Can remove limescale from unvented direct cylinder (center store)

[stelio]

I have an unvented direct cylinder from centerstore to use it only for hot water CenterStore direct unvented cylinder 120ltr | Wolseley - https://www.wolseley.co.uk/product/centerstore-direct-unvented-cylinder-120-ltr/ but with two immersion heaters.
I had it the cylinder working fine for 4-5 years but now the upper resistance has broken and it seems due to limescale and debris and I am also concerned with the electrical consumption....
my plumber told me that there is no way to get the limescale out of the cylinder as it is and I was looking for a second opinion
Removing limescale with hoover / pump would work for my circumstances?

 

[ShaunCorbs]

If it’s loose yes but if it’s solid / stuck to the walls no best option new cylinder and sort the limescale issue out eg softener

 

[king of pipes]

I've had some success with Fernox DS3 have a read up it really depends on how bad it is you will definitely need a decent wet vac to suck out the dissolved debris and it's a messy job . Kop

 

[Chuck]

Is the water in your area known for be very hard?

Assuming this is a typical domestic setup, the upper 'boost' element will get much less use compared with the lower 'Economy 7' main element. If so, it's surprising that the upper element has failed due to scale before the the lower element.

Was the 'scale' diagnosis confirmed by removing the upper element and making a direct visual check of the interior?

Five years seems a bit soon to require a new cylinder, even in a hard water area.