Water in light conduit in winter

[wangpeng]

First year pool owner. Fiber glass pool with two Pentair Globrite lights. When my builder installed the light, I noticed that the worker did not blow the water out of the light conduit where the electric wire goes. I was told the light was designed to operate in water. My question now is that if there is water in the pipe and the pipe is not going to be blown for winter, what if the Water in the pipe freeze and burst the pipe?

 

[Cincicobra]

I am a first year owner as well and obsessed over this same issue. My PB said don't do anything and it will be fine, as the water is essentially open on both ends and will expand if it freezes. Nobody here apparently does anything either. I couldn't take it and added 2 gallons to the conduit from the deck box after everything else was done at closing. The open chemistry database says propylene glycol may either sink or float on water, and should not separate with water once mixed so there should be some level of benefit by adding it to the conduit. Certainly zero harm. With the water in the pool idle, aside from separating and sinking below the water in the conduit the water in the conduit should be fairly protected. I went overboard on antifreeze out of paranoia anyway, as it's really cheap insurance and I won't obsess about what's going on underground all winter, even though the pipes are empty, plugged, and are deeply buried.

 

[Texas Splash]

Welcome! For the most part, the light and conduit area can be disregarded during your closing. Between the depth of the line, small amount of water within, and the ability for it to expand in either direction (if it even occurs), you should be fine. There are some owners who remove their large light from the niche, wrap it, and set it on the decking, but I'd guess most owners just leave the light alone.

 

[wangpeng]

Is the propylene glycol corrosive to the wire rubber cover? I am trying to do some searching, couldn’t find a conclusive answer.

 

[Texas Splash]

Is the propylene glycol corrosive to the wire rubber cover?

Corrosive? I don't think so. I found this from another thread ......

Propylene Glycol based: This product is only available at your local RV shop (and not every RV shop for that matter). It sells for approximately $5.00 - $6.00 a jug. Like the ethanol antifreeze, this product is non-toxic and safe for all RV plumbing. However, propylene glycol does not have the same fire safety warnings, nor the risk of tainting your RV plumbing system. Furthermore, propylene glycol is a lubricant and will actually work to extend the life of the seals in your faucets and toilets, unlike the ethanol based products.