One may discover water softener sizing tools aimed to assist customers in selecting the appropriate sized softener all over the internet.

Unfortunately, the computation for the most majority of these tools does not take water softener efficiency into account.

The end effect is often a choice of softener that seems to be appropriately sized but results in large salt usage (typically more than 2000 pounds per year) rather than a perfectly sized, efficient unit that consumes 300 pounds over the course of the same year.

What causes this to occur? Simply said, a lot of dealers—both online and offline—do not get the idea of softener salt effectiveness and do not take it into account when developing their sizing models.

If you haven’t already, we recommend reading the attached article, which goes into great length on salt efficiency: Accurate Water Softener Capacity Understanding

Why Should I Give Efficiency Any Attention?

The effectiveness of your water softener determines how much salt you need to purchase, transport, and release into the environment.

You may get a softener that never runs out of soft water and uses the least quantity of salt by taking into account the softener’s size and salt efficiency.

This equates to considerable cost savings and simplicity of ownership during the water softener’s lifespan.

How to Size a Water Softener Appropriately

A water softener must be appropriately scaled to meet your individual water quality and use requirements in order to utilize less salt and produce more soft water.

Calculating your “daily softening need” is the first step in correctly sizing your softener.

This is only an estimate of the amount of hardness that your softener will need to remove per day.

The amount of water that has to be softened each day is determined by your water hardness information and water use.

Hardness of Water

The amount of calcium and magnesium dissolved in your water is measured using this.

Wherever a water test is conducted, the results will either be given in mg/L (milligrams per litre) or GPG (grains per gallon).

The industry-standard approach to talk about water hardness is in terms of grains per gallon.

To convert mg/L to GPG, multiply the result by 17.1.

One-hundredth of a pound is equal to one “grain” of water hardness.

Knowing your water’s hardness is crucial if you’re thinking about buying a softener.

A system that is inappropriately sized will arise from estimating this quantity.

Also, the hardness value will be required when programming your softener.

If you’re on your own, you’ll need to test the hardness of the well.

The hardness level of your water may often be obtained from your local water provider if you use city water.

Frequently, you may find their yearly reports online.

The hardness value must be adjusted when there is iron in the water.

Three GPG of hardness must be added to the overall hardness result for every 1.0 ppm or mg/L of iron.

Consumption Of Water

Your household’s water use is the second aspect taken into account when determining the daily softening required.

The most accurate method is to use a water bill that displays total use over a certain time period, often a month.

This information may be used to calculate the typical daily water use for your family.

Simply double the amount of persons living in your house by 75 gallons per day if you don’t have this information.

This will provide a reasonable estimate of daily water usage.

Determine The Daily Softening Need Now.

Add your regular water use to your water hardness (corrected for iron).

Your daily softening need is this number.

Here’s an illustration:

Hardness: 10 grains per gallon.

Daily Water Use: 4 People X 75 Gallons per day = 300 gallons per day.

Daily Softening Requirement = 10 grains per gallon X 300 gallons per day = 3000 grains per day.

The softener will be eliminating 3000 grains per day in the aforementioned case.

Typically, a softener is sized to renew once each week.

Choosing a Softener That Is Right For Your Situation

At this stage, you’ve calculated the daily amount of softening needed using the local climate and your water use.

Typically, water softeners are sized such that they renew once per week or so.

Why only once a week? A once-weekly regeneration achieves a fair compromise between maintaining a fresh resin bed and preventing the valve from suffering undue wear and tear.

The moving components of a water softener valve only move while the softener is renewing.

A water softener regenerates once each week, using roughly 50 gallons of water.

This reduces water use overall.

We need a softener that can soften 21,000 grains of total hardness to regenerate once each week if we take the Daily Softening Requirement of 3000 grains per day and multiply it by 7 days.

What size of water softener, therefore, has a total softening capacity of 21,000 grains? Here is where widely accepted false information from the internet and elsewhere might conceal the actual solution.

There are several water softeners with grain capacities of 24,000, 32,000, 48,000, and 64,000, as can be seen by taking a brief glance online and at many retailers.

When utilizing the aforementioned scenario, where we’re aiming for a total softening capacity of 21,000 grains, it would first seem that the 24,000 grain system would be the best choice.

The 24,000 grain system’s resellers, regrettably, do not mention that it requires 27 pounds of salt to completely renew this system to the 24,000 grain level.

The “24,000” system is better described as “0.75 cubic feet”.

This system has the following resin content.

Even though a user may extract 24,000 grains of capacity from this quantity of resin, doing so requires a significant amount of salt.

Because it includes one cubic foot of softening resin, what most dealers refer to as a “32,000 grain system” is really more appropriately referred to as a “1 cubic foot” system.

The user would need to use 36 pounds of salt every regeneration in order to attain this system’s 32,000 grain capacity! The fact that 20,000 grains of softening capacity may be produced by regenerating a one cubic foot system with 6 pounds of salt is really intriguing.

The savings in salt will rapidly offset the little price premium for the one cubic foot unit compared to the 0.75 cubic foot unit.

Less salt has to be bought, transported, and released into the environment.

A Guide to High-Efficiency Water Softeners

Understanding how much softening capacity is produced by various amounts of resin is crucial for maximizing salt efficiency and eventually saving tons of salt.

Again, the greatest salt efficiencies are used to determine these capacities:

0.75 Cubic Feet of Softener Resin = 15,000 Grains Capacity

1.0 Cubic Feet of Softener Resin = 20,000 Grains Capacity

1.5 Cubic Feet of Softener Resin = 30,000 Grains Capacity

2.0 Cubic Feet of Softener Resin = 40,000 Grains Capacity

3.0 Cubic Feet of Softener Resin = 60,000 Grains Capacity

4.0 Cubic Feet of Softener Resin = 80,000 Grains Capacity

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Written by Bob Matsuoka
Bob Matsuoka is a blogger and founder of RVing Beginner blog. He has been blogging for over five years, writing about his own family’s RV adventures, tips for people who are interested in buying an RV or taking their family on an adventure by RV.