This switch is designed to dim incandescent lamps. It has nothing in its description about being used with CFL (compact fluorescent lamps) types. If you are attempting to dim standard CFL types, it will not work.
CFL's are available in both dim-able and standard types. As you may have guessed, only those marked as "dim-able" will work with a dimmer switch. Dim-able CFLs cost slightly more than standard CFLs but may be controlled by any switch. Dimmer switches may only control incandescent and other type lamps that
specifically state they are compatible with dimmer switches.
If you are attempting to dim incandescent lamps, make sure that you are not trying to dim lamps with a total wattage greater than the dimmer can handle. Most dimmer switches are rated for 600 watts, if you have two dimmer switches under one wall plate, the wattage rating drops to about 500 watts. This de-rating is because of the heat the switches create. There are dimmer switches that can dim more than 600 watts, but the price skyrockets for a
1000 watt dimmer, and keeps climbing.
If your wattage is within the limits of the dimmer, check the bulbs. If they are ok, the dimmer may have failed and require replacement.
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