Rob
Probably the fan. Take a note of the make and model if possible and pop along to your local DIY store and see what theyve got.
Now the two pairs of wires. One is a switch supply to start the fan and run it when you are in the bathroom and have the switch on. this pair probably has a red and black passing through the switch which would need to be what we call double pole i.e. it switches live and neutral. the other is the permanent feed and may loop from the live side of the switch and this powers the run-on timer in other words the 15 minute delay.
With a bit of luck your fan is at the end of the duct at the grill you see when you look up in your bathroom it should just screw out after youve disconnected the power at the fuseboard, don't forget one of these is live all the time - possibly fed from your neon lit switch outside but dont chance it without a proper test meter - the new fan should fit the tubung as its pretty standard, just check with the guys at the store before you buy or measure your tube to be certain. the wiring diagram will tell you where to put everything and how to set the run on time. check how the old one was wired to identify the two cable pairs at the fan end.
Kenny F
December 2008
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