Pool light question....

[DLO]

I have a 500w niche lamp in the deep end of the pool. I replaced the lamp when I opened the pool this spring. I haven't had the light on very much until just recently as we are spending more time in the pool after dark. The light will stay lit for 30-40min, spontaneously turn off for 10 min or so and turn back on...and repeat that cycle. The GFI never trips. Any ideas?

 

[Poolsean]

The light fixture has an internal high temperature overload feature that will do as you're describing. There should be water flowing into the light niche housing and surrounds the light fixture to help keep it cool. If this is sealed off somehow, it's not allowing the water to get in there to cool it off.
The light fixture itself (the physical component that the bulb is in) should be completely sealed off to water.

 

[DLO]

Poolsean,

There is plenty of water circulation in and out of the niche and the fixture is sealed and dry.

 

[Poolsean]

The only other component is the 12 V transformer...unless you have a much older pool and it's 120 volts.
A 500 Watt system is not too common anymore.

 

[DLO]

There's no transformer...it's an older 120v system. The pool itself is 18 years old. The fixture is a Hayward.

 

[New2Me]

Are you sure that a 500 watt bulb is what it took? Mine took a 300W Halogen tube bulb, the kind like go in the 500 Watt Halogen work lights that Wally-world sells. Finding a 300 watt wasn't too hard, our local Rural King carries it.

 

[patf11]

My last pool has similar light problem. It was a 300 watt, 120 volt bayonet mount bulb. It would quit after 15-20 minutes and then start working about 5-10 minutes later.

Problem turned out to be corrosion in the base. Contacts and spring were corroded. After cleanup it worked perfectly.

Not sure if you have same problem, but it might be worth checking.

 

[DLO]

New2Me, yeah the fixture is rated for a 500w lamp. I replaced the bulb this spring with the same bulb that was in it when we bought he place. The 500 seems like it would be a little overkill, but the pool is pretty large (see sig) and with only one light, the pool is non too bright using the 500w'r.

patf11, I have to pull the fixture out of the niche today anyway. I'll check the contacts and spring. I called Hayward a few min ago and they said it sounds like that if a bulb replacement doesn't fix the problem, the themal cut-off switch in the fixture went bad and I'll need to replace it.

 

[Zoltan]

New guy, first post. I recently replaced the quartz halogen bulb in my underwater pool light with a tungsten bulb. The light works but it looks like the fixture is full of water...is that possible? I'm not a big fan of electricity, thanks to a couple of close calls, and am of the opinion that it's akin to witchcraft. I'm going to take the fixture apart tomorrow and install a new gasket...but I'm curious. Zoltan