Black scale/flakes in kettle - softened water

worlestone

We had a water softener fitted a couple of years ago and since then the limescale in the kettle has been replaced by black/grey scale which flakes off into drinks.  Has anyone encountered this with softened water before? It does seem like replacing one problem with another!

We tend to fill the kettle with 50/50 cold/hot water as the hot tap is softened and the cold is not.  We live in an area with very hard water in Dorset

ThisIsWeird

I don't think you should be drinking 'softened' water.
Unless your softener uses a system that provides potable water, the cold kitchen tap should remain direct from your mains, and be the only source of drinking water. 
Afaik.

Keep_pedalling

You should not use water from the hot tap for cooking or making tea, as it can contain contaminates. The fact your hot water is turning limescale black shows that your hot water is indeed contaminated and should only be used for washing. 

Adding a water softer to an existing system can increase the amount of contaminates as any previous build up of scale in the pipes can be desolved by the softened water and there can be other contaminates contained within the limescale and these will mainly be metallic elements.

Emmia

You should only be filling the kettle with water from the mains, this means that although you have softened water elsewhere, the kettle will still need descaling.

ThisIsWeird

There - that's you told :-)

The good news is that hard water is healthier for you.

Rodders53

Here's just one softener makers statement on drinking softened water https://www.harveywatersofteners.co.uk/faq/softened-water-safe-drink/
Babies and those on very low sodium diets are the only groups advised to not drink softened water.

SWMBO doesn't like the taste of softened water here, nor tea made with it.  Whole house is softened as the incoming main is in the attached garage and a very long way from the kitchen. (Softener was fitted by previous owner.)  So we fill bottles from a tap in garage for drinking and making tea.  (I'll happily drink softened tap water. I haven't the same taste buds as my wife.).

Black bits are quite possibly due to a breakdown of a flexi-pipe rubber lining?  Or some unvented HW cylinders had an air bubble 'baffle' that degraded with time?  Probably unwise to fill or drink from any hot tap, softened or mains water.

worlestone

Thanks for the replies, appreciated, though I was not asking whether it's safe to drink softened water, it is and we do (https://www.dwi.gov.uk/consumers/learn-more-about-your-water/water-filters-and-softeners/). 

I was asking whether anyone had experienced the grey/black scale, not limescale. This only forms in the kettle, it's not within the water source, either hot or cold supplies. The hot water system is a recently installed non vented pressurised system, so direct from mains with no cold water tank.

Thanks anyway

Photo of the kettle attached

badmemory

I have lived in areas with both hard & soft water & in one (where the kettle barely lasted a month) with a large water softener & I have never come across that.

Keep_pedalling

worlestone said:

Thanks for the replies, appreciated, though I was not asking whether it's safe to drink softened water, it is and we do (https://www.dwi.gov.uk/consumers/learn-more-about-your-water/water-filters-and-softeners/). 

I was asking whether anyone had experienced the grey/black scale, not limescale. This only forms in the kettle, it's not within the water source, either hot or cold supplies. The hot water system is a recently installed non vented pressurised system, so direct from mains with no cold water tank.

Thanks anyway

Photo of the kettle attached

The point we were trying to make is that is not safe to use the hot water supply for drinking, not that it is not safe to drink softened water. 

silvercar

We drink softened water and have never had that problem. I would suggest that you should only be using cold water in your kettle, not from the hot tap.

ThisIsWeird

Keep_pedalling said:

worlestone said:

Thanks for the replies, appreciated, though I was not asking whether it's safe to drink softened water, it is and we do (https://www.dwi.gov.uk/consumers/learn-more-about-your-water/water-filters-and-softeners/). 

I was asking whether anyone had experienced the grey/black scale, not limescale. This only forms in the kettle, it's not within the water source, either hot or cold supplies. The hot water system is a recently installed non vented pressurised system, so direct from mains with no cold water tank.

Thanks anyway

Photo of the kettle attached

The point we were trying to make is that is not safe to use the hot water supply for drinking, not that it is not safe to drink softened water. 

I can only guess that these are 'salts' that have come out of the water. Now, whether they are the original calcium-based salts from your hard water which have got past the softener, or whether it's the sodium-based salts which I understand are used to flush out the filters, I don't know.

And, why they are black, I don't know either. Perhaps from just being heated by the kettle element? Or mixed with other impurities in the water. 

Keep-ped, do you have an actual 'filter' added between the softener and the kitchen tap? That might help. 

If you can get hold of a decent flake, could you try holding it in a blow-torch gas hob flame?!

Sodium should give the classic sodium-yellow flame, and calcium an, um, I'll need to look it up...

Science at Christmas. :-)