ChuckDavis
04-26-2013, 11:12 PM
I have an in-ground concrete pool (epoxy paint finish) with an Amerlite underwater light. The chrome bezel continuously turns black. The tarnish can be scrubbed off, but always returns. (There is also an ongoing, low-intensity battle with minor metal stains, with no known source for the metal.) Other than the niche and pool light, there is no metal in contact with the water. (No stairs, rails, etc.)
The tarnish probably indicates a bonding problem, but.................
There is a bond wire from the light niche to the bonding lug on the pump. The bond wire is #8 *stranded*, however. The wire connects to the inside of the niche and runs up the conduit with the power cord. The attachment of the bond wire to the niche is slathered in some sort of caulk. Using a wire nut in the J-box, the stranded bond wire is connected to another run of #8 stranded wire that goes back to the pump. It is a 30-40 foot run from the niche to the pump.
While the pool was partially drained I used a VOM to test, and there is continuity from the niche to the bonding lug on the pump. I connected my test wire to the screw hole where the screw holding the bezel in place is inserted, so I can assume that there is continuity from the bezel to the pump.
There are two other bond wires (also #8 stranded) connected to the bonding lug on the pump. One comes from the heat pump. The other comes from the concrete pool deck, with a bond wire from the rebar in a hot tub slab that I poured spliced into it. I have no idea of the quality or condition of the bond in the concrete pool deck.
The only real weirdness that I can see is the bond wire connection inside the niche, possibly in contact with the water if the caulking has failed. Since the goal of bonding is to keep everything, including/especially the water, at the same potential, I'm not sure this is a problem.
I had the entire pool system rewired by an electrical contractor. Beauzeax, my name for the previous homeowner who installed the pool.............and who owned a pool construction company (!), had totally screwed it up. An AFCI on the light, no GCFI's anywhere else, and the bond wires disconnected since they caused the AFCI to trip. (I wonder if there's a clue there.) The new GCFI on the pool light has not tripped.
The pool and pool light are around 15 years old. Is there any chance the power cord to the light is failing and leaking some current?
Does anybody have any ideas or suggestions on how to diagnose or fix what probably is some sort of current flow causing the tarnish on the light bezel? Can anybody think of any test points to determine if/where there is a voltage differential? Is there any way to test for leakage from the pool light power cord with the pool now being refilled?
Thanks.
(Here's another laugh. Beauzeax ran 75 feet of undersized gas line from the meter to the (now removed) pool heater............USING PVC! The undersized pipe caused the burners in the heater to run cool and moist, which rusted out the burners and baffles.)
The tarnish probably indicates a bonding problem, but.................
There is a bond wire from the light niche to the bonding lug on the pump. The bond wire is #8 *stranded*, however. The wire connects to the inside of the niche and runs up the conduit with the power cord. The attachment of the bond wire to the niche is slathered in some sort of caulk. Using a wire nut in the J-box, the stranded bond wire is connected to another run of #8 stranded wire that goes back to the pump. It is a 30-40 foot run from the niche to the pump.
While the pool was partially drained I used a VOM to test, and there is continuity from the niche to the bonding lug on the pump. I connected my test wire to the screw hole where the screw holding the bezel in place is inserted, so I can assume that there is continuity from the bezel to the pump.
There are two other bond wires (also #8 stranded) connected to the bonding lug on the pump. One comes from the heat pump. The other comes from the concrete pool deck, with a bond wire from the rebar in a hot tub slab that I poured spliced into it. I have no idea of the quality or condition of the bond in the concrete pool deck.
The only real weirdness that I can see is the bond wire connection inside the niche, possibly in contact with the water if the caulking has failed. Since the goal of bonding is to keep everything, including/especially the water, at the same potential, I'm not sure this is a problem.
I had the entire pool system rewired by an electrical contractor. Beauzeax, my name for the previous homeowner who installed the pool.............and who owned a pool construction company (!), had totally screwed it up. An AFCI on the light, no GCFI's anywhere else, and the bond wires disconnected since they caused the AFCI to trip. (I wonder if there's a clue there.) The new GCFI on the pool light has not tripped.
The pool and pool light are around 15 years old. Is there any chance the power cord to the light is failing and leaking some current?
Does anybody have any ideas or suggestions on how to diagnose or fix what probably is some sort of current flow causing the tarnish on the light bezel? Can anybody think of any test points to determine if/where there is a voltage differential? Is there any way to test for leakage from the pool light power cord with the pool now being refilled?
Thanks.
(Here's another laugh. Beauzeax ran 75 feet of undersized gas line from the meter to the (now removed) pool heater............USING PVC! The undersized pipe caused the burners in the heater to run cool and moist, which rusted out the burners and baffles.)