Hi, the MCB on my split circuit consumer unit is tripping sporadically, sometimes when nothing is connected to the downstairs socket circuit. The MCB protects the RCD protected circuits (upstairs and downstairs sockets, cooker, hot tank, kitchen sockets). The hot tank and cooker circuits are turned off at the rcd and are not connected used/connected yet.The light (non-RCD'd) circuits stay on when the RCD trips.
Please can someone tell me what causes an MCB to trip, other than overcurrent, and not trip an RCD, and hopefully some possible things to check in order to locate the fault.
This 'may be' heating associated but does happen when the heating is off and the boiler is off i.e. could it be associated with hot pipes near a cable?
Many thanks.