A lot of water down an exhaust fan/light vent from roof with a hose

[Fred B]

There is no fixture installed yet and no power to circuit, thankfully. Just the metal box with the wires hanging out (yes, breaker is off).

one question. the wiring in the attic is all single strand and inside conduit. would the conduit protect the wiring? I know that the exhaust fan will be another story but I am praying that the wiring will be ok since in conduit and junction boxes.

IF no motor or light in place at the time, and you indeed have conduit with THWN-2 then it would not have the detrimental effects and simple dry out would be should be enough. Inform the electrician that will be wiring the fan/light in that water had come into the enclosure so that they can take appropriate cautions to ensure a clean connection.

 

[Fred B]

Where I'm at we have a lot of electrical items get submerged and in most cases after things dry out everything keeps on trucking, even if flooded by salt water. Panels, breakers, and control type equipment may or may not get replaced.

Not sure of an exact code, but we've had multiple panels over time that had been flooded by either disaster or fire department actions that panel was not replaced even thought the breaker were, the panel buss after not even five years showed pitting and corrosion even though supposedly "cleaned" by one of those disaster remediation companies. Disaster flooding will introduce more than just clean water, but all sorts of contaminants including at times sewage. Seen panels that had been submerged by flood have oily residue all over including the buss. Seen some that after being simple water entry from bad SEU, the breakers even having water inside but not tripping and energized, (the lights are on so what's the problem mentality) the breakers didn't get replaced. I show up months later to find the SD QO breakers still had water inside the trip windows. (someone else had replaced the SE)

 

[roger]

Disaster flooding will introduce more than just clean water, but all sorts of contaminants including at times sewage.

Well if it's been under sewage I hope everything keeps working because I'm not touching it.

 

[Fred B]

Well if it's been under sewage I hope everything keeps working because I'm not touching it.

Most flood water around here will include run off from farm fields and you know what they spread on them ("natural" fertilizer), and if bad enough will lift houses and mobile homes off the bases and and opening sewer/septic lines that gets mixed in too. Then add in whatever chemicals that might have been stored at someone's residence or business and fuel storage. All these potentially getting into the submerged equipment and wire. This is why it is if not required by code directly (can't quote a section) it is definitely recommended by FEMA.
See pictures all the time of people wandering through flood waters (not just to escape) and consider all this potential toxins as well as objects floating it's a miracle more aren't sickened.

 

[roger]

Fred, I have lived in flood prone / hurricane areas all my life and know what is in flood waters so you're preaching to the choir.

But simply being saturated by water is not necessarily cause for a "the sky is falling" reaction.

 

[kwired]

Thank you for the replies. Regarding the vents, the tub, sink and toilet vents are all original to the house. the fan vent was put in by a professional electrician who installed the fan so I would think he did it right but, who knows. I have a lot of fiberglass insulation up there that I know has soaked up the water so I am going to fight my husband and pay a company to come out and remove it and replace it and make sure the vents are all working correctly. I am thinking an attic inspection company that does heating and cooling that they would be able to also check the venting and fix that, too? Perhaps he water from the hose caused something to disconnect.

I was especially worried he might have destroyed the new exhaust fan/light that has not even been used yet and created issues with the wiring. When I asked google AI about it, it kept repeating that it would cause corrosion, short circuits, seep into the insulation of the wires, ruin all the electronic components etc. So I did panic. Since Ptonsparky thinks that I will be ok I feel a little better about the electrical.

Most fans the water may get to the motor - but most of them would be just fine, not a bad idea to make sure it is fully dried out before using. Corrosion risk doesn't increase much from just one incident with relatively clean water particularly if dried out right away. Something that has a regular leak is what will suffer more from corrosion.