Bathroom extractor fan help

[chris.wiss]

I'm replacing the extractor fan in my bathroom. The previous fan had it's own pull cord, the new fan is a timer model I want to run off the light.

The old fan was running from a spur off a power socket ring main via a FCU.
The bathroom light is running from a spur off the lighting ring.

The plan was to take the FCU off the ring main, and then connect the FCU via the light.

I assume I have to take the FCU off the ring main, otherwise there will be 2 rings connected to the same FCU.
Can I run the light and fan off the same lighting spur?

Thanks

 

[mhar]

Lighting circuit should be radial.
Must NOT connect lighting circuit to ring main in any way.
If circuit protected by a 6A MCB there would be no discrimination with a 3A fcu.
Only a student with a lot to learn so shouldn't really be replying but this is quite basic

 

[Dan23584]

If you are unsure on something this basic then I recommend you contact a registered electrician and get them to do this work for you.

 

[i=p/u]

well for the timer model, all you need is a switched live from light in bathroom and a perm live that runs the fan after light has gone off............. welcome along annd dont for get neutral and earth and safe isolation and zs test

 

[telectrix]

and whatever circuit you wire the fan into must be RCD protected.

 

[trev]

Don't forget the dreaded part P notification since you're extending a circuit in a special location

 

[telectrix]

Lighting circuit should be radial.
Must NOT connect lighting circuit to ring main in any way.
If circuit protected by a 6A MCB there would be no discrimination with a 3A fcu.
Only a student with a lot to learn so shouldn't really be replying but this is quite basic

problem here is that the fan manufacturer may stipulate a 3A fuse. therefore, you have to fit a 3A FCU,

 

[trev]

Unless you're in scotland of course

 

[i=p/u]

what code would it be if lighting circuit wasnt on rcd in bathroom

 

[i=p/u]

code 4???

 

[hillbillie]

Code 4 if it is an older installation and conformed to regs at the time. If it was put in last week, well, it shouldn't have been! But I would put that down as a code 2.

 

[Dan23584]

code 4???

I would put code 4 mate.

 

[johnelectrical]

problem here is that the fan manufacturer may stipulate a 3A fuse. therefore, you have to fit a 3A FCU,

anybody know a manufacturer who makes a three pole isolator (Needed to isolate the permenant feed, switched feed and Neutral) with 3a fuses for both the line and switch feeds?

 

[Octopus]

problem here is that the fan manufacturer may stipulate a 3A fuse. therefore, you have to fit a 3A FCU,

anybody know a manufacturer who makes a three pole isolator (Needed to isolate the permenant feed, switched feed and Neutral) with 3a fuses for both the line and switch feeds?

In one word no. The way to achieve the necessary "fuse down" to 3A is to "divert" the lighting circuit through a FCU before the light and do all the necessary connections for switch and fan after it.

 

[telectrix]

and then find that, in the event of a fault, that the 6A MCB will trip before the 3A fuse blows. Pointless.