Replacing CFL with recessed LED

s/CFL/LED/g

8 min readMay 19, 2019

On moving in, we concluded that the smell, flickering, glare, and buzzing of CFLs (compact fluorescent lamps) in recessed sockets above our kitchen didn’t suit us.

On finally prying one of these eyesores from the ceiling, I discovered I couldn’t simply replace them with just any energy efficient LED.

Please skim the article, watch the clips, and prepare your tools before starting.

TURN OFF YOUR ELECTRICITY AT THE BREAKER BOX

Before proceeding.

One does not so easily banish government-mandated, four-pronged GX24Q-3.

IamDrCee’s YouTube video, “Superior Method for 4 Pin / G24 Socket CFL to LED Conversion with Ballast Bypass” guided me through my first retrofit.

Replacing a bayonet-style CFL requires bypassing the ballast that’s built into the junction box above each ceiling fixture. Pro-tip: Costco in SoCal has a quarterly sale during which these bulbs are half their normal price thanks to subsidies from the power companies. You’ll be limited to buying ten at a time, but the trips are well worth it.

I replaced my CFLs using LEDs from retrofit kits like this.

Tools for a successful retrofit

A good wire stripper — the green one in this picture below is the cheap one I bought, regretted deeply, and exchanged for a that Klein
Dust mask
Flashlight (I use battery-powered nightlights from B&M Costco instead)
Ladder
Safety glasses
Sharpie
Slotted (flathead) screwdriver with as small a head as possible (I bought a set and used the smallest one)
Stubby screwdriver (all my screws were Phillips)

Optionally:

Butcher, or similarly large sheet, paper on the floor to catch debris
Electrical tape (if you’re paranoid)
Gloves
Masking tape
Trash bags
Wire cutter (you can use your wire stripper, but a cutter sure is easier)

Don’t buy cheap stuff like I did with these pliers. They made my first retrofit miserable.

TURN OFF YOUR ELECTRICITY AT THE BREAKER BOX

Turn on the bulb you’re working on, turn off the electricity at the breaker, and then return to verify that the bulb you’re working on does not turn on.

I used masking tape and a cut-open trash bag to capture most of the drywall dust that fell.

Extract the CFL

Holding firmly by its base, pull down with all you’ve got.

Mine took so much effort to remove that I thought it couldn’t be done.

Avoid holding and yanking the glass. If your bulbs are old, they’ll exude an odor you’ll want out of the house ASAP. Home Depot entrances have bulb recycling bins where you can drop them off.

TURN OFF YOUR ELECTRICITY AT THE BREAKER BOX

This means when you flip the switch for the light you’re working on, it shouldn’t turn on. If you have any doubt, consult an electrician.

Remove the baffle

You’ll probably want your safety glasses and mask for this.

This is a great YouTube clip on how to do it since those torsion springs holding it in place can be tricky: https://www.youtube.com/watch?v=KS8rtP1ijjw

Cut the wires from the baffle

On top of the baffle will be four wires (two red and two blue) the lead from the baffle up into the can.

Cut all four wires evenly, ideally closer to the baffle itself.

Mark and unscrew the can

Draw a tiny line where the screws line up along the perimeter of the can housing. This will help you align the can correctly at reassembly.

Use a line, not a dot, because debris will fall from the perimeter, and your dot might, too.

Then unscrew the four Phillips screws holding the can in place.

Coax down the can

Each of mine required different angles of effort to pull down. Without the four screws, they stay up there by friction only.

Using a turning motion helps.

My downstairs cans were easily pulled down, but one of my upstairs ones was so stuck to the spray-on foam in my attic that I had to use a plier and the wire stripper (as a second plier) to pull it down.

Junction box

Using the tab at the top, open up your junction box to see a tangle of wires.

From your house, you will have: a hot wire (usually black); a neutral wire (usually white); a ground wire (usually green but may be barren).

From the junction box are two kinds of wires: incoming (leading into the ballast) and outgoing (away from the ballast). Incoming will be a black wire and a white wire. Outgoing will be two red and two blue wires.

There will be four wires (two red, two blue) coming into the junction box from a flexible conduit that connects the can to your junction box. The reds will be capped to the reds coming out of your junction box, and the blues with the blues.

Cut some wires

WEAR SAFETY GLASSES BEFORE CUTTING OR STRIPPING WIRES.

Cut wires according to the diagram below. Be careful not to cut everything at once, or pull too many wires in and out of the conduit, or you’re screwed. I suggest:

Cut one red pair where the two wires are capped, like in the picture above
Pull the wire out through the conduit
Repeat for one blue pair

You can bin the cap you cut off the wire.

Practice

Practicing cutting those extracted wires and stripping them.

Working on a junction box inside a little hole in the ceiling is difficult, and even after having done many retrofits, I find few practice runs helpful. There’s a specific angle and technique that works great for me, but it takes me a few tries to get back into the groove.

Bypass the ballast

In my junction box picture a few pictures ago, you see some rectangular objects that have black wires and white wires leading into a cream colored section, and a clear area attached above that. That’s a push-in connector. Stripped wires can be connected by plugging them into the push-in connector without needing to twist wires together, or cap them.

Your homebuilder might have chosen instead to twist wires and cap them off. I don’t have experience with those, so please consult several YouTube videos.

Remove ballast’s wires from the connector

From the ballast box you’ll see a white wire emerging and going into your push-in connector, or being twisted and capped along with a white (neutral) wire coming from your house.

Don’t remove more wires from the connector than you are going into the ballast in your junction box. Other wires may connect to other light fixtures.

Removed the neutral wire emerging from the ballast in the junction box, but left the *other wires in place.*

It is entirely possible to pull a wire out of a push-in connector and re-use it. Extract the ballast’s hot wire from the push-in connector sliding the slotted screw driver in with the wire (usually on the curved side of the connector) and while pushing in the screw driver, pull out the wire.

Repeat for the black (hot) wire. Once you’re done you’ll have something like the picture below. Tie together the vestigial wires coming out of the ballast box and move them out of the way. If you’re paranoid, use electrical tape.

It took me forever to remove wires from the first push-in connector, but then I got the hang of it.

WEAR SAFETY GLASSES BEFORE CUTTING OR STRIPPING WIRES.

It took me several practice attempts on another wire to get a clean strip here.

Strip conduit wires

Strip the remaining red wire emerging from the conduit and plug the red one with the black wire(s) in your junction box’s push-in connector. Red with black.

Repeat for blue, but plug this with the white wires in your junction box’s push-in connector. Blue with white.

Ensure the wires are pushed in all the way. A tiny bit of exposed metal at the top is okay fine as long as metal touches metal inside the push-in connector.

Repeat inside the can

Strip the wires emerging from the conduit into the can.

These aren’t quite as clean. I was sloppy.

Remove connector

LED kits come with an adapter to connect your LED to a traditional screw-in bulb. Carefully remove the connector from the stranded black and white wires.

Slide the slotted screwdriver between the wire and the metal plate pinning the wire, and pull gently (but firmly) to remove the wire without shredding it.

Attach connector

These connectors aren’t clear, so ensure the red and blue wires are stripped similarly to the stranded black and white wires that came with the screw-bulb adapter.

Snugly plug the B (for black, where the black wire was) socket of the connector to the red wire emerging from the conduit. Red with black, and B stands for black here. It’s for the hot wire.

Plug the blue wire into the unmarked socket of the push-in connector.

Testing, testing

I highly recommend plugging in your bulb, turning on the power at your electrical box, and testing that your retrofit works.

My first retrofit took me three and a half hours and required several additional trips to Target and Home Depot to buy stuff I forgot or didn’t know I needed.

TURN OFF YOUR ELECTRICITY AT THE BREAKER BOX

BEFORE PROCEEDING.

Tuck wires away

With the power turned off, tuck the wires neatly into your junction box.

If paranoid, use electrical tape to shepherd the vestigial wires poking out of the ballast.

Don’t forget your flashlight!

After grabbing your flashlight and whatever else doesn’t belong in the ceiling, close the junction box.

Slide the can up

Disconnect the LED and slide the can back into place using your marker lines as guides for where the screw holes are. Screw the can firmly back into place.