The most important aspect of bulb replacement is to make sure it remains water proof. Avoid any damage to the bulb that could result in electrical shock to swimmers.

1. Turn off the power and remove fixture from the niche by removing the top lock screw.

2. Remove the lens held in place by screws or a clamp. Gently pry the lens from the fixture taking care not to damage the lens gasket.

3. Remove the old bulb and replace with a new bulb. Note – inside some fixtures is a bare coiled spring wire that is designed to break a circuit. Without the bulb, this lies to one side of the fixture. Hold this up against the opposite side and screw in the new bulb. If the bulb bursts when in use, the spring wire will sweep across the filament, cutting the electricity in the circuit.

4. Place the fixture on the deck and turn on the light to make sure it works. Without the lens on, the heat can escape. Note: Never operate a closed light fixture out of the water.

5. Reassemble the fixture. It’s a good idea to use a new gasket, because the old one is likely degraded by use, heat and chemicals. If it doesn’t fail immediately, it probably will before the bulb needs to be replaced again.

6. Lay the fixture in the water and look for leaks. Hold it under water and check for a steady stream of bubbles which indicates it is filling with water. If so, take it apart and dry it thoroughly before returning to step 4.

7. If the fixture passes the leak test, reset the fixture back in the niche.

Credit: Swimming Pools, Spas, Hot Tubs, Fountains, and Similar Installations: Mike Holt, page 13: Article 680, based on the 2017 NEC.