The new mercury bulbs & recessed fixtures?

Question

The package on my energy efficient bulbs advises not to use in recessed fixtures. since they produce less heat i had assumed they were better than incandescent bulbs for that.

why cant they be used in recessed fixtures?

if i use them anyway is it a fire hazard or will it just cause premature bulb failure ?

Answer 1

Incandescent lamps (for recessed fittings) usually have a reflector to direct the heat away from the fitting, energy efficient ones don't so the heat could build up around the lamp.

I don't know whether this would be a fire hazard but it couldn't be a good thing.

Answer 2

I talked to the product manager in charge of CFL (compact fluorescent) bulbs at a major lighting company. Excess heat can damage the electronic circuitry in the ballast of the bulb (the ballast is in the bulged area between the glass and the bulb's base). This will dramatically reduce the life of a bulb. A recessed fixture tends to trap heat generated by the bulb, so that's why some packaging says not to use them in a recessed (flush with the wall or ceiling) fixture. Another restriction you'll sometimes see regards "enclosed" fixtures.  These are fixtures where the bulb is entirely covered with a glass globe or shade. Again, the restriction relates to overheating.

Some bulbs shouldn't be used in enclosed fixtures, some shouldn't be used in recessed fixtures, and some shouldn't be used in enclosed or recessed fixtures. Doesn't make life easy, does it? In any case, follow the recommendations on the bulb packaging and you'll be fine. If a bulb isn't rated for the kind of use you need it for, look for a different brand of bulb.

And when a CFL bulb is dead, be sure to dispose of it properly because the inside surfaces of the glass contain traces of mercury. Here's some information about recycling CFLs:

http://www.thisoldhouse.com/toh/article/...

Also,  Home Depot just launched a CFL bulb recycling program--details below.

Answer 3

If you want to use them in a recessed fixture purchase ones that are designed for recessed applications. They do make them in a number of sizes to fit most any recessed fixture. Also if your recessed fixtures are on a dimmer use the fluorescent that are dimmable.

Answer 4

I believe it will damage the electronics in the base of the bulb more than be a fire hazard.

I have used them and I have had them fail.