How to Replace an Old Pool Light Without Draining the Pool

Let me guess. Your pool light has been dead for weeks. Maybe it flickered a few times and gave up, or maybe the water inside the lens looks like iced tea. You figure it's time for a new one, but the thought of draining thousands of gallons of water just to change a light bulb has been sitting in the back of your mind.

Stop right there.

You do not need to drain your pool. I repeat: do not drain your pool. Draining a pool is risky business. Fiberglass pools can actually pop right out of the ground like a bath toy. Vinyl liners can shrink and never fit the same again. Concrete pools can crack. It is messy, expensive, and completely unnecessary.

Pool lights installation are designed to be replaced from the deck. The water stays put. You stay dry. The whole job takes about an hour if you know what you are doing. This guide will show you exactly how to pull it off.

Before You Touch Anything

Here is how pool lights work. Your light sits inside a little cave built into the pool wall called a niche. The light fixture is attached to a long cord that runs through a hollow pipe (conduit) all the way to a junction box near your pool equipment. That cord is the key. It slides in and out of that pipe.

Most standard pool lights are held in by exactly one screw at the top of the faceplate. Remove that screw, and the whole thing swings out like a little door. You lift it onto the deck, and the cord feeds out behind it. No draining required.

But first, electricity. This is non-negotiable. Go to your main electrical panel. Find the breaker that controls the pool lights. Flip it off. Not the light switch. The breaker. If someone walks by and flips that switch while you are elbow-deep in water, you are in serious danger. Tape the breaker off if you have to. Be absolutely sure.

What You Will Need

·       New pool light or LED retrofit kit

·       Flathead screwdriver (maybe Phillips, depends on your screws)

·       Wire cutters and strippers

·       Waterproof wire nuts

·       Electrical tape

·       Towels

·       A helper is nice but not required

·       Patience

Step 1: Get That Old Light Out

Stand at the edge of the pool. Look at the light. There is one screw up on the top of the faceplate. That is your target.

Remove that screw. Keep it somewhere safe. You will need it later.

With your hand now grip the upper edge of the light and draw it to yourself. The lower part will serve as a hinge. The light will swing away and begin floating or hanging in the water. Take it and place it at the deck of the pool.

Water will drip everywhere. This is normal. Have a towel handy.

When lifting, the cord will slide out of the conduit. Keep pulling until you have a few feet of cord on the deck and the light-giving apparatus next you. You may think you are fishing, and you are fishing, at that.

Step 2: Trace the Cord to Junction Box.

Proceed with the cord with the light after it disappears into the wall or the ground. Trace it to the equipment pad. Close to your pump and filter there is a gray box made of metal or plastic. That is the junction box.

It is likely to have a length of spare cord lying there. That is good. It is that you have time to play with.

Always take a scrap of tape and label the cord immediately when you unscrew it before you disconnect it to the conduit. This will assist you in the amount of cord you will have to feed back later.

Step 3: Unconnected the Old Fixture.

Open the junction box. Wire nuts will be used in connecting black to black, white to white and green or bare copper to ground.

Make sure that your breaker remains off. Have a voltage tester, in case you can. Who knows, unless you make it start, then you can just make an assumption that it is alive and handle it with care. Better paranoid than dead.

Take off the old light wires and unscrew the wire nuts and part the old light wires out of the house wires. Loose the clamp that holds the cord in position at entry point into the box. Pull the old cord out. The former light is now absolutely out of touch.

Step 4: Pull through the Old Cord with the New Cord.

It is the one that seems to be magic at the time when you do it. You will get the new cord on the old cord and make the old cord your pull string.

Peel off approximately two inches of insulation on the end of the old cord and on the end of the new one. Bend the copper wires in a cross. Enclose the connection with electrical tape till it does not make it bulky. You would have it thick enough to draw you but thin enough to go through the pipe.

Now go back to the pool deck. Have your helper pull the old cord from the junction box side while you feed the new cord into the conduit at the pool side. Pull slowly and steadily. If it gets stuck, do not yank. Pull it back, check your tape joint, and try again. A little silicone spray can help if the pipe is tight.

Keep pulling until the new light fixture is sitting on the pool deck and the new cord is visible at the junction box.

Step 5: Wire It Up

Strip the ends of the new cord wires. Connect black to black, white to white, green to green or bare copper. Use waterproof wire nuts. Regular wire nuts will corrode over time near a pool.

Tug each connection gently to make sure they are secure. Reinstall the strain relief clamp so the cord cannot move around. Fold the wires carefully into the box and put the cover back on.

Do not turn the breaker on yet. The light is still sitting on the deck. It needs to go back in the water first. Running it dry will damage the new fixture.

Step 6: Deal with the Extra Cord

You probably have extra cord coiled up near the junction box. That is fine. You do not want twenty feet of slack floating around back there. Coil it neatly, about 12 inches in diameter, and secure it with a zip tie or tape. Hang it on a hook or just set it neatly beside the box.

Do not kink the cord. Do not pinch it. Just make a nice, loose coil.

Step 7: Put the New Light in the Water

Go back to the pool. Gently lower the new fixture into the water. Guide the bottom edge of the faceplate into the little groove or tab at the bottom of the niche. Push the top of the light toward the wall until it sits flush.

Reinstall that single screw you saved from earlier. Snug is fine. Do not crank it down like you are building a deck. You can crack the plastic.

Step 8: Turn It On

Go back to the breaker. Flip it on. Go flip the light switch.

If you did everything right, you should have a beautiful, bright pool. If it does not turn on, turn the breaker back off and double-check your wire nuts. Did you match the colors? Are the connections tight? Did you forget to reconnect the ground?

It happens. Just check your work.

Why You Should Upgrade to LED Right Now

Since you already have the old light out, this is the perfect time to upgrade. LED pool lights are better in almost every way.

They use way less electricity. Your old incandescent bulb was basically a space heater in the water. LEDs run cool and cheap.

They last forever. Incandescent bulbs burn out every year or two. LEDs can run for ten years or more.

They look cooler. Many LEDs change colors. You can have blue, green, red, purple, or slow fades. Some connect to your phone. Some sync to music. It is your backyard. Make it fun.

LED retrofit kits are low in cost and easy to install. The upgrade will be paid in the long run by the energy saved.

When You Should Call a Professional

This entire procedure presupposes a typical pool lighting system. Supposing that any of these is so, it may be time to solicit assistance:

•         You open the junction box and discover melted or corroded wires.

•         The cord will not give way when you attempt to draw it.

Your pool has lights without a niche, or some laborious European system.

•         You simply do not like to play with electricity around water.

It is no shame to call an electrician. A service call is do little when compared to your life.

Keeping Your New Light Alive

You have just completed your Pool Lights Installation. You saved money, retained the water in the pool and had something new. Nice work.

Now take care of it. Clean the lens using a soft brush. Also be sure to check the rubber gasket at least once a year when opening the pool. When your GFCI breaker trips and remains tripped that is not to be ignored. That normally indicates that water is finding its way in somewhere.

Minimal maintenance is a lot. Get your light on the right side and you will have it years to come.

Final Thoughts

This is what Pool Lights Installation is about. This is very scary until you come to know that the engineers have already worked out how to make it easy. The cord is the tool. The water stays put. It is nothing but a replacement of one good with another.

I have done this myself at too many times to count. The first time, I was nervous. I continued to wait until something went wrong. However, it was precisely as it should have worked. It is the art of good design.

So go ahead. Order that new light. Pick a nice color. Snail mail it, take the old one out and slap the new one in. A week from now you might be swimming in stars in your backyard pool.

And the best part? You did it yourself. You did not drain the pool. you did not give some guy five hundred dollars. You have only traced the cord, and turned some screws.

This is what good Pool Lights Installation is about. Easy, harmless and quite achievable.

Switch that one more time, and play with the glow. You earned it