Does a kitchen cooker hood need its own dedicated circuit?

No. A domestic cooker hood draws only 100–300 W, so it can take a spur from the kitchen ring main via a fused connection unit (FCU). A dedicated circuit would be wasteful. The FCU provides local switching and the correct fuse protection for the hood's flex.

What fuse should I use in the FCU for a cooker hood?

A 3 A fuse is correct for most domestic cooker hoods. At 230 V, a 3 A fuse will carry up to 690 W, which is well above the typical 100–250 W hood motor and light combined. Check the manufacturer's specification if in doubt.

Is wiring a cooker hood Part P notifiable work?

If you are replacing a like-for-like connection (FCU to FCU) on an existing circuit, it is not notifiable. If you are running a new cable to a position where there was no supply before, that constitutes new circuit work and must be notified to building control unless carried out by a registered competent person.

My cooker hood came with a plug — do I have to hardwire it?

No. Many cooker hoods are supplied with a 13A plug and are designed to connect to a standard socket. If there is a switched socket nearby and the cable can be routed neatly, plugging in is perfectly acceptable. The switch on the FCU or socket gives the local isolation required by BS 7671.

Where should the FCU or socket be in relation to a gas hob?

Keep the FCU or socket outside Zone 2 around any gas appliance. In practice this means at least 150 mm to the side of the hob, or positioned behind the hood canopy rather than directly above a burner. For electric induction hobs there is no gas zone to consider, but the FCU should still be accessible and not hidden.

How to Wire a Kitchen Cooker Hood (UK)

Helpful video reference. We reference the Artisan Electrics video "How to install Cooker Hood #electricalvideos #bs7671" as the video reference here. Artisan Electrics is a Cambridge-based electrical company with a highly popular UK electrical YouTube channel. Their content covers BS 7671 wiring regulations and UK-specific installation practice throughout.

Before you start. Isolate the kitchen ring main at the consumer unit and test dead at the socket or planned FCU position before drilling or connecting anything. A kitchen ring can feed fridges, microwaves and other appliances that may still be live at adjacent sockets even when one outlet is switched off — always isolate the whole ring MCB, not just a local switch. If you are unsure which MCB feeds the kitchen, test each socket methodically from the consumer unit.

1. Read the manufacturer's instructions first

Before ordering anything, find the wiring section of the hood's installation manual. Some hoods come with a fixed 13A plug and are simply intended to go into a socket. Others have a short length of flex with bare conductors that must connect to a fused connection unit or junction box. A few higher-spec hoods specify a dedicated 16A supply, in which case call an electrician to run a new radial circuit.

Note the rated power in watts. Most domestic hoods run at 100–250 W. A high-power induction hob's matching hood may draw more. The rated power tells you whether a 3A fuse (correct for most) or a 5A fuse (for higher-draw models) is appropriate.

2. Isolate the kitchen ring

Switch off the kitchen ring main MCB at the consumer unit. Test with a voltage indicator at the socket closest to where the FCU will go. Confirm dead on both live and neutral pins before touching any wiring.

3. Choose where to fit the FCU

A switched, fused, double-pole FCU (also called a fused spur unit) gives the hood its own local isolation switch and fuse protection. Position it somewhere accessible — ideally on the kitchen wall between 150 mm and 450 mm above worktop height, within the same visual area as the hood but not hidden above the canopy. If you have a gas hob, keep the FCU outside the 150 mm flame-risk zone to each side.

If the kitchen already has a conveniently placed switched socket close to the hood position, it is perfectly acceptable to use that instead of a dedicated FCU, provided the hood manufacturer allows plug-in connection.

4. Take a spur from the ring to the FCU

Remove the nearest socket and identify the ring conductors (typically two sets of brown, blue and green-and-yellow cables). Connect a new spur by adding the spur cable conductors to the existing ring terminals at the socket: brown to L, blue to N, green-and-yellow to E. Run the spur in 2.5 mm² two-core and earth T&E to the FCU position.

At the FCU, connect the supply side terminals (marked Feed or In): brown to L, blue to N, green-and-yellow to E. Fit a 3A cartridge fuse in the fuse holder.

5. Run the load cable to the hood

From the load side of the FCU (marked Load or Out), run 1.0 mm² two-core and earth T&E to the hood connection point. Protect any surface run with surface trunking, or chase the cable into the wall and cover with plaster. Do not run unprotected cable behind plasterboard without marking the safe zone and confirming it follows one of the permitted routes under BS 7671 Appendix 1.

6. Connect the hood

Inside the hood's connection compartment (usually behind an access panel at the back of the canopy), you will find either a terminal block or the end of a flex. Connect brown to L, blue to N, green-and-yellow to E. Some hoods separate the motor circuit and the integral light with separate terminal pairs: the manufacturer's diagram will make this clear. Secure the cable entry with the cable clamp provided.

7. Restore power and test everything

Replace all covers and faceplates. Return to the consumer unit and switch the ring MCB back on. Switch the FCU on. Test all fan speeds and the integral light. Switch the FCU off and confirm the hood stops completely. Check that the earthed metal body of the hood does not register live with a voltage indicator.

Stop and call an electrician if: the hood specification calls for a dedicated circuit rather than an FCU spur, you cannot find the ring conductors and are unsure which cable is what, the FCU or ring MCB trips immediately when you restore power, there is any sign of burning or melted insulation in the existing wiring, or the hood body registers live after connection.

When to call us

Connecting a cooker hood to an existing FCU or socket is a reasonable homeowner job, provided the supply is already in the right place. The Part P line is crossed when a new cable run is needed from the consumer unit, or when you are unsure what the existing cables are doing. Both situations need a qualified electrician to carry out and certify the work.

Richard covers kitchen electrical work across Sandwich and the surrounding area in east Kent.

Need kitchen electrics sorted in Sandwich?

From a single FCU to a full kitchen rewire, Richard can quote for the work and provide the Part P certification on completion.

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How to wire a kitchen cooker hood