I am having a problem with my pool light that keeps causing my GFCI to trip. My setup is that I have a 110 volt/20A breaker that connects to my 20A GFCI outlet. The load side of the outlet goes to the junction box (black wire via a toggle\light switch to engage the light) that connects my Hayward Astrolight pool light. Every time I place a reasonable load on the GFCI, it instantly trips. It will engage and power my cell phone charger, Rigid orbital sander, but will immediately trip whenever I connect my leaf blower, hair dryer or turn on the pool light.
Here is what I know:
If I disconnect the wires from the pool light at the junction box (at the diving board or load side of the GCIF outlet), the GFCI will work with the hair dryer where it would not work with before. I have also changed out 3 different 20A GFCI outlets (one even from the bathroom that uses the hair dryer); so I have ruled out the GFCI.
Also, I have had water in the junction box in the past and there was some in there this time. The previous time, I ran the leaf blower to remove all of the water from the box. I keep siliconing the face plate, but water somehow keeps getting in there. (flush with concrete). The only possibilities I know of now are is if water when down the inside the cord (where the lamps wires are) and made itís way inside the light, if there is just enough moisture in the conduit that will cause high amps to trip the circuit, or itís possible that water is inside the fixture (I really cannot tell at this point and tool cold to get in pool). The wire has silicone around it (going into the lamp side conduit) to prevent it from either moving or water going down the conduit; not really sure on the fixture side of this. I did notice that after blowing out the junction box, some water came back (likely from the pool side conduit) but was minimal. The water level appears to have always been below the wire nuts making the connection.
When it went out, I had it turned on as I was pumping water out of the pool (due to rain) and it stayed on on for about 5-10 minutes. Can anyone advise me on what I can do next to determine the problem?