I have an interior bathroom with no windows. In the ceiling is a NuTone 763RLN exhaust fan with light bulb fixture.

This unit was built in 2003, so the only light bulb specification provided is "100 watts (max) [incandescent]". However, the light emitted from a 100 watt incandescent bulb is very yellow for a bathroom with no windows. I would like to find a solution that produces a "neutral white" (~3500K) light that is at least as bright as a 100 watt incandescent (1200-1600 lumens).

My concern is, of course, that a CFL or LED bulb is going to die quickly in an enclosed fixture that vibrates.

How do I find a solution to this?

I have already replaced the plastic lens that came with the exhaust fan. The original, 13-year-old lens had yellowed. The new lens improves the light quality, but not enough. (I'm trying to avoid repainting the bathroom before putting the home on the market.)

I have already tried a low-wattage CFL that is designed for enclosed fixtures. In this category, I have only found low output bulbs (800 lumens). This is not enough to be an improvement.

Basically I am wondering if there are ways to mitigate the heat build-up and vibration in this environment. Or I'm looking for assurance that a certain type of bulb will last longer, under these conditions, than I am led to believe by the bulb documentation.

Alternatively, perhaps I could find an even better type of lens to cover the bulb enclosure. The new one that I just purchased is translucent, color-neutral plastic. Perhaps somebody makes a compatible lens that transmits the light of an incandescent 100 watt bulb in a more pleasing way.

  • 2
    LED bulbs don't care much about vibration (unless they are total junk.) Heat build-up is much more of a problem for them. Personally I'd look into non-bulb-based LED fixtures (separate from the fan) as the whole "bulb" business makes massive compromises from good LED fixture design (which should be optimized to get rid of heat.)
    – Ecnerwal
    Feb 28, 2016 at 17:01
  • If you are listing the house what is the problem with using a 23-26 watt CFL? Feb 28, 2016 at 19:48
  • @SpeedyPetey It seems dishonest to install something that won't last, right before selling.
    – Jacob
    Feb 28, 2016 at 19:53
  • @Jacob, dishonest? A light bulb? Then just put a 100 watt A-lamp in that will almost certainly last about 1/6 the time. I have never had any long term issues using a CFL in a bath fan. Feb 28, 2016 at 19:56
  • @Ecnerwal Perhaps I could find a type of LED "rope of lights" that I could plug into the E26 socket inside the exhaust fan fixture. It seems challenging to find or customize something that would look good enough to use while selling the home.
    – Jacob
    Feb 28, 2016 at 19:56

1 Answer 1


You need a Daylight, Natural Light or Full Spectrum Bulb, going to Cool White is only a slight improvement & may be what you have now (Soft White & Cool White color is 2500K to 3000K). You'll need to check the package's or box's stated ratings, listing the color as 4500K up to 6500K.

GE & Phillips have a single incandescent option, though the CFL's have a wider offering. This is an enclosed fixture & not a sealed fixture so either of these will & do work perfectly fine, LED's will not. However, overall bulb length may be limited by the fixture & incandescent may be your only choice.

  • Can you please add more information – or reference – for the statement "LEDs will not"? Feb 29, 2016 at 11:31
  • 1
    Yep. Most if not all LED bulbs are not rated for enclosed fixtures because they require a lot of ventilation for heat dissipation, the bulb boxes do also directly state this as well. Without that ventilation for heat dissipation the LED bulbs will die very-very-very prematurely. You'll also see bulbs with heat-sink fin structures as a very prominent feature. Now, an LED "FIXTURE" is no problem at all, as it's designed with either heat dissipation &/or ventilation in mind & may only appear to be enclosed or even be actually sealed.
    – Iggy
    Feb 29, 2016 at 14:17
  • 1
    The key point here, from SpeedyPetey and Iggy is that the exhaust fan is an enclosed fixture, not a sealed fixture. So I won't be as worried about heat build-up damaging CFLs prematurely. Thanks.
    – Jacob
    Mar 1, 2016 at 2:47
  • Yep, all of my ceiling enclosed dome fixtures of 2 & 3 bulbs have had CFL's for a decade & all live to their full extent without issue. Plus, you have a fan evacuating & heat-sinking for a boosted dissipation. If the CFL fits, it'll be good for years & years.
    – Iggy
    Mar 1, 2016 at 3:11
  • 1
    The bulbs I chose are CFLs that emits 1200 lumens with 4100K color. One bulb per fixture. With an updated lens cover (not the old yellowed one) this produces very attractive illumination for bathrooms with no windows.
    – Jacob
    Mar 10, 2016 at 20:12

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