Growning CFL use

[Rickbro]

Since incadescent bulbs in the near future are not going to be produced, where today is it safe to use a CFL? Since people are asking more for them and replacing incadescent bulbs in their existing luminares. I installed a fixture the other week and it stated NO CFLs use incadescent bulbs only. They have regular bulbs and floods that are CFLs now.... - is there a concern to put a CFL in any type of fixture. I heard of a case where one was put in a recessed light and it was left on all night - caught fire. Looking for a safe approach.
Thank you Rick

 

[tallgirl]

The only application I can think of off the top of my head is any fixture or circuit that is electronically switched.

There are issues with some fixtures where they were designed for more traditionally shaped bulbs -- PARs being my fave -- and the odd shape of the CLF base doesn't work.

 

[jmellc]

I'm wondering too, about heat issues. Haven't seen it addressed much, but the CFL's I've seen don't seem to heat up much. Wonder if any chart exists, such as fixture labeled for a 60 w bulb, could use up to xx w CFL.

 

[broadgage]

CFLs produce a lot more light for a given wattage input, or put another way they produce much less heat for a given light output.

If a fixture is listed for a 60 watt incandescent, then the FIXTURE should not come to any harm from a 60 watt CFL, since the heat output is similar.
It is unlikely though that the LAMP would survive for long in an enclosed fixture since CFLs are killed by heat.
In practice though a 60 watt CFL is a very large one with a light output similar to 250 watts incandescent, it wont fit in any common fixture intended for 60 watt incandescents.

For enclosed fixtures I find that a CFL of a wattage not exceeding about one third of the incandescent wattage to be a good rule of thumb.
Fixture listed for up to 60 watt incandescent, use a CFL up to 20 watts, which will still be brighter than the incandescent.

For fixtures that are open at the top, with only the lower part of the bulb enclosed by a shade, then there should be no heat build up, and a CFL may be the same wattage as the incandescent. In practice though a 60 watt CFL would look daft in most fittings intended for 60 watt incandescent, nothing unsafe if well ventilated.

Inferior CFLs sometimes catch fire and could ignite surroundings, reputable ones are made of non-flammable materials and incoroporate a thermal fuse.

 

[tallgirl]

The issue isn't exactly the heat, as in, "makes stuff get hot", but that a CFL is solid state electronics and they don't like heat.

I've saved every CFL I've bought since about February '07 and looked at how they fail, and where they were. Bulbs that point down wind up with darkened "tops" and often have burned / melted plastic around where the tube exits the "top" of the bulb. When they are upside down the "top" is now the bottom and the heat can't just go away.