cooker hood wiring

[tenorbel]

I am fitting a cooker hood and have thought of options for mains connection;-

1. switched fused connection unit actually on power ring
2. switched 13A socket actually on power ring
3. switched fused connection unit on spur from power ring
4. switched 13A socket on spur from power ring
5. switched fused connection unit on spur from input to cooker switch box, vertically above it
6. switched fused connection unit on spur from output of cooker switch box, vertically above it

My thoughts are that;-

1. requires 2 cables running high up the wall, is probably not allowable and a bit stupid
2. again requires 2 cables running up wall, would mean a power ring main socket would end up a foot below the ceiling and out of conventional ring main zone
3. is probably ok
4. is probably ok also, but requires a plug connection making it seem less dedicated
5. is it allowable?
6. ALL above have problem that the isolating switch is a high reach in an emergency, but this option doesn't, so it seems fine to me, but is it allowable?

I'd like to do 6., but if not allowable what is next best?

 

[ban-all-sheds]

My thoughts are that;-

1. requires 2 cables running high up the wall, is probably not allowable and a bit stupid

Why would it not be allowable to put an FCU on a socket circuit, and why would it be stupid to do so? And why put the FCU up high?

2. again requires 2 cables running up wall, would mean a power ring main socket would end up a foot below the ceiling and out of conventional ring main zone

Can you tell us where you've read about "conventional ring main zones"?

3. is probably ok

It is.

4. is probably ok also, but requires a plug connection making it seem less dedicated

So does (2).

5. is it allowable?

As long as the FCU terminals can accept the size of cable used for the cooker circuit and as long as the cooker switch terminals can accept 2 of them, and as long as you comply with the rules for concealed cables, yes.

6. ALL above have problem that the isolating switch is a high reach in an emergency, but this option doesn't, so it seems fine to me, but is it allowable?

Well ditto to (5) re allowable. But why would the FCU be lower than with (5)? Or indeed with any of the options?

 

[Simon35]

I have an FCU on the ring in the back of a kitchen base unit, up to a double pole switch above the worktop, then up and then across to a socket in the cooker hood chimney where the extractor plugs in.

I took the 3A fuse out of the cooker hood moulded plug and put it in the FCU, and put the 13A from the FCU in cooker hood plug for a bit of discrimination.

All cabling is within the zones created by FCU's, switches and sockets.

 

[tenorbel]

Thanks.

The cooker hood is one that sits behind a door and operated by pulling the door out towards you. My plan is to fit the cooker hood in the middle of a row of wall units and feed it from a connection point (switched 13A socket or SFCU) immediately above one of the adjacent units. In such position the connection point should not be that easily seen and still logically associated with the cooker hood it's controlling.

I like the idea of both cooker and hood being on the same circuit so that when needing to fully isolate anything to do with the cooker it's just the cooker circuit mcb that would require setting to off. My worry (lack of knowledge) is that supplying both hood and cooker from the switched output of the cooker switch box is in some way not allowable - if it is allowable then to me it's a no-brainer.

 

[EFLImpudence]

if it is allowable then to me it's a no-brainer.

It is allowed and I agree.

 

[ban-all-sheds]

All cabling is within the zones created by FCU's, switches and sockets.

I would disagree with that if you are relying on the hidden socket to create a horizontal zone for the cable to do a dog-leg into.

 

[ban-all-sheds]

It is allowed

as long as the cooker switch terminals can accept 2 (cables)

tenorbel - I can't visualise where all the cables will run - please take note of where you are allowed to put them, and the requirement for RCD protection of any new buried cable or sockets: //www.diynot.com/wiki/electrics:walls

 

[tenorbel]

I was't planning to fit a hidden socket.

The CCU is existing, so was planning to chase vertically up the wall from it to a point immediately above a wall unit and fit a SFCU. The cable would be from CCU output to SFCU in oval conduit buried in the chased channel. The cooker hood would connect directly in to the SFCU through the cable exit, with the majority of the cable hidden behind the cooker hood. Would all this be ok?

If so can I use 2.5 or 1.5 for the cable from CCU to SFCU?

 

[JohnW2]

I was't planning to fit a hidden socket.

You weren't, but that is seemingly what Simon35 has done ("...a socket in the cooker hood chimney").

Kind Regards, John

 

[Taylortwocities]

Of course, you could just power it from the lighting circuit.

 

[tenorbel]

No can do with lighting circuit - loft converted bungalow with chipboard flooring upstairs means impossible to get access to downstairs lighting circuit, short of attacking upstairs floor with crowbars!

Still favour the CCU plan.

 

[Simon35]

All cabling is within the zones created by FCU's, switches and sockets.

I would disagree with that if you are relying on the hidden socket to create a horizontal zone for the cable to do a dog-leg into.

No need to worry, it's within the 150mm safe zone at ceiling level.

Even if it wasn't I can't find anything in the regs to disallow what I've done.

 

[ban-all-sheds]

Even if it wasn't I can't find anything in the regs to disallow what I've done.

Skill, judgement, knowledge and belief, old bean.

The whole point is that an accessory creates a zone which (in theory) people know not to drill into because there could be cables there, running to/from the accessory.

If the accessory is not visible then neither is the zone.

 

[ban-all-sheds]

No can do with lighting circuit - loft converted bungalow with chipboard flooring upstairs means impossible to get access to downstairs lighting circuit, short of attacking upstairs floor with crowbars!

http://www.axminster.co.uk/armeg-solid-board-cutter-127mm

 

[Simon35]

Even if it wasn't I can't find anything in the regs to disallow what I've done.

Skill, judgement, knowledge and belief, old bean.

The whole point is that an accessory creates a zone which (in theory) people know not to drill into because there could be cables there, running to/from the accessory.

If the accessory is not visible then neither is the zone.

"If the accessory is not visible then neither is the zone." - in your opinion, not in regulation.