No RCD on the board at all, or only one covering the entire house, so a single fault anywhere kills every circuit including the fridge and freezer. It’s a common setup in older homes that were never fully rewired, and it means one small issue can take out everything at once.
Why this comes up
An older board that was never upgraded to individual circuit protection.
A single RCD covering too much, so nuisance tripping affects the whole house.
A safety inspection or landlord compliance requirement.
Wanting the fridge and freezer on their own protected circuit so a fault elsewhere doesn’t spoil food.
A previous safety inspection recommending individual circuit protection.
Simply wanting the peace of mind that one appliance fault won’t cut power to the whole house.
How we handle it
Check the board has physical capacity for individual RCBOs.
Split circuits so one fault doesn’t take out the whole property at once.
Install and test trip times against the required standard.
Certify and label the board clearly so it’s obvious what protects what.
What to expect
Half a day for most homes. We label every circuit properly while we’re in there, which is worth more than people expect at 2am when something trips and you need to know exactly what to check. We’ll also check your existing circuits are labelled accurately, since boards in older homes are often labelled incorrectly or not at all after years of changes.
What it costs
Priced per circuit protected. Doing them all at once is considerably cheaper per circuit than coming back to add one at a time later. If you’re already having other consumer unit work done, adding RCDs at the same time is more cost-effective than a separate visit later.
Common questions
What's the difference from a circuit breaker?
A breaker protects the wiring from overload. A RCD protects you from electric shock. A modern board needs both.
Why does my RCD trip for no obvious reason?
A single switch covering too many circuits picks up small nuisance trips from anything on that group. Splitting circuits usually fixes it.
Can the fridge be on its own circuit?
Yes, and it’s a common request once people realise a fault elsewhere in the house can otherwise take out the fridge along with everything.
How do I test a RCD myself?
There’s a test button on the switch itself, press it and it should trip immediately. If it doesn’t, call us. Most people should test theirs every few months.
Do I need a RCD on every circuit?
Ideally yes, an RCBO per circuit rather than one switch shared across several. It costs more upfront but means a single fault only ever takes out one circuit, not the whole board.
Is one RCD ever enough for a whole house?
It meets the bare minimum in some older installations, but individual circuit protection is the current standard and what we’d recommend for genuine peace of mind.
How often do RCDs fail?
Rarely, but they should still be tested regularly using the test button. A RCD that doesn’t trip when tested needs replacing.