Most CFL light bulbs are intended to last for up to 10,000 hours assuming ideal conditions - this means that the bulb comes on, has a chance to warm up, and then stays on for 3 hours.
The certification standard of 10,000 hours, or 3,333 uses - is based on the standard of 3 hours per use!
Starting a CFL puts stress on the lamp because you are applying a high voltage to the tube to “excite” the phosphorous and Amalgem inside the tube….this is what creats the light. The more you do this the more you wear down the tube.
A home night light is an excellent application for a CFL - it automatically turns on as it gets dark, and then off when it gets light - once per day. Assuming 8 hours each day, such a CFL would last 1,250 days or 3.42 years!
A CFL will not do well if it is turned on more then 5 times a day. If you are expecting to be turning the light on and off frequently, expect that the life of your CFL will be reduced by 30% or so. This is not a problem for most people because the bulb will still save money over this reduced life, versus non energy efficient incandescent lighting, but you should know about it.
Do not use the wrong style of bulb for an application, in particular recessed cans. If you use a high wattage spiral cfl bulb in a recessed you will see a greatly reduced life on that bulb - the excess heat will KILL your CFL bulb. The heat effect the electronics inside the integrated ballast and reduces the life of these by 50% or more!
Reflector CFL bulbs are built for recessed can applications. The “reflective” surface inside the bulb actually reflects the light (and hence a portion of the heat) down and away from the recessed can. This creates the perception of having more light in the room and dissipates the excess heat. The wrong style of CFL gives off MUCH LESS light (no reflecting) and will soon burn out from the excess heat.
Higher wattage incandescence's are not effected by this heat, for instance a 60 watt or 75 watt incandescent bulb can be put into a recessed can. Incandescent bulbs don’t ship with an integrated ballast. There are NO electronics to fry inside an incandescent bulb!
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