No, you can't.
The cable is not large enough to supply the shower, you will need to get the electrician to install a new circuit, and advisably do a PIR looking at that 'round gadget' wiring (its a jb btw).
Please, for the safety of you and your family, use a competant electrician.
Do you not think that the electrician would have done what you are suggesting if it were possible?
Do you have a bath?
There you go - £300 saved.I have a bath
What boiler do you have?
If it's a combi, you shouldn't need to pump it.
If you have a normal hot water cylinder, you should be able to add a pump to this for your shower.
There you go - £300 saved.I have a bath
It's very difficult to relax and snooze in a shower.
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