"David W.E. Roberts" wrote:
Thank you for the comprehensive information.

I had better check what bulb is in the light.

The one you changed to - is it a normal 'wall box' timer as advertised in
the national press :-)
Will it work with a two way switch?
I have one switch in the hall and one in the garage.

Greenbrook T23H
http://www.greenbrook.co.uk/pdf/T23H.pdf for instructions

I don't think it does two-way switching I'm afraid.
I couldn't get my head around two-way switching
with a timer anyway - thought about it for ages and
couldn't see how it would work. My inclination would
be to have a timer on the supply to the circuit, and use
normal two-way switches, but even this wouldn't
guarantee the correct outcome, only that the lights
could only be on at certain times.

Al


Cheers
Dave R