On Thu, 27 Jan 2011 04:25:32 +0000 (UTC), (Don
Klipstein) wrote:

In ,
wrote:

On Wed, 26 Jan 2011 22:48:57 +0000 (UTC), (Don
Klipstein) wrote:

In , wrote:
On 25 Jan '11 22:20:13 0 UTC, (Don Klipstein) wrote:

My experience is on average around 4,000 hours. This includes ones that
get some extra heating by being in an enclosed fixture. (I only use 13
watt ones there to keep the extra heating down.)

You are getting almost 4 times my (average)cfl lifespan. And I'm
using the bulbs made for the specific use (in this case PAR type
reflector floods in pot-lights)

Pot lights are heat hellholes. CFLs easily overheat in those. Try a
different brand, a brand overtly rated in writing for such use, one with a
specific and high maximum ambient temperature rating, or a lower wattage.

SNIP my bit on what is used in commercial buildings

I'm currently running the third "brand" of PAR type cfl - and all PAR
type bulbs are supposed to be made for this same type of service.
It says on the bulb "not for use with dimmers or in totally enclosed
recessed fixtures"

These are not totally enclosed - and if the slowness in lighting is
due to "warm-up" these things should light FASTER, not slower.

One question what is the wattage of these CFLs?

I thought I had stated they are 15 watt units After an hour of use
they are not uncomfortable to remove, but the socket end is getting
uncomfortable to hold.

The highest temperature I can register with my I/R temperature guage
is 117F after an hour of on-time. It stabilizes there.
Also, I do see "PAR" CFLs that appear to me not up to working OK in
the "heat hellholes" they appear to be made for. I see ones either
lacking a written statement that they are OK there, or having being OK
there qualified by a specific ambient temperature limit that sounds to me
easy to exceed in "heat hellhole" recessed ceilingt fixtures.

If the fixtures are open at the bottom, CFLs can still easily overheat
in them. Hot air likes to move upward. In an open-at-the-bottom
recessed ceiling fixture, the hot air won't move much - so the lightbulb
in such a fixture easily bakes up the temperature of the air in the
fixture.

As for heat confinement speeding up warmup: My experience is that this
does not increase rate of warmup, so much as increasing how much the
warmup progresses (such as past optimum temperature). Do please keep in
mind that "PAR" CFLs tend to be ones with outer bulbs, and those tend to
start dimmer and need more warmup time than CFLs without outer bulbs.