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Replacing storage heater on original circuit?

Eboy

Hi

If I replace a faulty storage heater with a new one but no change to old existing circuit, do I need to upgrade the circuit to include an RCD? The existing circuit was wired around 1995 in good condition on MCB but no RCD protection.

I know if the circuit is altered then new regs apply but what about just changing the fixed appliance?

Thanks in advance!

Parents
  • +1

    As a general principle, as far as installation is concerned, new regs only apply to new work - just the new work, not the rest of the circuit, not the rest of the installation.  On occasions that might mean that some of the existing installation may need improving to allow your new work to comply (e.g. for an extended circuit to have an adequate Zs, or bonding to be present, or acceptable voltage drop). Sometimes improving some aspect the existing is a simpler and neater way of achieving compliance for the new (e.g. swapping an MCB for an RCBO at the start of the existing circuit rather than inserting an RCD as the start of the new work) - but that's an individual design decision, rather than a requirement of BS 7671.

    There is an urban myth that any work on a circuit requires the entire circuit to be brought up to current standards - but nothing in BS 7671 demands that - and that sort of thinking quickly ends up getting silly - e.g. having to oversleeving every existing red/black existing connection with brown/blue (or green with green/yellow for even older installations) ... the sort of thing that Dr Johnson would describe as "like fitting wheels to a tomato - time consuming and completely unnecessary".

       - Andy.

Reply
  • +1

    As a general principle, as far as installation is concerned, new regs only apply to new work - just the new work, not the rest of the circuit, not the rest of the installation.  On occasions that might mean that some of the existing installation may need improving to allow your new work to comply (e.g. for an extended circuit to have an adequate Zs, or bonding to be present, or acceptable voltage drop). Sometimes improving some aspect the existing is a simpler and neater way of achieving compliance for the new (e.g. swapping an MCB for an RCBO at the start of the existing circuit rather than inserting an RCD as the start of the new work) - but that's an individual design decision, rather than a requirement of BS 7671.

    There is an urban myth that any work on a circuit requires the entire circuit to be brought up to current standards - but nothing in BS 7671 demands that - and that sort of thinking quickly ends up getting silly - e.g. having to oversleeving every existing red/black existing connection with brown/blue (or green with green/yellow for even older installations) ... the sort of thing that Dr Johnson would describe as "like fitting wheels to a tomato - time consuming and completely unnecessary".

       - Andy.

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