RCD in consumer unit keeps popping, replaced with new one, still same issue

[Octopus]

So you are saying it would be more likely a faulty RCD rather than a Circuit fault? Disagree

I was disagreeing with the post that ruled out a faulty RCD ....

Tripping RCD's can be caused by:

1. Issue with the incoming supply
2. Faulty RCD's
3. Earth leakage from appliances
4. N-E faults on RCD circuits
5. N-E faults on non RCD and RCD circuits
6. Faulty appliances

etc etc

 

[Chivers]

The shower is still working but doesn't get used? The Neutral and earth are still connected even if the MCB is switched off (others have mentioned this). When RCDs trip I always think water or poor insulation resistance. I'd be tempted to remove the shower neutral & earth (and tape up) in the first instance unless it can be totally isolated? This will eliminate that circuit without an unnecessary disruption to circuits that are being used.
It does seem odd to wire the RCD in with circuits either side rather than just to the right with one length of bus bar - looks like it's been an afterthought.