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The switch includes a standard-looking rheostat; I have read the issues around using dimmer switches with conventional CFSs. I don't value the "dimmer" function on the hood -- just want to see the food that is cooking when the room is not well lit.

Am I okay to put a CFL in here as long as I switch the light all the way on or off? If i get an LED bulb, is this sufficiently "resistive"? I am guessing not...

Thanks for any help. Sorry if this is insufficiently technical. Amazed to find zero hits on "incandescent or resistive 120V AC Only" which is literally on the switch inside this hood (purchased 2003).

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    \$\begingroup\$ It's likely to get hot under a range hood. CFLs and LEDs don't like being hot. Incandescents stay hot all day & all night. Stick with the incandescent as the label recommends. \$\endgroup\$ – brhans Dec 3 '16 at 13:58
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CFL and LED bulbs contain circuitry that make them appear relatively resistive even though they contain inductive and capacitive elements. The warning is mostly against highly inductive loads since they can result in excessive amounts of current flowing through the circuit when the switch is opened.

But regardless, you should only ever use dimmable bulbs in a dimmer circuit, even if you will never use it at anything other than full on or full off; non-dimmable CFL and LED bulbs may not react well to the transient waveform while switching between them, and even "all the way on" can still have some undesired distortion.

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I would not connect a LED bulb to this lamp.

The reason is the following one:

You say: "The switch contains a standard-looking rheostat". You are not 100% sure that it is a thyristor-based circuit (also containing a rheostat) as it is used in most trimmers.

In this case you could not guarantee that the voltage at the bulb is really a sine wave. Many LED bulbs only work correctly if the voltage is a sine wave.

In the worst case you'll have fire in your apartment!

By the way: Just having a rheostat in series to the LED bulb may even be worse:

Many electronic devices are constant-power sinks which means that the current (in the case of AC: the effective current) rises when the voltage drops. This is exactly the opposite of a resistive load.

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