In article ,
Stephen writes:
Hello,

There's an 8' tube in the garage and when it is switched on it takes a
long time (tens of seconds) before the light comes on.

I thought that when tubes failed they blinked several times before
lighting. With this there is no flashing just darkness, darkness,
darkness, light.

The tube and starter have been here longer than we have, so that's at
least four years.

Do I need a new tube or starter or both?

8' tubes can be hard to start in the cold, but I don't think it's
got that cold yet. Given the tube does start eventually, and assuming
it doesn't have darkened (worn) tube ends, my money would be on the
starter having drifted out of spec, but it could still be either.
(The working spec for 8' starters is might tighter than for other tubes.)
It may well be that the electronic (fluoractor-based) starters such
as a Pulsestarter EFS 600 will work better with long tubes; I haven't
tried one on an 8' tube, but it claims it should work.

Secondly, are you sure it has a starter? A control gear type called
semi-resonant start was sometimes used with 5' - 8' tubes, and that
takes longer to start, but works more reliably in the cold. There
is no starter with semi-resonant start control gear.

Finally, check the fitting metalwork is earthed. That can make a big
difference to ease of starting with the long tubes.

--
Andrew Gabriel
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