Safety

7 Signs Your Consumer Unit Needs Replacing

Most homeowners don't think about their consumer unit (fuse board) until something goes wrong. But an ageing or inadequate board is one of the most common causes of electrical faults, fire risk and failed property surveys. Here are the signs to look out for.

1. It has rewirable fuses rather than MCBs

Older consumer units use ceramic rewirable fuses — thin wire that melts when overloaded. Modern units use MCBs (Miniature Circuit Breakers) that simply trip and reset. Rewirable fuses are slower to respond, harder to reset safely and don't offer the same level of protection. If your board looks like this, it's overdue for replacement.

2. There are no RCDs

RCDs (Residual Current Devices) protect against electric shock by detecting earth faults and cutting power in milliseconds. Current regulations require RCD protection on most circuits. If your consumer unit has no RCDs, you're missing a critical layer of protection — especially important for circuits supplying bathrooms, kitchens, outdoor sockets and garden supplies.

3. Breakers trip frequently

Occasional tripping is normal, but if circuits trip regularly under normal load it can indicate overloaded circuits, a fault in the wiring, or an ageing consumer unit that's no longer operating correctly. Persistent tripping should always be investigated rather than reset repeatedly.

4. There's a burning smell or discolouration around the board

Any smell of burning plastic or scorch marks around the consumer unit is a serious warning sign. This can indicate arcing or loose connections inside the board — both of which are fire risks. Turn off the main switch and call an electrician immediately.

5. The board is full — no spare ways

If you're adding new circuits (EV charger, garden room, new kitchen circuits) and there are no spare ways in the consumer unit, the board will need upgrading. Bodged solutions like double-pole breakers on single-pole ways are unsafe and non-compliant.

6. It failed an EICR

A C1 or C2 observation on the consumer unit itself is a clear indicator that replacement is needed. Common EICR failures include: no RCD protection, deteriorated wiring connections, no main switch, or a board that doesn't comply with current standards.

7. The board is more than 25–30 years old

Consumer units don't last forever. Components degrade, insulation deteriorates and older boards simply weren't designed for the loads modern homes place on them (EVs, induction hobs, underfloor heating, heat pumps). If your board is significantly older than 25 years, an assessment is worthwhile even if nothing has failed yet.