Remove Trevi A2219AA Ideal Standard CLASS fixed shower head

[picaso]

Trevi A2219AA Ideal Standard CLASS fixed shower head.
Can anyone tell me how to remove this fixed shower head and replace it with a standard fit hose shower. I’ve not seen one of these before. It has a castellated ring as can be seen in the photo, does that need to be turned first. What tools will I need.

 

[CBW]

Is this one a spare on the photo, or have you already removed it? Have you tried to turn it anti-clockwise?

 

[picaso]

The whole body turns to direct the shower so impossible to unscrew. It looks like you need to unscrew from the back, but its behind a wall I dont want to damage. I was hoping it can be removed from the front with access under the bellows but its difficult to get at the inside to see what needs to be done.

 

[CBW]

Maybe try Idealstandard technical helpline then, they’re pretty helpful whenever I’ve contaced them.