On Apr 23, 10:07*am, mm wrote:
A friend tells me that, The two fluorescent bulbs in the furnace room
were were doing what they do in old age. *After the electrician had
installed AC-connected smoke detectors, I saw that the light was
partially on even when switch off. *So I disconnected the fixture.

And he wants to either fix it by replacing parts or install a new one.

For once I know the project beforehand and can ask your advice
beforehand, since I certainly don't know what to do.

How can it be partially on when the switch is off? * How can
disconnecting the fixture be more effective in turning it off than
just flipping the switch?

It didn't used to be like this. * Certainly the new AC smoke detector
doesn't have a magnetic field strong enough to make this happen.

Advice?

Sounds like whoever installed the smoke detector may have connected it
to the switch wires for the light.

Jimmie