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(Don Klipstein) wrote in message ...
On 18 Dec 2003 01:08:40 -0800, (Fleemo) wrote:

I have a fluorescent light fixture in my bathroom that won't fully
light up anymore. When I flick the switch, the bulbs come on to about
30% full brightness. If I leave them on for a long time (maybe a half
an hour), they eventually kick on to full brightness. Obviously the
bulbs aren't burned out. What do I need to do in order to "see the
light?"

Does this have two 2-foot 1.5 inch diameter 20 watt bulbs? If so, then
chances are you have the usual "trigger start" ballast for that. I see
that dim performance, often with a little flickering, with those.

Replacing both bulbs usually fixes this.

Probably better would be to replace the ballast with one for two F17T8
"lamps" (bulbs), and then get two of those bulbs. You will probably need
to get all of this from an electrical or electrical/lighting supply shop.
Pay attention to the ballast wiring diagram on the label - it may
be different from from the wiring of the old ballast.

The F17T8 bulbs are available in different colors and two color
rendering grades. My favorite is GE /SPX35, Philips /TL835, or Sylvania
/D835 ("semi warm white" [my words] 3500 Kelvin, color rendering index in
the low-mid 80's).

- Don Klipstein )

I second earlier suggestions to replace both lamps and upgrade the
ballast to an electronic model. But in bathroom, due to relatively
frequent on/off cycles, lamps will fail relatively quickly on
so-called instant or rapid start electronic ballasts. For replacement
use only a programmed start el. ballast; pick brand name specifically
for the lamps you have. Good programmed start ballast should start
your lamps 30-40K times on average without any effects on the lamp
life vs. few thousands only with a rapid start ballast. The best
ballasts out there are able to do 500k (yes, half a milion!) on/off
cycles and lamps still look like new.

Jack