How to wire up a cooker hood correctly

[600rob]

In my girlfreinds flat she has and cooker hood that has never worked properly

The flat and all the cooker hood were installed and owned from new.
There seems to be some power going to it as the lights work as do the lights on the instument panel which come on when you try to operate the fan.

the problem is that the fan has never worked, there is just a very faint noise when you switch the fan on but the motor does not spin up

I decided to take this off the wall this morning and inspect it. nothing blocking the fan/motor so i can only assume its and electrical problem.
the hood has now been removed from the wall.
and ive observed the following. there are 2 cables coming from the unit.

one grey outer with 3 wires: an earth, live and neutral (green/yellow, brown & blue), the other is a black cable with just two wires: a live and neutral (brown & blue)

i connected both of these up to separate 13a plugs and tested them... the former opertates the lights and control panel. the other does nothing.... both together blew the fuse on the live and netral cable!

When the hood was installed it was wired to a 4 way block.
connected to the block is a live neutral and a earth which go to a non swicthed FCU. There is an additional live neural and earth which i think go to the main fusebox or main circuit for the house, also coming from the main circuit is a single yellow wire which is connected to the last part of the block.

when it was all connected up the earth, live and neutral on the grey cable coming from the hood were connected up to the corresponding connections on the block.

both the blue and the brown wires coming from the black cable on the hood both connected up to that single yellow cable coming from the mains circuit.

can anyone tell me how if this sounds correct and what the single yellow cable would be for? also how would i correctly wire this up with the connections that i have

ive looked all around and inside the hood and there seems to be no markings, model number or anything to identify it. and typicaly the misses has thrown out the instuction manual!

Many thanks
rob

 

[PrenticeBoyofDerry]

can we have a picture of unit and cables.
Was there anything else connected to the extractor?

 

[600rob]

here we go.....


this is the hood:

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03187.jpg

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03188.jpg


in this pic you can see the two cables coming out from the unit

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03189.jpg


this one shows the wire i beleive to be coming from the mains and out to the FCU. (this is where the wires from the unit were connected to)

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03190.jpg

 

[PrenticeBoyofDerry]

To me that looks like the grey cable from the hood has been added on to feed something else maybe cabinet lights, gas cooker ignition......
So remove that for now and use the black flex to connect to your supply side.

I assume the grey twin and earth is the supply feed.
what is the fuse rating for hood and what rating is being fed via the supply cable? Should be something like 5 Amps.

Check for loose cable inside the hood prior to energizing and is there any other fuses within the wiring in the hood. check they are okay or replace.

Then connect,
blue to blue (neutrals)
Brown to Brown (lives)
That should give us power to the motors.

What is the white cable doing feeding an FCU for what?
Colours are not standard

 

[600rob]

To me that looks like the grey cable from the hood has been added on to feed something else maybe cabinet lights, gas cooker ignition......
So remove that for now and use the black flex to connect to your supply side.

I assume the grey twin and earth is the supply feed.
what is the fuse rating for hood and what rating is being fed via the supply cable? Should be something like 5 Amps.

Check for loose cable inside the hood prior to energizing and is there any other fuses within the wiring in the hood. check they are okay or replace.

Then connect,
blue to blue (neutrals)
Brown to Brown (lives)
That should give us power to the motors.

What is the white cable doing feeding an FCU for what?
Colours are not standard

thanks for the reply mate.

at the moment the grey cable from the hood seems to be the only one giving me any power (lights/instrument panel). the black one is not giving me anything.

the cables in the last pic go through the wall and into a cupboard where the main fuse box is located and a load of switched fcu's that are labeled to indicate which kitchen appliances they are for (the only one that is not switched is the one for the hood,) all of these have 13a fuses.

From what i can make out the grey cable is going through the wall to the fcu and the white is heading in the direction of the main fuse box so im assuming it goes to the main circuit of fuse box

i tried wiring the black cable that comes direct from the hood and into a 13a plug and tried this in a wall socket...nothing worked.

i did the same with the grey wire coming from the unit and this seemed to power up the lights and instrument panel

i cant see any other fuses inside the hood, but i will have a good look inside and see if i can find any loos connections or anything else


Ill try removing this grey and connecting the black one as you say. buy the way this has no earth...just an live and neural...will this be okay?

p.s what are you referring to when you say supply....mains power circuit?
(sorry im an amateur hence not so good with the terminology!)

 

[PrenticeBoyofDerry]

Supply=the electrical feed to the hood(what is giving you the power supply) but this seems to be the white cable which does not look like standard core colours.
You say the black flex does not power the hood up!
But it looks to me that this should be the cable that belongs to the hood, but may not, even though no earth wire within the cable if the appliance is double insulated it will be safe, this will be denoted by a symbol that looks like a square inside a square and should be found on the hood.
How old is the hood?
Do you know who/when it was fitted?
Have you tried to turn the fan manually (with the power off) could be seized/jammed.
Picture of where cables go inside any chance?

 

[600rob]

okay ive managed to get inside the hood and check it out.

the wiring has been messed about with and from that i can work out it seems that the black cable has been added.

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03193.jpg

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03192.jpg

in these pics you can see the upturned part of the hood which houses the lights and the black unit which is some sort of control box wired to the operation buttons.

all of this is connected to the main wiring with the large black white connector that can be seen in the pic.

if you look at the fan/motor you can see a smaller connector plug and socket. these were disconnected when i opened the unit.
On the female side of this connector one of the wires (black) had been cut.
the cut wire is joined onto a one way block which has both the blue and brown wires from the added black cable that comes out from the top of the hood.

you can see the cut wire in this pic

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03191.jpg

the grey wire coming into the three way block looks like it is supposed to be there as there is a proper mounting point for it and the live earth and neutral markings are on the fan casing showing where to wire. this can be seen in the above pic

my though is to do away with the added black cable, re-connect the black wires that were cut join the connector plug and see if that works?

any thoughts?

 

[PrenticeBoyofDerry]

Right looks like there has been some tampering.
As cut wire and cable grips as missing too.
Now from what I can see, your prognosis is a fair assumption.
The connector(male/female) look like they belong to the fan and together.
God knows what that's about, snipped black wire connected up with both cores(blue and brown) in black pvc cable
Anyway reconnect the black cut cable and snap the male and female back together.
We now can be happy that the grey pvc cable supplys the power.
Then we need to address the connection outside the hood, could do with that in a choc bloc for safety reasons.
But lets get the thing working that's providing it's not knacked.

 

[600rob]

right ive reconnected everything up as it should have been and i now have power anf the unit is fully functioning.

now to wire it into the mains

as mentioned in an earlier thread this is what is currently coming out of the wall

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03190.jpg


still confused as to what that single yellow wire connected to the block is for?

but shall i try connecting my live earth and netral from the fan straight onto the other side of this block anyway and see what happens?

 

[PrenticeBoyofDerry]

brown is live
blue is neutral
green yellow is earth
on the grey cables
link for you get a choc box to protect from danger or use a junction box for the joint.

http://www.chocbox.info/

 

[600rob]

hi there,

ive wired it all in as shown in the pic here

http://s919.photobucket.com/albums/ad31/r_o_b_b_y/?action=view&current=DSC03196.jpg

everything seems to work fine on when its wired up like this.

the last thing i need to do now is get one of those choc boxes to house the block and ill be all done,

many thanks for posting that link for the choc box and also for the help and advice.

regards

Rob

 

[PrenticeBoyofDerry]

no worries pal