# DIY Water Softener System

Hard water has a high concentration of minerals, and of these calcium salts are the most troublesome. But there is a solution coming in form of a cheap diy water softener system built with the well-known 555 IC. Actually the price of this diy system is so low that even if this doesn’t work you won’t be upset.

The working principle of the water softener is based on a theory from 1930 which states that an electromagnetic or electric field causes small crystals of calcium carbonate in the water to join together to form larger crystals.

One of the methods to obtain a strong magnetic field is to put a powerful magnet (2.5 gauss) near the water pipe. The second method is the electronic one. Studying a water filter purchased from stores we found that it produces a frequency of about 15 kHz at an amplitude of 15V.

## Schematic of the Water Softener Circuit

cheap diy water softener system circuit schematic

UPDATE: If the water pipe is metallic then connect the open ends of the coils to the pipe, or if it is made of plastic connect each open end with a conductive wire (copper).

Extension: water softener power indicator

The values of the coils are not known, but my guess is L1 has 9 turns and L2 has 7 turns. Actually you should consider this circuit as a theoretical one.

Therefore this water softener system uses one 555 IC to obtain a rectangular signal that is applied to the water pipe by wrapping two coils with one open ending around it. The coils must have good isolation. Make sure to power the water softener from a isolated power supply because in some areas the water pipes are connected to ground.

• Richard Chapman

RE: “Apparently, the coils behave as a capacitor” or antenna.

This circuit does not create a magnetic field: it creates an electric field.

From other research I did, it seems that the length of the inductor wires are what is important, not the number of turns. Therefore, 77 turns on a 1″ (2.57cm)od pipe = 20’2″ and 75 turns = 19’7½”. Number of turns will vary for larger or smaller pipe.

• Richard Chapman

Also from the article:

The coils are open ended. Apparently, the coils behave as a capacitor.

The article also states that the coils are insulated to prevent electrical contact with the pipes. So it is apparent a metal water pipe was used.

Whether plastic pipes can be used can easily be tested using the water-hardness-testing method described in the article. If plastic pipe doesn’t work, a section of copper pipe can easily be fitted into a plastic plumbing system.

• Richard Chapman

RE: “Apparently, the coils behave as a capacitor” or antenna.

This circuit does not create a magnetic field: it creates an electric field.

From other research I did, it seems that the length of the inductor wires are what is important, not the number of turns. Therefore, 77 turns on a 1″ (2.57cm)od pipe = 20’2″ and 75 turns = 19’7½”. Number of turns will vary for larger or smaller pipe.

• C.Mitra

Richard Chapman
Your wise and confident comments show that you have really studied this circuit very deeply, and you must have done a lot of practical experiments with it. The figures 20’2″ and 19’71/2″ seems a bit too much to digest! What happens if you increase the lengths by say half an inch? Or decrease by one inch? You must have tabulated all the results with the corresponding change in the deposition of calcium and magnesium molecules, most probably taking the help of chemical analysis? I would be grateful to you if you publish all the data for the benefit of the readers.
As of my opinion, this circuit is crap!
Is there ANYONE OUT THERE, who has ACTUALLY made the circuit and found out that it REALLY WORKS? Please come forward.
Thanks everybody.

• Richard Chapman

From what I see of photos of commercial units, number of coils on either side are equal. 6 or 7 turns.

A sediment filter will probably remove calcium carbonate crystals. Sediment filters are available down to 5 microns. (I would use the readily available and cheap 20 micron filter followed by the more expensive 5 micron filter. Hopefully the 20 micron filter will remove most of the larger calcium carbonate crystals.)

circuit notes: (page 3)
4.Number of turns of inductor wire at positive output = 77
5.Number of turns of inductor wire at the ground = 75
6.The gauge of the wire used for inductor = SWG32

• Chinmoy Mitra

The article which your link points to is the best example of tomfoolery and bullshit I have ever seen. Anybody in his senses will loose his mental balance if he seriously reads it.
The author has cut and pasted a lot of electronic jargon in the article to impress the gullible public.

The introduction is in itself an example of utter nonsense….quote “Water is an odourless, tasteless and colourless or transparent liquid. It has a bluish tint, which may be detected in layers of considerable depth only”. Do you consider this an intorduction to a scientific paper?

Further, he announces a couple of very important characteristics of water….”Under standard atmospheric pressure (760 mm Hg) the freezing point of water is 0 degrees Centigrade and its boiling point is 100 degrees centigrade. Water attains its maximum density at a temperature of 4 degrees and thence expands upon freezing (Nelkon, 1994).” This, I think, is taught in primary school. He has even gone to the extent of giving a reference to some “Nelcon, 1994” to make it all look so authentic!

Even the circuit schematic is incomplete and illegible. A cursory glance at the article may give the feeling it is a scientific paper, but in depth study shows it is simply crap! It is beyond my comprehension how such an article got printed in a scientific journal.

• Girdhar Gupta

Treated water has to be stored in a storage tank so as the Calcium build up settles there and the tank is cleaned periodically.
The softened water is used from the Tank.

• P. Marian

Just a small update on the circuit: connect both ends of the coil to the water pipe if it is metallic or with use a copper wire if the pipe is made of plastic or other non-conductive materials.

• beachmezz

I do not believe this circuit can work as the coil is not a complete circuit therefore no magnetic field. Ii coil is an antenna the resulting field would be microscopic and unable to penetrate the water pipe

• Gary

I remember the product and the items on sale in the late 60’s and 70’s A box fitted with three A cells and two terminals linked together with a 15 inch length of wire and it pulsed a 100 Hz signal at 15 ma through the wire that was supposed to be wrapped around the riseing main in the house “even if it was Iron”! and align all the salt molecule ‘domains’ tests in the lab using titrated solutions from 1 part in 100,00,000 to 1 in 100 and field strengths varying from nil to intense from a 100 turn coil and passing a current from 100 uA to 80 Amps, all at frequency’s from 100 hz to 5 Khz (the max frequency that the shaker table amplifier was stable into the coil) and over two terms of collage with a group of students only gave a positive answer with a >0.50% saturation level.
The little circuit above looks like it runs at 2.9 Khz into a very small coil that’s open circuit even if it was a complete coil gives a current around 60 ma
I think it has as much chance of working as a chocolate kettle!

• aldoemilio

this project http://www.researchinventy.com/papers/v1i3/I013039042.pdf has some results from tests on apparently similar prototype.

• C.Mitra

Very interesting explanation from wildman. But “magnetic alignment” of minerals in water? I have got an interesting idea for an experiment. Dissolve any salt, can be calcium carbonate or sodium chloride or whatever, in water to make a saturated solution. Place this water in a glass trough or maybe a test tube. Apply a very strong magnetic filed to this solution to “magnetically Align” all the molecules. With the magnetic field in place, subject the solution to very low temperature in a refrigerator until the solution freezes. Since all the magnetically aligned molecules are aligned in one direction, now this solid frozen solution should behave like a permanent magnet! Magnetic Ice! Brilliant.
Now for your comment ” provided the current is NOT reversed”, the circuit above is basically an oscillator producing pulses of current which reverse in direction about 15000 times every second. So your theory does not work in the present situation.
Please correct me if I am wrong.

• dhiraj

You sir are too modest to call ullekhit on this circuit so let me do it I think people in support of this facade have never been exposed to even high school physics

• wildman

I can not comment of the strength or viability of the circuit.

However, regarding the way these devices function, it is my understanding that they do not ‘remove’ minerals from the water, but rather influences the magnetic alignment of the molecules in such a way that they seek to follow one another with the flow of water…

You’ve probably seen this experiment in elementary school science class…

Lay several stick type magnets on small individual pieces of wood, with the north and south end of the magnet slightly overhanging the edge of the wood and float them on water. Once you have a number of magnets floating, drag one near enough another for the magnetic fields to react… eventually you can have a string of magnets lined up in a train like fashion…

(Yes I realize they can cluster if you allow that and the above was just to help give a visual, there is more to the equation which explained below.)

While this example is a bit over simplified the component which I have yet to explain is that provided the current is NOT reversed, the electromagnetic field which is wrapped around the pipe will always maintain the same North/South (+/-) orientation. In theory what will happen as the force of the water flows through the pipe the mineral molecules will seek to align and flow as if strings/trains in the water.

The theory behind these devices has never been ‘disproved’ which is why these type devices can still be sold in the USA. However, they can NOT be called water softeners, but are labeled as scale removers.

Looking for the latest from TI?