North-facing Thanet seafronts - Cliftonville, Kingsgate, the Broadstairs North Foreland ridge, the Ramsgate West Cliff, Westgate seafront - see two decades of chloride-laden onshore wind on their electrical intake. Consumer units age differently on the CT9 seafront than they do inland at CT10 St Peter's. Five visible red flags to check on your board.
1. Rust bloom on the meter tails
The tails between the incoming service head, meter and consumer unit are the corrosion-first component. Copper conductors don't rust, but the crimped lugs, the tails-cover screws and the earthing block terminals do. Orange-brown bloom on any of the metalwork is the visible signal. On an inland board this may take 25-30 years to appear; on a Cliftonville north-facing install it appears in 10-15 years.
2. Greening (verdigris) on the neutral bar
The neutral bar inside the consumer unit sees more atmospheric moisture than the phase side because it's typically at slightly higher relative humidity. Chloride ingress produces a green-blue verdigris on the copper. Small amounts are cosmetic; a visible layer means the joint resistance is climbing and the board should be replaced.
3. Burnt-plastic or "hot-electrical" smell
A pre-2016 plastic split-load consumer unit that has begun to overheat internally will smell of hot plastic even when nothing has visibly failed. This is a C1 code on an EICR and needs immediate attention - the enclosure fire-propagation issue that drove BS 7671:2018 to require metal enclosures was based on exactly this failure mode.
4. Visible pitting on the enclosure
Metal-enclosed boards (post-2016) will pit rather than burn. On a Kingsgate or Ramsgate West Cliff install you can see the enclosure paint bubbling and the underlying steel pitting through at the seams within 8-10 years if the enclosure is not IP-rated to at least IP54 and mounted outside. Inside-mounted metal boards typically outlast the property owner.
5. RCD "test" button doesn't trip
Every RCD (residual current device) has a test button that mechanically simulates a fault and confirms the trip mechanism. If your board's test button doesn't produce an audible click and shut off the associated circuits, the RCD has failed internally. The regulation is to test monthly; almost no domestic property owner does. At the EICR we test all RCDs to their rated trip time (30mA in 40ms typically) - a failed test is a C2 code.
What to check yourself, safely
Turn off the main switch first. Then look - do not touch inside the board. Any visible rust, greening, blackening, cracking or smell of hot plastic is a call-us signal. Test buttons can be pressed with the main switch on but no need to open the cover.