I was at a kitchen store a few days ago and saw that they sell what basically amounts to a tangle of stainless steel wire; you're supposed to put it in your electric kettle to attract scale buildup on the wire, and I guess in the process reduce the amount of scale buildup in the kettle itself.

1. do you think these things have any appreciable effect, or are they a useless gadget?
2. do you suppose, if it performs as advertised, that it could have use in espresso boilers?

It could work, since there are such things as scale magnets -- for instance, a misdesigned boiler fill valve on the original Synesso which scaled up completely while everything else was still pristine. If one could do that on purpose with throwaway parts, it would could work to keep the sensitive parts downstream clean.

Unfortunately, I have no idea whether a scrunchy would do the trick. I believe that with the inadvertent scale magnets, an electric field usually plays a part, but I'm completely ignorant how this works.

Water heaters have something like this. I don't know how well it works.

Water heater sacrificial anodes are there to prevent corrosion from electrolysis, where by a magnesium or aluminum alloy metal would prevent the zinc or iron from oxidation cation exchange and loss.

Therefore in this case it would have nothing to do with scaling. But that scrunchy could be offering an effect in a totally different way.

-Cecil

Sounds like a bunch of fluff to me. Even if it did work, how would you get it in and out of a boiler? You would probably spend more time opening up a big access port on the boiler to remove it then you would spend doing an old fashioned descale, and you would not have to worry about the port leaking water.

My guess - just a guess - is that there would not be anything magical or chemical about it.

It would provide a large surface area for scale to grow on. Some of the scale normally coming out of your water would happen to end up on the scrunchy instead of on your boiler, so it technically would reduce by a little the amount of scale that ends up on your boiler. Same amount of scale, with more area to deposit it. But you'd still definitely have scaling on your boiler, and still have to de-scale it the way most people do.

Since you have to do that anyway, what do you gain by somehow inserting and removing the scrunchy in your boiler?