[thedoc]

I’ve been told a magnetic field can dissolve lime scale in water pipes. Is this true and how does it work since the pipes and I believe the lime scale aren’t ferrous and not affected by a magnet.

Asked by Tony, Dereham, Norfolk

                                          Hear this Question on our Podcast

[thedoc]

We put this to Dr Hugh Hunt, from Cambridge University's Engineering department:
I am Hugh Hunt from Cambridge University Engineering Department.  Well, there are lots of manufacturer’s websites that claim that if you put magnets on your water pipes then that prevents limescale build up on the element of your emission heater.  Well it’s obviously in manufacturer’s interest to make these claims but lets suppose that in the last year a manufacturer has sold a thousand of these devices and they get one letter which says how fantastic it is, another ten letters that say that doesn’t work.  Well they can give ten refunds.  They have still made quite a lot of money and they can publish that one nice letter and I guess that not be what we are seeing on the websites but now that’s being a bit mean but I am a bit puzzled that there aren’t any quoted referred scientific publications out of the mainstream literature. 
Surely if there was something really scientific going on here it would be well and truly understood.  So I just wonder.  Now there are few possible candidate theories all to do with magneto hydrodynamics and water memory and things to do with nucleation and so on, you can read all about these.  Where does that leave us?  Well I think if you have found that one of these devices works for you, well it doesn’t do any harm so you may as well carry on using it.  But if you find that it doesn’t work then perhaps there’s no surprise in that. 

[wolfekeeper]

I was told this too, by a plumber that was trying to sell me such a magnet for my very, very hard water.

I thought about it, laughed at him.

I later checked, and organizations like Which have failed to show any effect of these kinds of magnets.

I suppose a sufficiently strong magnet could in principle change the crystal structure if the field extended right through the boiler (since water is slightly magnetic), but the ones that they try to sell you that clip onto a pipe, before the boiler, it just can't work- the water would be disordered by Brownian motion within a few microns of leaving the field.

[chris]

I am amazed that these devices continue to be sold because I honestly cannot believe that they work. I can only think that perhaps some sort of changing magnetic field could induce a current in the pipe material perhaps electrolysing the water or the metal on the inside the pipe - but then again exactly what this would do I've no idea...

Chris

[Chris]

Wow, water memory got mentioned. I thought this was supposed to be a science show. Boo!

[Victor]

I am an Electrical Engineer, BE, and a magnetic system design specialist. We have designed systems since 1991 when our shareholder was the CSIRO. The science of the transformation is not easily understood. The fact is that we have done trials in agriculture and mining. In mining applications we have engineers not believing the results but they have no choice but to buy the units because they clear the pipes. The deal was they pay only if it removes the scale. Within a few months they bought a second unit for a second line because it worked. Removed years of scale build up in a 6 inch underground coal mine pipeline at Mandalong in the Hunter NSW Australia. The fact is the magnetic field must be strong enough and the magnetic profile must be right. The laws of physics used are clear they are related to Lorentz theory. It is all about charged particles moving in magnetic fields. Just like an electric generator. Just like the old style TV or computer screen. Crystals just have to form differently. The difference between strings and balls coming together. The naivety of the so call intellectuals who are not willing to believe their own eyes. Reminds me of when the first positron was discovered. It appeared in an experiment with electrons which are negative. The positron positive charge was considered an error until some more open minded scientist realised that a positron may exist. Magnetic water conditioning works in most situations but it has some limitations controlled by the water chemistry. Certain element combinations are not as effected as others. That is true with all chemistry as not all chemicals react with every known element. There is a limited range of cases for their reactions. The truth about magnetic systems test results is that when scientist do tests on the treated water they are not doing correct tests. They do tests that test for certain reactions that would normally imply a certain substance present not the effect of the magnetic field. So the science being used to contradict the magnetic influences is based on limited scientific practices not real scientific research. They should be trying to work out why some observations do exist rather than saying that sometimes it doesn't work. I bet no one can pass a charged particle straight through any of our magnetic water conditioners without its trajectory being influenced by the magnetic fields. Scientists should realise that science isn't and end. It is a journey.

[Edster]

Despite all my qualifications, I have no explanation of how a magnet around a pipe can change the properties of dissolved and suspended ions and compounds.
I live in a seriously hard water area, you pour a glass from the tap and it says "who you looking at? you looking at my bird? outside!"

One of my friends also an engineer said this sounds mad, but those magnet things work.

IT ALL DEPENDS.

Some people bolt one on and nothing changes. Noone knows how this works so not a surprise.

It is not a placebo, kettle descale has gone from 2 weeks to 3 or 4 months, there is still stuff there, but it appears to self precipitate as tiny foggy granules in the water rather than scaling the heating element.

There are snake oil specials like one company that shows a coil around a copper pipe, hmmm that`s going to do a lot at AC as you claim. NOT! I ignore these as also pointed out by "which?"

Whatever the current orthodoxy,  I  have found that despite all my internal objections based on my education this does work, in some locations so It needs proper investigation. What is the difference in assay between where it works and where it doesn`t? no-one has done these tests.

I bought one of these because it was stupidly cheap and I was drunk.

Sober I have to come to terms with the results, and I cannot explain them.

[chris]

I think the best trial would be a blind trial whereby users were given real or "sham" units and not told which. They were then asked to report back on the effectiveness after say 6 months. Only when the results were declared and the code then broken to reveal a true effect will it be possible to say with any certainty that people are not merely reporting what they've like to see rather than the reality.

[Edster]

It is infuriating to have preconceptions dashed. Not double blind, but I had a negative expectation and I didn`t buy it thinking it would work,  it was a point of argument over a pint to wind a friend up over so he got defensive " oh well it was less than £5, what do you expect? Mine cost over £50 so of course it will work".


Much to my surprise It has done something as reported, I rinsed the kettle out recently, nothing on the plate element, no fizz from descaler.
I took the magnet thing off, and within a week spots of scale, that fizzed. Put back on and nothing. there is a slight haze as if a pinch of instant mashed potato or cornflour in solution sometimes which you don`t see with the magnet off.

It hasn`t done anything for the stored water in the loft tank that I can tell it still furs up anything it can.

Running the water and boiling immediately on plate type kettle (russell hobbs millenium) It isn`t scaling over the several months I`ve trialled it. It used to unless I filtered the water

I was adamant it wouldn`t work, copper is diamagnetic so it should be attenuating on a copper pipe, the geometry of the two magnets doesn`t encourage a radially piercing field, and was waiting to be able to say "didn`t work, sucker!".

I`ve worked on tape heads, hf and RF transformers and a variety things like TWT`s at the mod level from my phys/ electronics degree on. I cannot see how it can work, but the crudest put it on take it off test says it is doing something, but only on a fast flow near to the ruddy thing  and water subsequently boiled immediately.

It can`t do anything my head says in CAPITAL LETTERS   but the crude empirical evidence says it does. Fortunately there must be an eventual explanation, but I am at a loss and staying flexible.
this is real and observed not on drugs, and  a repeatable limited effect.

How many years have I heard anecdotally by otherwise sensible people this works? BUT ONLY in some places. A very good engineer now long retired, summed it up, "it looks like money for old rope, no-one has an idea exactly what is going on, It does work in some places, but £100 is a lot of money to risk if you don`t have it, and can`t take it back if it doesn`t work, I stick with chemical bags in the tank"

[lyner]

I installed an electronic one a couple of years ago or more. It's effect has been to produce softer scale which doesn't build up. You can scrape it off with a fingernail instead of a penknife and the kettle element doesn't look like a snowy scene any more. I don't need a double blind test; the evidence is pretty conclusive.

Btw, one of the Solar Heating companies (can't remember the name) expressly forbids the use of a magnetic  system cos it can clog the fine bore pipes with the very fine crystals that form.

[Bored chemist]

"I don't need a double blind test; the evidence is pretty conclusive."

That's exactly why you do need one.

[Edster]

The more esoteric effects I agree should be tested by identical houses, and installations( on a new estate?) by double blind with dummy units.

Empirically, due to my huge tea addiction, I can confirm that there is a cause and effect relationship between the permanent magnet and scale being deposited rather than hazing in solution in the kettle.

I was initially in denial but I have had to face the evidence.
I`ve stopped using my water filter to soften the scale which also made some tea show that metallic looking scum. The kettle is self descaler, once the scale reaches a certain thickness the flat element cracks the scale and a filter retains the bits. I`ve had this one 10 years, but 3 burned out due to scaling during the same period previously.

It has only made a difference to the bloomin` kettle, the valve in my tank has the filter clogged with scale yet again and the overflow is dripping, awaiting a cold day to go in the loft and drop the lot in vinegar.

Still It`s brilliant water for homebrewing strong ales! Hic!

[lyner]

"I don't need a double blind test; the evidence is pretty conclusive."

That's exactly why you do need one.

How many other engineering investigations involve double blind tests? Do they do double blind stuff at CERN?
You can do objective measurements and get objective answers without the need for double blind methods.  If I measure 12.3V on a meter, I don't ask someone to change the controls according to some random scheme and then do the measurement again. If there is an anomaly (a consistent variation from what was expected - not just a random error), I will look for an explanation. If I can't find an explanation, I will say I don't understand - not that the anomaly didn't occur.
This isn't medicine with placebo effects and self-healing systems (people)..
The only thorough investigation of which I am aware used a bench full of the old filter coffee makers. The build up of scale was clearly different with and without the magnetic inhibitor.  I don't see the problem that people seem to have with that.
There may be some chemistry involved which people don't understand but that doesn't mean that nothing happens.

[daniel]

the best way to test the effectiveness of magnets is to pour orange juice through a wine ring. As a liquid passed through a magnetic field it flips over some of the ions. + or - depending on which field you use S or N pole. Do you remember to make and acid or base one gives up and ion or takes an ion. So if you pass it one way it will give up ions making making the liquid more acidic if you pass it the other way it changes it to a bass. YOU can taste the difference. So in water softening you can only use a S pole magnet to do the work it will flip a hydrogen atom as the water passe through it changing calciumcarbonate to arognite.

[VirtuaMcPolygon]

Well after just installing a Magnaclean filter. The answer is: Yes they work. But not on limescale.

I was advised to get a magnetic filter from a british gas engineer. I asked the same question. How can magnets remove limescale as its non-ferrous.

They don't. As they are sold to remove Iron Oxide that builds up as black iron oxide sludge that clogs up your boiler and rads. This was causing my boiler to go wrong all the time. I always thought it was limescale. After I saw the condenser they had to replace in the boiler I can see why. It was jam packed full of iron sludge.

So I've fitted one and 3 days later I checked the magnaclean filter and it does work. It had started collecting iron sludge before it had entered the boiler to do damage.

I will still have to clean the filter out from time to time mind you. But it looks like it's working.

I suspect the cheap limescale removers that advertise wrapping magnets around the pipe don't work. If they do have any effect it would be only on the iron. And would only build up on that section of pipe. Being there is no filter to collect the iron oxide. That in term would only block the pipe over time and you would have to cut the pipe out and replace it with a new section. But I doubt the magnets would be strong enough to attract the iron to the side of the pipe.

Link

http://www.adeysolutions.co.uk/subprofessional2.asp?id=246

[Andrew]

I have some experience of this phenomena but not with the commercially made versions.

About 20 years ago I was working in a job where I could get old loudspeakers for nothing and was also renovating a house in Bath where the water is hard. I saw that the magnetic water treatment devices were for sale so, being a skinflint, I put a toroidal iron speaker magnet around the plastic water pipe where it entered the house. The house had a gas boiler and a copper indirect hot water storage tank.

My kettle did not get the usual hard coating of limescale but instead the water was misty when settled and had some loose particles of (presumably) lime.

About two years after I fitted the hot water cylinder I was obliged to move it. When I drained it there was about six inches of pasty bright green sludge in the bottom of the tank but nothing sticking to the element or coils.

I subsequently moved house (leaving the magnet where it was) to another house nearby and got hard limescale coating my kettle element. As I no longer had a source of speaker magnets but did have some spare neodymium magnets (half inch diameter about 1/8th inch thick with holes through the middle). I laid 11 of these stuck together along a horizontal 15mm copper pipe near the water entry to the house. My sink and kettle are about 15ft. further along that same pipe.

The hard coating has ‘gone’, by which I mean I didn’t chip it off, and kettle-boiled water is cloudy with particles in it but they settle quickly. Hot water from my current cylinder is clear (to look at) and I have no idea what its like inside but it has worked OK for 18 years with nil maintenance.

Obviously I have no explanation for how any of this might occur but if anyone wants to try it out they can do so for nearly nothing.

[John Reid]

It never ceases to amaze me on how many (experts) there are out there ready and willing to negate something that they themselves have never tried. If you have never tried it, you are not an expert, you're a commentator. I know from experience that the magnetic affects on minerals in water is for real. My experience with magnets have been positive with boilers, commercial dishwashers, and ice machines. When the scale goes away without using acids and phosphate feeders, your magnet is working. Pretty simple.

[Jeff]

I tried some magnets on my pipes for 3 months and they definitely resulted in less scale buildup.  No scale rings in my toilets, faucets did not have scale buildup and sinks were easier to clean.  Our water hardness is approximately 17 grains.  I've yet to drain my hot water tank (electric), but I expect the heating elements will not have the scale buildup they normally do.  I originally used three 4"x1"x1" ceramic magnets at the water main coming into my house and two the same size coming out of my hot water tank but now I'm experimenting with stronger rare earth magnets (2"x1"x1/4") to see if fewer stronger magnets can perform the same function.  The magnets work.  I don't know how, but they work.  

[Mike Williams]

Hi All, From our understanding a magnet Removes magnetite, rust and magnetic materials from heating systems to sub-micron level to stop sludge build up. http://www.fernox.com/equipment/filters/boiler+buddy
If you have problems with calc/scale, the best thing is a quantomat : http://www.fernox.com/equipment/scale+reducers/scale+preventer+quantomat.
If you have any more questions please get in touch with us www.busybees123.co.uk
Mike, Director of Busy Bees

[simin]

This idea is great works well I am provider of water pipe in uk,So these idea make sense

[Harry]

It's all about calcium carbonate that exists in three forms, aragonite, calcite and vaterite. If you can form aragonite crystals then you have taken some calcium carbonate out of solution and placed it into suspension.  This effectively reduces the saturation ratio of the components necessary to form calcium carbonate that are left in solution. Calcium carbonate is inverse soluble meaning if you heat the water it'll try and dump calcium carbonate in the form of calcite. The lower the saturation ratio the less likely calcite will be dumped.  The same applies to the other event that causes scale deposits, a pH increase. This occurs when pressure drops occur such as at shower heads and faucets. The drop in pressure causes carbon dioxide to be released from the water, carbon is acidic so when it's released from the water the pH of the water increases quite dramatically. In such situations scale can be deposited depending on the condition of the water. We've all seen scale build up on shower heads, that's why.  A way to control and prevent scale is to use a water softener that removes calcium and other elements from the water by ion exchange or use a proven scale prevention unit, an example of which can be found below, this site has decades of case studies and a science paper from the Harwell atomic research laboratory to sink your teeth into: http://www.fluiddynamicsna.com

[Nacho2012]

For an explanation on the effect of magnets you could have a read at the paper I had to post in a blog because the kind of people who says that magnets do not work dogmatically also refused to accept it: http://chemistry-f-talens-alesson.blogspot.com/.

Essentially, ions in water have a bulk phase concentration and a surface excess. Surface excesses are often much higher, and they are the ones involved in reactions, including precipitation. Precipitation or other reactions will occur if the build up of those surface excesses reaches a critical value. That's what my paper is about, and also about how maths can deceive us into thinking that we know the mechanism of something when we only have a black box correlation.

The magnets simply beat back the build up of the surface excesses and prevent the precipitation. But it can work the other way round: some companies sell devices for descaling of water prior to its use that usg magnets. What they are doing is forcing the build up to form faster in a tank with the help of the magnets. The decalcified water is then used.

The bottom line is that magnets COULD be used to step up other reactions or to prevent them, for as long as the species involved or at least some of them are ionic.

[wolfekeeper]

Uh huh to all the above.

Where are the double blind trials that support these people trying to sell stuff?

There aren't any. If people want to sell me something, they're going to have to go through the publication process in a reputable journal; the plural of 'anecdote' isn't data.

[Bored chemist]

For an explanation on the effect of magnets you could have a read at the paper I had to post in a blog because the kind of people who says that magnets do not work dogmatically also refused to accept it: http://chemistry-f-talens-alesson.blogspot.com/.

Essentially, ions in water have a bulk phase concentration and a surface excess. Surface excesses are often much higher, and they are the ones involved in reactions, including precipitation. Precipitation or other reactions will occur if the build up of those surface excesses reaches a critical value. That's what my paper is about, and also about how maths can deceive us into thinking that we know the mechanism of something when we only have a black box correlation.

The magnets simply beat back the build up of the surface excesses and prevent the precipitation. But it can work the other way round: some companies sell devices for descaling of water prior to its use that usg magnets. What they are doing is forcing the build up to form faster in a tank with the help of the magnets. The decalcified water is then used.

The bottom line is that magnets COULD be used to step up other reactions or to prevent them, for as long as the species involved or at least some of them are ionic.

You seem not to have read or understood your own blog.
It doesn't mention magnets.

So, I could copy your post but change each instance of "magnets" to the acronym "SYFIYE" and it would be every bit as meaningful.

(SYFIYE =sticking your finger in your ear).

[CZARCAR]

water is ionic & freeze expansion is proof? Proper magnetization may work?