I am going to install an extractor fan in the bathroom. From what i have read, they are usually wired to the light switch, but what i would like advice on is can i wire the fan to the existing pull cord shower switch. Thanks.
The bathroom fan is only wired to light switch when either it's an extra and not required by building regs or there are no windows in the bathroom.
The simple method is a pneumatic push button which is pushed manually to activate fan. By swapping the light switch for a double pole switch you can have both push button and lights work the fan.
To take a supply from a ring circuit or any other circuit with high power you would also need a fused connection unit (FCU) to fuse down to 3 or 5 amps. It is common for a fan to go faulty so it is always a good idea to have some way to isolate it. Last thing you want is no lights because fan is faulty.
There are loads of regulations covering the fitting of a fan Part P, F, and maybe more. Any air pumped outside must be replaced and you don't want it being replaced with flue gasses so there needs to be a way for air to replace it.
Since it is notifiable work to DIY is an expensive option and far cheaper to get a scheme member electrician to do the work. This also means he does need to follow the rules. In most new houses the fan is fitted the building inspector passes the work then it is switched off never to be used again.
Hi. Two points here, first all work in bathrooms is notifiable to LABC so not DIY legal! second the fan is connected at the light fitting not the switch as there is no neutral at the light switch. It would be possible for a registered electrician to take a supply from the shower switch via an unswitched fused spur/fused connection unit fitted outside the bathroom zones, but again notifiable work. regards sparx.
Near every electrical job done by a DIY guy breaks the law. You should following Part P inspect and test all work which needs £750 worth of test equipment.
Like driving a car in 30 limit both 31 mph and 50 mph both break the law. At 31 mph likely you will get away with it. At 50 mph high chance of getting caught. You would never tell another motorist at what point you can take it and neither can we tell you of how far you can go in breaking the Part P law. This is up to you and it is unfair to ask other by how much you should break the law.
There are all sorts of excuses used. But they are just excuses.