipment.

The centaur carbon/Chlorine regen design is fairly effective in some applications. Again, newer designs have really limited this design as companies need a more consistent performing design. The chlorine/centaur design works great sometimes, other times it is highly ineffective. It is a little to hit/miss to recommend as a generic design.

Typical chlorine regen designs will incorporate an electronic valve, not the mechanical like you have. The mechanical valve cant be regulated for brine draw times. This design would more often be used with a chlorine tablet rather than liquid bleach. The refill would be a few gallons of water.

Not the best design but likely effective.

Time for a water test. Kar LAbs is excellent, NTL Labs Well kit is also a good choice.