Does leaving water in kettle cause scale, or boiling it? Adjudicate argument with DH...!

[Wigeon]

Does anyone know if leaving a bit of water in the kettle contributes to the limescale, or is it just the action of boiling the kettle? We live in a very hard water area and the kettle gets very scaley. DH reckons leaving some water in the kettle makes no difference. I think we should empty out the kettle in case the standing water is making the scale worse.

AIBU or is he BU?

Any contact with hard water will eventually leave scale in the kettle. The longer you leave water in it, the faster your kettle will scale up.
Boiling it should, I think, reduce the rate of build up due to the movement, but I could well be wrong.
You do need to empty it (and preferably dry it, but who'd do that?) after use to prevent build up.
Just fill it with vinegar once a week, empty it and rinse very well to descale.

Scientifically boiling the water causes the limescale to form. The heat speeds up the reaction, as the steam is produced and the salts ( calcium carbonate or magnesium carbonate) are formed.

Ha - so one to me, nil to DH then so far...!

you should absolutely NOT leave water in the kettle in a hard water area.

I have been telling this to DH for years, to no avail.

I only buy cheap kettles because of his habit of never emptying them, they get ruined.

Oh, cross-posted - so, itshappened, do you mean that standing water doesn't cause the receptacle to get scaley?

Just leaving water in it will cause a small amount of limescale to build up, but life is too short to be emptying kettles every time IMO. I'm on your dh's side.

However we do use filtered water in the kettle for making tea because it tastes nicer and you get less limescale build up.

I suspect emptying it and not drying it would be worse than leaving some water in because it will crystallise out as the residual water evaporates. But to be honest, regular descaling is going to be needed whatever you do.

You don't have to boil the water for limescale to form - it will form when the water evaporates, which will also happen, though more slowly, at room temperature (eg on a water glass left with cold water in for several weeks in a spare room )

I wouldn't have thought leaving boiled water would contribute to timescale, as most of the minerals that contribute to the limescale will precipitate out on boiling.
Technically, leaving water standing and evaporating will leave a small amount of deposits, but also waste water pouring away excess every time.
I'd buy a big bottle of vinegar when you see it, and heat the vinegar (don't recommend boiling, it stinks the kitchen out!) When the limescale builds up.

The biggest problem, though, is that if hard water is heated past 55°C or left to stand, the dissolved minerals in it solidify as the moisture evaporates. These solidified minerals are what limescale is made of, and they can be a serious problem in the home. As you’ve probably noticed in your own home, limescale will often cover taps and hard surfaces with an unsightly layer which can be difficult to remove.

www.water-guide.org.uk/limescale.html

I've no idea, but it's a right royal pain. We too live in a hard water area and have gone through multiple steam mops and irons because of it. I now use bottled water for these and the coffee maker and filtered water for the kettle. It does make heaps of difference, despite it being annoying.

That's really interesting maddy. We have a water softener so I dread to think how bad it would be without that!

So sounds like standing water in kettle = creates a bit of the scale; boiling the water = creates a lot of the scale...?

I do regularly vinegar the kettle, which does work, but it scales up so quickly and it is a bit of a faff, so anything which can help is good!