New Bathroom Extractor Fan - Wiring Query

[Colin47]

I presume that where you have mounted the new extractor renders the existing cable too short (hence the need for a junction box) which would be perfectly acceptable providing the existing cpc is maintained into the fan assembly (which of course will not used but should still have earth continuity within the cable) and confirmed during testing/certification.

You mention running a new cable to the light? which would indicate no isolator. I would recommend installing an isolator switch whilst upgrading the fan.

The junction box actually has 4 ports for cables 4xL1 4xL2 etc. This allows for various termination scenarios and not just a straight cable one in one out junction.

Yes this is correct. Currently the cable runs from bathroom light ceiling to extractor fan. The new inline Manrose extractor fan is in the loft. So a new cable run required from existing cable feeding the current extractor fan to new fan in loft using 3 core and earth cable via a terminal box is what the electrician advised.

There no earth in the wires feeding into the ceiling light so not sure why the previous electrican took this out. Would there be a valid reason why this earth might be taken out? We have had no issues with it so far.

The hager 4 terminal box - the 3 core and earth has bare earth cable - as this won't be used it can be stripped and terminated in the 2nd port of L2 ? or left as is ?

 

[DefyG]

There no earth in the wires feeding into the ceiling light

Are you sure and they haven't been perhaps cut short? Doesn't sound like you'll have integrity of the earth connection throughout, not just the bathroom light which depending upon light fitting (ie class 1) in a bathroom would give cause for concern!

 

[Colin47]

Are you sure and they haven't been perhaps cut short? Doesn't sound like you'll have integrity of the earth connection throughout, not just the bathroom light which depending upon light fitting (ie class 1) in a bathroom would give cause for concern!

The reason the earth was removed is because the current fan and the new fan does not require earth. The current fan there is no earth terminal block on the fan which is why I guess he removed it. The new Manrose MF100T inline fan has no earth terminal connection either. In the instruction leaflet it says no earth required because the fan is class 2 insulated appliance.

 

[DefyG]

The new Manrose MF100T inline fan has no earth terminal connection either. In the instruction leaflet it says no earth required because the fan is class 2 insulated appliance.

I'm familiar with many domestic extractor fans which are primarily class 2 (double insulated) and consequently are not required to be earthed. Often the earth conductor is sleeved and terminated in a terminal block/wago etc. within the fan enclosure.
That doesn't mean that the cable supplying it shouldn't have an earth conductor within it though and my point was that if the earth conductors had been removed from the light fitting (your post #11) you might not have earth continuity throughout the lighting circuit.