Gear-obsessed editors choose every product we review. We may earn money if you buy from a link. How we test gear. The complex circuitry in these new bulbs makes them difficult to dim. In many cases, a typical dimmer switch (now called a legacy dimmer in the electrical industry) won’t work properly, if at all, with CFL or LED bulbs. Legacy dimmers were designed to work with incandescents, and CFL and LED bulbs bear no electrical resemblance to these types of bulbs. Comparing them is like equating an electric heating element and a television set. Both use electricity and both give off light, but that’s where the similarity ends. The solution is to buy a dimmer switch rated for both CFL and LED bulbs. Two reputable manufacturers of CFL/LED dimmers are Leviton and Lutron; both provide lists of bulbs they’ve verified will work with their dimmers. Next, buy dimmable CFL and LED bulbs that you know will function with your switch. Though these bulbs may also work with the older legacy dimmers, it’s likely you’ll experience some of the problems you mentioned. It’s worth noting that in 2011 the National Electrical Code was changed specifically to requi...