How to Change a Pool Light Bulb: Follow These 11 Steps



Uh-oh! Your pool light burnt out and you don’t know what to do. Guess you’ll just have to grab a new one out of the closet and swim on down to replace it… 

If only it were that easy, right?

How to Change A Pool Light: DIY vs Hiring a Pro

Changing a pool light bulb is a bit trickier than changing one in your house and comes with a few more hazards. If DIY is not in your vocabulary and anything involving the word “electrical” makes you cringe, it may be a good idea to hire a professional on this one. 

However, if you are undaunted or want to try your hand at some hands-on pool maintenance, you’ve come to the right place. 

Finding a Replacement Bulb

Before we talk about changing your pool light, you need to have all your ducks in a row. That means finding your replacement bulb before you yank out the old one.

Your first step is to determine the correct replacement pool light bulb and lens gasket for your pool light fixture. Unfortunately, each pool is different and so are the lights, so this is not a one-size-fits-all situation.

What to Look for in a Replacement Bulb

You’re going to want to get a light bulb that is more-or-less identical to your old one. Here, wattage and voltage are especially important. To work out which light bulb model you need, you can pull out your pool user manual to find out the exact type of bulb the fixture requires. Make sure that the new one you buy matches the size, brand, and serial number.

Pro tip: If you don’t know what type of replacement bulb you need to purchase, all hope is not lost! Just proceed to the next step below, “Removing Your Old Bulb” and you can find out what you need from the label and serial number on the old one.

Most often, when you’re looking to replace your pool light bulb, your old one has burnt out and you’re just looking for an exact replacement for the bulb. But maybe you’re actually looking to upgrade your bulb or even add some party flair?

If you want to upgrade, you do have some freedom when replacing your bulb. You got choices! Perhaps you’re looking to save on energy costs with a super-efficient LED bulb? Or maybe you want some fun color-changing lights for your next nighttime pool party? Either way, we got you covered. Just make sure to match size and specs and you’re good-to-go.

Product Recommendations

Need some help choosing? We’ve got a few recommendations for you below. We alos have a dedicated post on the best pool lights.

Pentair 78428100 Amerlite...
Pentair 78428100 Amerlite...
  • World standard of reliability
  • Stainless steel face ring with uni-tension clamp
  • Superior light diffusion
Eurus Home 120V 35W Pool Light...
Eurus Home 120V 35W Pool Light...

Removing the Old Bulb

Before you get started, it’s a good idea to read through all manufacturer instructions, checking to make sure you have the necessary equipment. Once you begin, keep going! No half-finished projects here. 

It’s important to follow the instructions closely. We’re going to walk you through how to change a pool light step-by-step, and hold your hand the whole way. But if you’re skimming through the list and think it might be over your head… it might be a good idea to hire a pro for this one.

What You’ll Need to DIY

  • Replacement pool light bulb
  • Replacement lens gasket
  • Philips and/or flathead screwdrivers
  • Multimeter (voltage tester)
  • Some dry towels 

What Are The Steps Involved?

As we mentioned above, if you don’t know the specs to buy a new bulb, you’re going to need to remove the old one first.

Once you get the old bulb out, you can find all the necessary info like manufacturer, model/serial number, wattage and voltage, all of which are usually found on a sticker on the back of the light housing itself.

Step 1: Safety First! Turn Off the Power

Water and electricity don’t mix. The first (and most important step) is to turn off all power to your pool. Most commonly you’ll have a switch in your home’s circuit breaker box labeled “pool”. Switch this to the off position and then try to turn on the pool lights to make sure there is no power.

What? No “pool” switch in your breaker box? No problem. Some pools have their very own breaker box in another location. If you don’t see the right switch in the main electrical box, have a look around your pool equipment to find the right box.

Once you’ve checked that the power is off and no electricity is running to the pool… check it six more times. Getting electrocuted is not part of the process.

Pro tip: If you prefer, you can drain some water from your pool to allow you to reach the fixture more easily. This is not necessary and will entail the extra steps of refilling and rebalancing the water at the end. We’re not bossy, this one’s entirely up to you.

Step 2: Remove the Top Screw from the Light

Usually, there is only one screw holding the light fixture to the wall of your pool. This is called the “screwlock” and it’s most likely going to be at the top of the fixture. In most cases, the screw will be a Philips screw but some are flatheads. 

You’ll need to reach your arm down into the water for this step, so laying on your belly next to the pool should work. If your light fixture is really deep in the pool or you have shorter arms, you may have to hop in. So grab your screwdriver and get to work!

Step 3: Pry the Light Fixture Out

When the screw is out, put it in a pocket or baggy to make sure you don’t lose it. Next, you’ll want to use a flathead screwdriver to pry the light fixture out of its niche box. Most pool lights will have a tab at the bottom which allows you to pull the fixture away from the wall.

Use the screwdriver to help you loosen the tab and once it’s out, use the screwdriver to loosen the fixture in several other locations to get that baby open. The majority of pool light fixtures have a surplus of wire to allow you to remove it from the pool and set it down on the deck. Grab one of the towels you brought to set it on in order to avoid accidental lens scratching.

If the cord doesn’t unravel easily, grab the cord closer to the wall and try giving it a few gentle tugs to loosen it. (Note how the excess cord is stored so you can replace it the same way when you’re reinstalling the light later on.)

Step 4: Test the Wiring

More safety precautions! We really don’t want you to get hurt here, so we’ve added an extra safety step. Hey, if your electricity was still on by accident, you’d be thanking us right about now. 

Grab your voltage tester (multimeter) before touching the wires with your hands and test to make sure there’s no electricity running through there. If you’re multimeter registers anything, that means something hasn’t been turned off. Double-check your that your pool breaker is turned off before going on to the next step.

Step 5: Take the Fixture Apart

If your multimeter registers a flatline, you’re good to go! It’s time to take the light fixture apart. Spread out a dry towel on the pool deck to give you a good work surface (and to ensure you don’t scratch the lens).

Start by removing any screws or clamps and keeping them in a safe place for later. In order to reach the light bulb, gently remove the face ring and pull apart the lens and the lens gasket. 

You may notice some corrosion here if your parts are pretty old. Take care when disassembling these pieces and make sure not to drop anything in the pool. Grab a damp rag to remove any old gasket residue from the surface of the lens.

Step 6: Remove the Old Light Bulb

Steady now. These light bulbs are finicky things so you should take great care in this next step. Use one of your dry towels to grasp the bulb before slowly and carefully unscrewing it counterclockwise. When it’s out, take the towel to dry the inside of the fixture.

Installing the Replacement Bulb

Congratulations! You’ve come so far. Now, we only have a few steps to go.

If you didn’t already know what type of bulb you needed, now is the time to take a peek at your old one and get the info you need. If you already have your replacement bulb handy, let’s get started!

What are the Steps Involved?

Step 7: Screw in the New Light Bulb

Once you’ve found your replacement light bulb from the specs of your old one, you can replace that bad boy.

Make sure you never touch the lightbulb directly. Halogen bulbs are especially fragile and can even be damaged by the oils on your fingers, causing them to burn out more quickly. Simply use a towel to gently grip the new bulb and screw it in, the same way you took out the old one.

Tighten securely but do not over-tighten the new bulb. Remember, “gentle” is the name of the game with these delicate bulbs. You don’t want to accidentally break it before you even get to use it. 

Step 8: Test the Light

Great! Now the new bulb is in and you’re almost ready to put the whole thing back together. But first… let’s make sure that new bulb actually works before you go to all that trouble.

Grab a friend, spouse, kid, or neighbor to watch the light while you very quickly turn the power back on. We’re talking 2-3 seconds, max. We already mentioned that these lights are fussy but seriously, they are really unhappy when turned on outside of the water.

Just a quick peek to make sure the new bulb works and then turn the electricity right back off. If you leave the light on for more than 5 seconds, there’s a chance the bulb will burn out. Normally in the pool, these halogen bulbs have the water to cool them off. So without the water, they get extremely hot.

Don’t forget: Once you’ve tested the new bulb, make sure to turn the power off again completely to finish installing the fixture.

Step 9: Replace the Lens and Reassemble the Fixture

Now that you’re sure that the new light bulb works, let’s put everything back together. Grab your brand-new lens gasket to install around the lens. Then, put your lens back in place covering the bulb.

Basically, go ahead and put the whole fixture back together the way you found it. Make sure to keep a towel on-hand to dry out any water that may have gotten into the fixture. It needs to be super dry before you seal it back up. 

Step 10: Check for Leaks

Once the fixture is sealed with new lens gasket firmly in place, you’re almost ready to pop that sucker back in the wall. But first… let’s make sure there are no leaks in the housing.

Take the fixture and submerge it under the water, checking for air bubbles. We don’t want to see any air escaping from the sealed light fixture at all. If you happen to see any bubbles… bummer. Haul the fixture out of the water and take the whole thing apart, drying as thoroughly as possible, before putting it back together.

Repeat this procedure and test until you don’t see any air bubbles at all.

Step 10: Replace the Light Fixture in the Pool Wall

No bubbles, no leaks, a functioning light — we’re almost home free! Now you safely replace the light fixture in the pool wall. 

Before you do anything, you’re going to need to feed the excess wiring back into the wall where you found it. An easy trick here is to wrap a bit of the cord a few times around the base of the fixture before you insert it back into the wall.

Next, you can put the whole fixture back into the hole in the wall, while making sure that the screw holes line up correctly. Replace the screw(s) and use your screwdriver to tighten everything into position.

Step 11: Turn the Power Back On

Last, but not least! Go ahead and switch on your pool’s circuit breaker to make sure the light comes on. When you see it light up, it’s time to celebrate with a beautiful evening swim.

Taking a Nighttime Dip Just Got Better

Great job — you just learned how to change a light bulb!

Now you can really enjoy your pool night and day. Swim whenever you want with some fun or relaxing mood lighting. You can also have the whole neighborhood over to show them your new lights with the added bonus of bragging about your DIY skills.

Categories: Pool Care, Pool Problems