Norwich · Norfolk
Fuse Board Keeps Tripping? Causes and Safe Advice
A consumer unit (fuse board) that trips repeatedly is protecting you. The causes split into three groups:
The three causes
1. Overload — too much on one circuit. Kettles, heaters, air fryers on the same socket ring. The trip is the circuit breaker (the narrower switches). 2. Earth leakage — a damp or failing appliance leaking tiny current to earth. Trips the RCD (the bigger test switch). Culprits: kettles, washing machines, dishwashers, old immersion heaters, garden equipment after rain. 3. Wiring or unit fault — damaged cable (nails in walls are classic), degraded insulation in pre-1980s Norwich housing, or a failing RCD itself.
The isolation routine
With the RCD tripping:
1. Unplug everything on the affected circuits (or switch all socket switches off). 2. Reset the RCD. If it holds, plug in appliances one by one until it trips — the last one is the culprit. 3. If it trips with everything unplugged, switch off all circuit breakers, reset the RCD, then bring circuits back one at a time. The tripping circuit contains the fault.
When to stop and call
- The RCD trips instantly with everything disconnected.
- Any burning smell, warmth at the board, or buzzing.
- The same fault recurs weekly.
- Your unit has no RCD protection at all (older units) — that is an upgrade conversation regardless.