Electrical Conduit & Moisture/Water

license007

Member
Feb 4, 2021
5
Fort Worth, TX
I'm in the midst of replacing my pump and adding a SWG. The plan was to keep the 220 into the timeclock but move the pump wiring to the VS pump to LINE and the SWG to the LOAD. The electrical setup involves two 1/2 conduits feeding into a switch which feed into the time clock. . The first conduit comes from around the house and has 5 solid wires for the 220 and also a 120 for the light that isn't currently used. The second conduit sends the 120 wires around the corner to a GFCI outlet which feeds the light. Both exposed portions of the conduits were in bad shape and the one that fed to the light had a crack and decent size hole in it.

I dug down past the angle and carefully trimmed both conduits so i could put new elbow and new cpvc up to the switch/time clock. When i trimmed the PVC pipe it had quite a bit of water and some mud that came flowing out. At first this seemed like a big concern, but I talked to an electrician who said it is very common to find water and moisture in the clay soil around here in conduit and if the layout involves going downhill (which it is) it is inevitable after a few years since the seal isn't perfect. (This setup is 20 years) He said as long as the wire is insulated and wet rated not to worry, but make sure the breaker is a GFCI (which it isn't yet..). Meanwhile another electrician told me the whole thing was compromised and I should have the entire operation replaced from the breaker which they can do for an amazing price! I did some additional searching on electrical forums and water in the conduit does seem to be a very common problem, but wondering if anyone else has encountered this or has thoughts on the matter?

I have confirmed all the wires that feed from the breaker are 12gauge THHN Oil resistant and the wires seem to be in great shape no blister or wear concerns. Attached the best picture i have since I've since removed everything but the time clock since i was replacing with new boxes etc.
 

Attachments

  • electrical_LI.jpg
    electrical_LI.jpg
    347.4 KB · Views: 9

Mdragger88

Bronze Supporter
Jun 1, 2018
1,921
Hernando, Ms
Pool Size
26000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Intex Krystal Clear
There is water in most electrical conduits that are buried. We use a vacuum to blow them out before pulling wires on regular occasion. The level will likely never reach the box if it is above ground level. Turn it off before working on it & u should be fine. If u wish to re pull the wire for peace of mind prepare to get messy.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,667
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
He said as long as the wire is insulated and wet rated not to worry,
...
I have confirmed all the wires that feed from the breaker are 12gauge THHN Oil resistant

The issue I see is THHN wire is NOT wet rated You need to use THWN wire. Stand-alone THWN cables are coated in PVC, as opposed to vinyl, to assist in water resistance.

If you are correct with the THHN wire existing in a wet conduit then you should rewire.
 

license007

Member
Feb 4, 2021
5
Fort Worth, TX
Thank you both for the reply. I took a closer look at the wires this morning (hard to read at dusk!) and there is a bit more detail. It says THWN/THHN-2 Oil & Gas Resistant 12 AWG or AWM VW-1.

Looking on a quick web search it seems they are both THWN and THHN rated so would be ok for wet locations and conduit since they do have the PVC jacket.
 
  • Like
Reactions: Mdragger88