Water Softener Interview Questions & Answers

  1. Question 1. How Does A Water Softener Work?

    Answer :

    Basically, the resin or mineral inside the mineral tank is specially designed to remove “hard” particles of lime and calcium, by a simple ion exchange process. The resin beads inside the softener tank have a different or opposite electrical charge than the dissolved particles of the incoming water. Because of this electrical charge difference, the dissolved particles suspended in your water will cling to the resin beads on contact, thereby ridding the water of these particles, causing the water exiting the unit to be “soft”. The resin has a limit to how much of these hardness particles it can hold, which is why there are many different sizes of softeners and also why regeneration or brining is required.

  2. Question 2. Will A Water Softener Make My Water Safe To Drink?

    Answer :

    No. Your water must be safe to drink before you condition the water with a softener. If you are concerned about the safety of your drinking water, contact your local health department about getting a bacteria test, or full lab analysis on your water.

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  4. Question 3. Why Does Soft Water Feel Slimy Or Slick In The Shower?

    Answer :

    The minerals that make water hard usually contain calcium and magnesium. Calcium and magnesium in water interfere with the cleaning action of soap and detergent. They do this by combining with soap or detergent and forming a scum that does not dissolve in water. Because these minerals react with soap and detergent, they remove the soap and detergent, thereby reducing the effectiveness of these cleaning agents. You can overcome this by adding more soap or detergent. However, the scum that is formed can adhere to what is being washed, making it appear dingy. An automatic water softener connected to water supply pipes removes magnesium and calcium from water and replaces them with a trace amount of sodium. Sodium does not react with soap or detergents. This will reduce the amount of soap you would need to use, and insures it will not remain in or on the item being washed, whether the item is tile, glassware, clothes, skin or hair.

  5. Question 4. When Do The Resins In The Softener Tank Need To Be Changed?

    Answer :

    With the proper pretreatment and maintenance, the average water softener will not need its resins replaced in its lifetime (20 + years). It is impossible to accurately determine the life of resin since so many factors contribute to the degradation of the resin itself. Note: Proper pretreatment can be a simple as a sediment filter or as complex as chemical injection system combined with a multimedia bed, this is determined by having your water tested.

  6. Question 5. I See Ads For “no Salt” Needed Water Conditioners. How Do They Work Without Using Salt?

    Answer :

    There are 2 immediate answers you need to know:

    1. Many dealers will advertise a no salt water conditioner in a misleading way. Any brand of water conditioner can be operated without using salt. This is done by using a salt substitute, potassium chloride. It is generally more expensive compared to regular salt (sodium chloride), and can be difficult to find in some areas. Also, it is generally recommended you increase the salt setting on your control valve by about 10%, when using a salt substitute. This is usually not the method being referred to as a “No Salt” water softener today, but be sure!
    2. NEW TECHNOLOGY SALT FREE WATER SOFTENERS are a recent and reliable alternative that make perfect sense in most applications. There are multiple methods (many products & claims are hype & a waste of money) however, the only reliable one is a process called template assisted crystallization (TAC).

    TAC is a process in which calcium ions in the water are converted to calcium crystals. These crystals now lose any binding or scaling ability and are washed down the drain w/ the rest of the water. Any residential, industrial, or commercial setting will benefit substantially with one of these systems.

    They stop scale build up in the water system and appliances. These systems also eliminate any salt costs and save a considerable amount of space. Additionally, they do not require a control valve and because of this there is no wasted backwash water, and there is very little maintenance.

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  8. Question 6. How Often Do I Need To Add Salt To The Brine Tank?

    Answer :

    It depends on how often you’re system needs to regenerate. The more you’re softener regenerates the more salt you will consume. As for the salt level in the brine tank, you can let the salt get down to the point inside the tank where you can see the water just above the salt. When you see water above the salt, it is time to add more! Generally, you will add salt to your brine tank about every 8 weeks.

  9. Question 7. How Much Salt Should My Softener Use?

    Answer :

    1. An average softener with 1 cu. ft. of resins (30,000 grain, 10 ” x 44 ” tank) should use about 6-8 lbs. per regeneration to achieve an economical 24,000 grain capacity (hardness in grains divided into grains of capacity results in the gallons of water that can be treated before resins is exhausted).
    2. We sell only metered valves with our Watts brand softener packages, since they tend to use less salt than a non-metered unit (i.e. one set to regenerate every so many days with no regards for actual water used).
    3. The national average is 60 lbs. per month, but that can vary depending upon the quantity and the quality of water being treated.
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  11. Question 8. What Kind Of Salt Do You Recommend Using And Do Your Softeners Also Use Potassium Chloride In Place Of Salt?

    Answer :

    We recommend buying salt for your water softener that is very clean; around the 99.5% salt content and up. All softeners can use Potassium Chloride in place of salt. Potassium Chloride tends to melt when it gets wet, sometimes forming a “bridge” inside the salt tank, so we recommend filling the Brine tank only halfway or a bit more when using Potassium Chloride, so you can easily monitor it going down inside the tank after the unit regenerates.

  12. Question 9. My Valve Appears To Be Operating But The Salt Is Not Going Down. What Could Cause This Problem?

    Answer :

    The salt not going down could be due to many different reasons.

    1. Valve is not regenerating due to a mechanical problem.
    2. Salt may be bridged (become solid) above water that is at the bottom of the salt tank.
    3. If you have been using pellet salt for many years you could have a lot of undisclosed residue at the bottom. This residue will not dissolve and also can block water flow in and out of the salt tank.
    4. The valve could be failing to draw the brine solution out and if you have a float shut off in the brine tank, it would be prevent the salt tank from overflowing (which it would do if the float shut off was not there).
    5. The brine refill control could be clogged, prevent water to refill the salt tank.
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  14. Question 10. I Have A Working Water Softener, But I Am Still Getting Iron Staining. Why Is That?

    Answer :

    There are several things that could cause you to still be getting staining:

    1. It is critical that your system never run empty of salt.
    2. It is important that the time of day be kept correct and that no one uses water between 2 a.m. – 3 a.m. when the system is generating. While the system is in regeneration, any water used would be unconditioned (coming straight from the well).
    3. It could be your resin tank is too small to handle all the iron.
    4. It could be you are not regenerating often enough, or using enough salt per regeneration.
    5. It could be that your iron content exceeds the recommended maximum. (1 cu.ft. of resin can effectively remove up to 3 parts per million iron with out additional treatment.)
    6. On rare occasions the iron could be coming from just the hot water tank. If it is more than 20 years old it could be rusting out on the inside, thus putting iron back into the water. This is also true in older homes, again over 20 years old that used galvanized plumbing.
  15. Question 11. I Have A Water Softener, But I Still Have Odor In My Water. Why Is That?

    Answer :

    Water softeners do not remove most taste and odor problems (although they can remove the metallic taste of iron in water).

    1. Odors are typically caused by hydrogen sulfide (“rotten egg smell”) in wells or “bleach” smell in chlorine treated water; both of these causes can be resolved using an activated carbon filter in conjunction with a water softener.
    2. The self-sacrificing rod installed in your hot water heater can sometimes be the cause of your odor in the hot water. Having a qualified plumber replace this rod could solve this problem.
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  17. Question 12. I Have Very Hard Water And High Iron. What Kind Of Softener Do I Need?

    Answer :

    To offer a proper and accurate recommendation for any system(s) needed to correct your water problems, we need current and accurate water test results. Public water suppliers have the information available to you by simply calling them and requesting to know the level of Hardness, Iron and pH of your water. If you have a private well, simply obtain a water test kit from a local hardware store, of you can purchase one of our test kits through a qualified water quality specialist.

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  19. Question 13. How Can I Find Out What Is In My Water…or Where Can I Have My Water Tested?

    Answer :

    If you have public water, simply contact the office where you pay your water bill. They should have current water testing records on file. If you are on a private water system, then contact your county health department to see about having your water tested, or you can buy a Home Water Test kit available from us at this link! Your water test results should show levels of hardness, Iron (what type of Iron you have), pH, Hydrogen Sulfide (for rotten egg odor), Nitrates and Total Dissolved Solids (TDS).

  20. Question 14. How Can I Determine What Kind Of Unit, And What Size I Will Need?

    Answer :

    Filter systems are sized based on a couple of factors:

    1. Type and amount of dissolved mineral present in your water;
    2. Your home’s flow rate, which is typically based on the number of people present in the home.

    For filter systems, this information simply tells us what the fastest rate your water will travel through our units would be, and how much water in gallons per day is being used. Water softeners are sized based on the total hardness of your water, and the number of people in the home. Most all-residential applications have around an average 5 GPM flow rate. Typically, the higher the flow rate of your water going through the unit, the larger the mineral tank will be to handle the larger water flow rate. With a larger tank, the filtering media or resin will be physically deeper thereby permitting the water flowing down through it to be in contact with the media longer. Contact time is important, as the media/resin inside the tank needs to be in contact with your water for a long enough period of time, ensuring all dissolved impurities are removed before it leaves the tank.

  21. Question 15. How Can I Tell What My Flow Rate Is?

    Answer :

    You can get a fairly close idea of your water flow rate by simply running water at full open position through either an outside garden hose faucet or with your bathtub faucet. Example: Turn the faucet on to the full open position… then quickly put the gallon container under the full flow of water. Immediately start timing how many seconds it takes to fill the container all the way up. If it fills the container up in 15 seconds, you simply divide 60 seconds (1 minute)…by 15 seconds (the amount of time it took to fill the container up). The answer is 4, so your flow rate would be very close to 4 GPM! We recommend that you order a unit that would handle at least 4 GPM. It would be over size the unit to ensure you are getting a unit with plenty of GPM flow capacity.

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  23. Question 16. What Kinds Of Iron Could Be In My Water?

    Answer :

    There are basically four types of iron found in water, they are:

    • Oxidized Iron contains red particles easily visible as the water is drawn from the faucet.
    • Soluble or “Clear Water Iron” is very common, and will develop red particles in the water after water is drawn from the faucet, and is exposed to the air for a period of time. The iron particles actually “rust” once they are exposed to air.
    • Colloidal Iron consists of extremely small particles of oxidized iron particles suspended in water. This type iron looks more like cloudy, colored water, instead of being able to actually see small red particles of iron. This type iron will not filter well because of the extremely small particle size. (Chlorination may be required).
    • Bacterial Iron consists of living organisms found in the water and piping of the well and house. You can tell if you have Bacterial Iron by looking in your toilet flush tank, and finding a reddish/green slime buildup. To confirm this, you should take a sample of this slime to your local health department for testing. This kind of iron is the hardest to get rid of. To completely eliminate this form of bacterial iron requires chlorination of the entire water system, starting with the well casing, well pump, pressure tank and the home plumbing system. (Chlorination may be required).
    • Hydrogen Sulfide causes water to have a pungent “rotten egg” odor, and is easily removed using a Manganese Greensand filer.
  24. Question 17. Can The Softener Cause Pressure Loss, If So What Do I Look For, And What Do I Need To Fix It?

    Answer :

    Yes, a softener will cause some pressure loss due to the resistance from the resin bed, but excessive pressure loss can be caused by one or a combination of the following.

    1. On well water, this is usually due to fine sand coming from the well.
    2. On softeners installed in the open sunlight (mostly in Florida), a layer of algae can grow and thick pieces of this growth clog the lower distributor tube screen when they start peeling off the inside of the resin tank.
    3. On chlorinated water supplies, sand can get into the tank from new construction or work on water lines in the area. All of these situations are rare.
    4. The most common cause of pressure loss occurs on chlorinated water. The resin can be damaged by high chlorine levels and turn to mush. This has the same effect as having fine sand at the bottom of the resin tank.

    The solution for all of the above problems is to dump the resin tank, clean and rebed with new resins. One cubic foot of softening resins is enough to properly fill the average residential softener. We can calculate the amount for you, if you provide exact resin tank dimensions.

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  26. Question 18. What Is A Water Softener?

    Answer :

    A water softener reduces the dissolved calcium, magnesium, and to some degree manganese and ferrous iron ion concentration in hard water.

    These “hardness ions” cause three major kinds of undesired effects. Most visibly, metal ions react with soaps and calcium-sensitive detergents, hindering their ability to lather and forming a precipitate—the familiar “bathtub ring”. Presence of “hardness ions” also inhibits the cleaning effect of detergent formulations. Second, calcium and magnesium carbonates tend to precipitate out as hard deposits to the surfaces of pipes and heat exchanger surfaces. This is principally caused by thermal decomposition of bi-carbonate ions but also happens to some extent even in the absence of such ions.

    The resulting build-up of scale can restrict water flow in pipes. In boilers, the deposits act as an insulation that impairs the flow of heat into water, reducing the heating efficiency and allowing the metal boiler components to overheat. In a pressurized system, this can lead to failure of the boiler.[1] Third, the presence of ions in an electrolyte, in this case, hard water, can also lead to galvanic corrosion, in which one metal will preferentially corrode when in contact with another type of metal, when both are in contact with an electrolyte.

    However the sodium (or Potassium) ions released during conventional water softening are much more electrolytic ally active than the Calcium or Magnesium ions that they replace and galvanic corrosion would be expected to be substantially increased by water softening and not decreased. Similarly if any lead plumbing is in use, softened water is likely to be substantially more plumbo-solvent than hard water.



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  28. Question 19. What Is Hydrogen Sulfide?

    Answer :

    Hydrogen sulfide (or hydrogen sulphide) is the chemical compound with the formula H2S. This colorless, toxic and flammable gas is partially responsible for the foul odor of rotten eggs and flatulence.

    It often results from the bacterial break down of sulfates in organic matter in the absence of oxygen, such as in swamps and sewers (anaerobic digestion). It also occurs in volcanic gases, natural gas and some well waters. The odor of H2S is commonly misattributed to elemental sulfur, which is in fact odorless. Hydrogen sulfide has numerous names, some of which are archaic.

  29. Question 20. What Is A Back Washing Filter?

    Answer :

    A backwashing filter is a tank with a specific filtration media filled inside, additional components for structure, and a control valve. The media is typically specific to the elements or components that need to be filtered from the water, such as but not limited to; Arsenic, Nitrates, Iron, Manganese, Chemicals, and Sediments. The water enters the tank, and the elements or components are stopped by the filtration media. The water then travels downwards and travels up through a stem at the bottom of the tank entering the household. During the backwash cleaning cycle, the control valve adjusts the pressure and water flow in the reverse direction, thereby purging the collected elements into a designated drain.

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