Turn off the power, prove it's dead, then swap the blown fuse inside the fused spur for the correct rating.
FS-01Work out the right fuse ratingCheck the appliance it feeds or look at the old fuse's colour band and printed rating. Small loads like lighting circuits usually take a 3A fuse; heaters, immersion heaters and most other appliances take 13A. Buy a matching BS 1362 cartridge fuse before you start.
1 pack · BS 1362 cartridge fuse, 3A or 13A (match old fuse)
FS-02Switch off the fused spurFlip the switch on the fused spur to off. This stops the appliance but the spur's own terminals and faceplate can still be live from the circuit behind it, so don't open it yet.
FS-03Isolate the circuit at the consumer unitFind the MCB feeding this circuit and switch it off. If it isn't labelled clearly, turn off the main switch instead. Never rely on the local switch alone before opening any wiring accessory.
FS-04Prove the spur is deadUsing your voltage tester, check it works on a known live source first. Test across the terminals inside the spur to confirm there's no power, then check the tester again on the live source afterwards. Do this every time, even if you're sure the power is off.
FS-05Remove the faceplateUndo the two screws holding the faceplate, usually one at the top and one at the bottom. Ease the plate gently away from the wall — it's still connected by wires, so don't pull hard or let it hang unsupported.
1 each · Screwdriver (flat-head or Pozidriv, matching your screws)
FS-06Find and remove the old fuseThe cartridge fuse sits in a small holder — either a clip-in carrier behind the switch or a screw-cap holder on the faceplate. Release it and pull the fuse out. A blackened glass tube or a snapped wire inside confirms it's blown.
FS-07Fit the new fusePush the new fuse fully into the holder, making sure both end caps make good contact. Click or screw the holder back into the spur securely.
FS-08Reassemble the faceplateTuck any loose wires back into the box neatly so nothing is trapped. Screw the faceplate back on, snug but not overtightened — plastic fascias crack easily if you force the screws.
FS-09Restore power and testSwitch the MCB back on at the consumer unit, then flip the fused spur switch to on. Test the appliance it feeds. If it doesn't work, or the new fuse blows straight away, stop — this points to a fault, not just a worn-out fuse, and you need a qualified electrician to check it.
FS-10Tidy upDispose of the old fuse safely in general waste. Wipe down the faceplate if it's dusty, and keep a spare fuse of the right rating handy for next time.
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