Electrolytic Scale Inhibitor any good?

NSG666

SESI | Water Conditioner | Sentinel (sentinelprotects.com)

I've fitted a few of these type things in the past at the homeowner's request but really have my doubts as to their effectiveness - that's if they do anything at all. If they were any good I'd expect to see reviews and recommendations from the likes of Which? along with test results on treated and untreated water. Even when they get good reviews on e.g. Screwfix I'm sceptical as the comments are very much subjective. Any thoughts on here?

I'm not looking for info on alternatives such as boilermate etc as I've lived in my home for 24 years and it's not that much of a pain to descale the kettle when my tea starts to look scummy or worse still I get a mouth full of bits. If you want to mention alternatives for the benefit of other readers that's fine. Ta

Section62

NSG666 said:

If they were any good I'd expect to see reviews and recommendations from the likes of Which? along with test results on treated and untreated water. Even when they get good reviews on e.g. Screwfix I'm sceptical as the comments are very much subjective. Any thoughts on here?

Same here. Unless you make chemical changes to the water (i.e. as in an ion exchange softener) I can't see how the the physical properties of the water can be changed by just passing through 'something' in a fraction of a second.

On the other hand, credible people including industrial users swear by them.

I was given a secondhand one, and have been planning to install it as my water supplier has changed the local source and the water has got harder.  But it has taken more than 4 years for me to still not get round to doing it... which is possibly a comment on my feelings about whether it will actually work, as much as being busy with other jobs.

FreeBear

NSG666 said: Even when they get good reviews on e.g. Screwfix I'm sceptical as the comments are very much subjective. Any thoughts on here?

Let's see some independent, peer reviewed scientific reports... I've looked, but can find none.

Section62

FreeBear said:

NSG666 said: Even when they get good reviews on e.g. Screwfix I'm sceptical as the comments are very much subjective. Any thoughts on here?

Let's see some independent, peer reviewed scientific reports... I've looked, but can find none.

Which makes it all the more strange that trusted brands not only supply them, but refer to them as a requirement of BS 7593...

https://fernox.com/blog/articles/bs-75932019-what-you-need-to-know/

For hard water areas with a ppm of 200 and above, a scale reducer should be fitted to mitigate the effects of limescale. Electrolytic Scale Reducers offer whole house protection whilst Magnetic Scale reducers are designed to be fitted next to the boiler for single appliance protection.

I haven't looked at BS 7593 but the same requirement is mentioned on many different sites, so I don't doubt what Fernox say. I just find it puzzling that something which has made it into a BS as a requirement in certain circumstances isn't something that proof of effectiveness can be readily found.

It does appear that work is going on to define a standard though - https://www.energysavingtrust.org.uk/sites/default/files/LCD and Filter Minutes_Meeting held on 28.10.15_final.pdf

FreeBear

Section62 said: I haven't looked at BS 7593 but the same requirement is mentioned on many different sites, so I don't doubt what Fernox say. I just find it puzzling that something which has made it into a BS as a requirement in certain circumstances isn't something that proof of effectiveness can be readily found.

Using a different set of search parameters, I found something that gives a brief insight in to how these things are supposed to work - https://www.ciphe.org.uk/newsroom/2016/part-l-compliance-guide/

2. Use an electrolytic scale inhibitor. These devices, often known as 'inlines', are the cheapest option and they are ‘fit and forget’. There is no maintenance regime or replacement cartridge to buy over a potential 10-year life span. They work by releasing zinc into the supply which becomes a nucleating site for calcium bicarbonate in solution. This disrupts the crystal structure of scale from tenacious calcite to fluffy aragonite, which is less likely to form immovable deposits. They do need replacing once the beneficial effects subside. Even if replaced on a two-five year cycle, they will always be the cheapest option.

So these devices don't actually prevent the formation of scale, only converts some of it in to a less tenacious form and reduces the propensity for it to form hard layers. But they do not completely eliminate scale, nor do they remove the calcium compounds from the water.

coffeehound

FreeBear said:

So these devices don't actually prevent the formation of scale, only converts some of it in to a less tenacious form and reduces the propensity for it to form hard layers. But they do not completely eliminate scale, nor do they remove the calcium compounds from the water.

Yes that was my understanding; whether magnetic, HF electric field or apparently these ones, they claim to make the scale form particles which get swept through heaters, etc, without plating out onto hot surfaces.  NSG666's link states something about independent tests, though strangely neglects to mention anything about who c/o the tests.

FreeBear

Where one of these devices would help is if it was plumbed in to the heating system inline with a magnetic filter. The zinc would help to prevent the steel radiators & boiler internals from rusting - Cathodic rust protection using zinc is a well established process based on well documented scientific principles.

Section62

FreeBear said:

So these devices don't actually prevent the formation of scale, only converts some of it in to a less tenacious form and reduces the propensity for it to form hard layers. But they do not completely eliminate scale, nor do they remove the calcium compounds from the water.

Yes, looking at the Fernox stuff earlier I found a YT video presentation by Fernox which included one of theirs which could be dismantled to show the inner workings.  Effectively a zinc sacrificial anode and not much else.

https://www.youtube.com/watch?v=INeAAKg8PMA

There are suggestions elsewhere that these devices work for some people but not others - so possibly being a case that the chemistry of the individual household water supply is an important factor in whether or not the sacrificial anode process will function or not?

I also found references to a German 'standard' called "DVGW W512".  There's an "English translation" I found, but didn't (and won't) link to it because I'm not sure about the company or the copyright situation.  But googling those terms should bring it up near the top of the results.

NSG666

Thanks for the responses so far. Sorry I forgot that some were used in heating systems too, I was thinking about them in the case of potable water.

NSG666

Thanks again all. In fairness I was expecting the type of replies that I received but was hoping one of you regulars who have responded or Jeepers etc. might pop up and say "I have one in my house and they are (no)good"

Another_Level

Over the years of working in areas where the water comes from different reservoirs, one side of the road has hard water and the other side of the road has softer water 
Electrolytic inline items in hard water areas will slowdown damage done to gas combination boilers when fitted correctly, iirc they instantly prevent more scale adhering to inside plate heat exchangers and pipes flowing to taps showers etc, So i imagine the scale is made less sticky and flushed out via hot water outlets.


Doubt they will make much difference for filling electric kettles, but its been known to empty an electric kettle and allow the element to dry. Never leave previously boiled water water fermenting in bottom of the kettle  was mentioned on a holiday cooking type programme.

Electric Boil taps, are available and they come with detailed instruction on how to descale their tank and associated fitments

Water