What size softener do I have? Determining the size of your existing water softener. March 12, 2018 14:01

Many of the new water softener sales inquiries we get are from customers looking to replace an old water softener. Our sales process involves steps where we help our customers figure out precisely what size of new softener will get the job done for them. In the case of customers who are replacing an old and broken softener, they often just want the same size they had before.

But determining what size they currently have can be harder than it seems it should be. Here are two different methods you can use to determine what size softener you presently have. We're going to assume that you can physically get to the 'softening' tank. This is the tank that has the softener control valve on top. Some 'all in one' softeners where the softening tank sits inside of the salt tank make it really hard to get at the softening tank.

The way to figure out the size of softener you've got, is all about getting the dimensions of that softening tank. Here are two ways to do that:

The Sticker Method:

Many water softeners have a sticker somewhere on the softening tank. The sticker should have a large-print 4-digit number on it.  An example is 1048. Here's what this means:

water softener tank dimensions size

The first two-digit number is the tank diameter in inches. The second number is the tank height in inches.

Measuring the tank:

If there's no sticker, then you'll be stuck measuring. First you'll need to measure the height of the tank. Measure from the floor to the neck of thank. This is the point where the tank meets the control valve. Record this measurement in inches.

The next measurement is the tank diameter. Diameter is the distance across the tank. It can be hard to measure this for a round object but this measurement is critical in determining the size softener you've got. A difference of 1" is the difference between softeners of one size another.

If you're finding it too hard to accurately measure the diameter, you can instead use a piece of string to measure the circumference (distance around) the tank. Take that number and divide it by 3.14 to get the diameter.

Once the height and diameter are known, you can use the following chart to determine the cubic feet of resin that your softener is built with. All measurements are in inches:

 Tank Diameter Tank Height Cubic Feet Resin Grain Capacity*
8" 44" 0.75 24,000
9" 48" 1.0 32,000
10" 48" 1.25 40,000
10" 54" 1.5 48,000
12" 48" 1.75 56,000
12" 52" 2.0 64,000
13" 52" 2.5 80,000
14" 65" 3.0 96,000

 * The "Grain Capacity" of the softener is the name it may have been sold under, and doesn't necessarily reflect the softening capacity of the system.