Installing an airvent A4HP extractor fan in bathroom

7 Mar 2006
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United Kingdom

I've just purchased the above fan (timer, humidistat and pullcord) and am a bit confused about how to install

1) The wiring diagram shows a 1amp fuse in the live supply wire only

2) My bathroom lights are halogen on a dimmer, wired on a JB circuit i.e no ceiling rose

3) What I want to achieve is for the fan to become operational when the light is switched on, with an isolator for the fan located above the bathroom door (externally). I do not wish to use the pullcord to operate the fan at all. There is a three terminal connector block inside the fan, terminals are L, N and LS

Any help on how to wire this up would be appreciated

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Not sure about your model, but most humidistat fans with pullcords work with the light coming on or humidity above a certian level.
The pullcord on the fan is usually a boost.

Surely the instructions explain all this?

Instructions state 'for wiring with a remote switch when the pull cord should be switched to the automatic position, (indicator off), and the cord cut off.'

1) There is no indicator

2) 'The pull cord or remote switch will switch between automatic humidity control and manual override. There is no permanent OFF position.'

Am confused about the 1amp fuse bit and how best to wire into my lighting system.
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The 1 amp fuse bit is for when you are using an FCU from (say) a ring final circuit.

You can connect into the lighting circuit and remove the pullcord per the instructions. You'll have 3 core & earth from your isolator?
Connect per instructions Live (L) Neutral (N) and Switched live (LS)

As this is in bathroom I hope you notified building control before starting work?

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