Amerlite® - The world standard of reliability for pool lighting
Amerlite®, the world standard of reliability for underwater lights, features a stainless steel shell, 8-3/8 in. prismatic tempered glass lens, and stainless steel face ring with uni-tension clamp. Amerlites are UL listed to install in full-sized Pentair Pool Products, American, PacFab and Purex niches.
Note: All 120 volt pool and spa lights must be connected to a branch circuit protected by a ground fault circuit interrupter (GFCI).
Note: All cord lengths over 50 feet on 12 volt lights create resistance that dramatically reduces the light output. This condition exists on all low voltage lights regardless of design or manufacturer.
Notice: Underwriters Laboratories has listed Pentair Pool Products lights for use with Pentair Pool Products, American Products, Purex, or PacFab niches only. To ensure proper grounding/bonding connections install only Pentair Pool Products lights in Pentair Pool Products, American Products, Purex, or PacFab niches. P_L
Note: Chrome-plated brass face rings do not fit in the QuickNiche.
Removing Dirt and Debris
If the pool light is not affected by the change from the pool to the bowl of water, you should carefully examine all of the parts to check for signs of debris. There is a small amount of water algae which builds up inside the light niche, and this can prevent the light from turning on and off, and can also cause the bulb to blow underwater. Remove any dirt and debris from the light, and clean thoroughly.
Check the Electrics
Just as with a normal light, when it stops working you need to check out the electrics. Start with the circuit breaker for your lights. If this has popped out, then dry pressing it back down, and then look at the lights in the pool. You may find that one of the bulbs has burst, and triggered the circuit breaker. You should also check that there is no water in the light, as this can cause the breaker to fail, and then not properly reset. You should pull out the light and check.
You can also replace the bulbs in your lights in order to check whether this is the problem. It is not a good idea to try this bulb in your pool, so consider that you may have to install it in the bowl of water, and then transfer it to the pool once you know that it is working. Take your light into the pool, and screw into place carefully. You should lower the water level while you are installing the light, and then raise it when you are no longer near the pool.
Direct customer to this link for further detailed info: http://swimming.about.com/od/poolandspamaintenance/a/fix_pool_lights.htm