I agree with the previous answers and would urge you to get a qualified electrician to check your work.
Not only is working on the combination of water and electricity highly dangerous if you do not know what you are doing (Which I am afraid you have clearly demonstrated is the case.) but in the UK is actually illegal unless the work is inspected and passed by a "Competent Person".
A more likely answer would be that you have wired the mains to the output side of the switch therefor putting power to the neon all the time instead of when switch is on
https://uk.answers.yahoo.com/question/index?qid.. go to this link and you will see your answer, you have bypassed the switch wire , thats why its on red all the time ... In other words you have one wire in the wrong place, the power is going to the (shower unit) all the time..
ceiling switch for shower?
Please wait ...
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