Bathroom Ceiling Light Replacement

Manufacturers instructions should always be complied with, sounds like your wiring system is to 16th. edition, nothing wrong with that and that would have been correct 10 years ago. I think you'll probably require a class 2 rated light unit in this situation, (or selv) which would probably not stipulate rcd protection.

 

Whilst I agree that manufacturer's instructions trump everything they weaken their case by adding "according to IEE regulations". If all the main and supplementary bonding is in place then additional protection by an RCD is not mandatory. So if the fitting is suitable for the environment and zone (if it's in one) then I'd say you can fit this light.

 

I guess the manufacturer is covering itself should the light be "new" rather than a replacement.

 

To comply with the 17th edition regs all circuits in a bathroom must be protected by rcd, if the wiring is 10 yrs old you could most likely have an rcbo fitted in the consumer unit providing the required protection.

Alternatively you could feed just the bathroom lights with an rcd spur although the cost is similar to the rcbo.

There is no requirement to update to latest regs but if we never upgraded we would all still have lead cables and appliances plugged into sockets dangling from ceiling lights!

When you have just got out the shower and stretch up to dry yourself off, a belt off the light would be a bad thing, it's unlikely if it's all installed properly but for the sake of a few quid it's worth it. As the other posters have said manufacturers instructions must be followed.