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Before trying to info below, if BOTH the pool AND spa went out at the same time, there is a possibility that there is a GFC-I somewhere near the pool equipment that went out. You could try resetting it or the breaker of the light is separate. the GFC-I will look like your nornal outlet in most bathrooms with the black and red Test / Reset buttons
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Changing a light is not too complicate. First you need to know what kind of lights you have. Most large pool lights are your standard 500W bulb. These can vary fro 12V to 120V depending on the model. Most lights I have handled are as follows. Some pictures would sure help, but here are the basics for a standard POOL light. First, you will need to know what model you have. Almost all installers leae enough wire to get the light to the deck. So make sure the light is off. Then there will be a screw in the top of the ring. Once out, you will either remove the ring the holds the lens cover and the body together OR you will unscrew nuts around the back of the ring light housing itself. Once out you will want to replace the O-Ring and the Bulb. NEVER re-use the same gasket. Once you replace the bulb, put he oring on the lens and reassemble the housing. If it has a band around the light, lightly tap the ring as you tighten the screw to take any slack out. If it is the screws style, slowly do them as you would a car tire.. Work in opposites and double check as you finish up. After this is done, you can wrap the cord around the fixture and place it back in the hole. There is usually a tab on the bottom of the bracket in the wall, so putting bottom in first than bringing the top to the wall is probably easiest. A spa light is similar, but these MAY have halogen lights in them. If this is the case, never touch the new bulb with bare fingers, the oils from your hand can make the light blow. do the same, as a pool light and place back in hole. One thing to keep in mind, when you put it back in, rotate the fixture under the water a few times, this will allow any normal air trapped in a crevice to come out, then make sure no more bubble come up. If you have a leak coming up, you may need to check the piece that secures the lens to the housing. If you can post a pic of your fixture I may be able to give a little more info. If you can get them out the pool they won't have any issues as long as they are off and they can stay out too, since the gaskets will be replaced. If there is water in the fixture, don't bother
