I've had troubles with my hot tubs GFCI tripping this spring. When refilling, after heavy rain and powerwashing desk. It takes days sometimes weeks to dry out.

I have disconnected everything from service pack.. still trips. Tried new GFCI.. trips.

Now I have disconnected main power wire from service pack.. trips. Disconnect main power wire out of GFCI to tub and finally it doesn't trip!

How on Earth can a 6 guage wire become faulty? It runs through conduit under garden and then open under deck.



Disconnect main

 

The wire insulation could have been skinned open if it was pulled in the conduit too roughly or bent too sharply in a junction box. Also verify the wire type is THWN-2. If someone used a wire type that is not wet rated the insulation might be breaking down.

At least it should be a relatively easy fix to pull the old wires out and pull new ones in. Use the old wires to pull through a small rope you can use to pull in new wires.

P.S. what do you mean by "open under the deck"? Hot tub feeders must be in conduit the whole way, so I hope you mean the conduit is open under the deck, not the individual wires.

 

Thank you for your reply! By open I mean that the insulated wire is not in conduit under the deck.

 

If you disconnected the wiring to the tub from the gfi and the gfi no longer trips that is pointing to an issue with the tub itself.

 

With everything disconnected from the feed out to the tub and only the feed cable connected and it trips, sounds like the cable , what kind of cable is it?
Geo

 

Yes, tripping with only feed cable connected to gfi. Its marked 6/3 NMWU sun/Sol resistant 300V.

 

6/3 NMWU (non metallic wet underground) is a three wire UF cable used in Canada.

A typical hot tube/spa is 120/240v and requires four wires. Two hots, a neutral and a ground.
That cable supplies 240v only and a ground.

 

That's correct, us Canadians must not count ground wire. It's a 240v tub and the 6-3 has 2 hots,neutral and ground.

I just dug up the section under dirt, looks clean but ground is moist.

 

The wire supplier I looked at showed 6/3 NMWU as expressly three wires. I believe if you have four wires you have 6/3 UF w/gr. Could be the same thing.

 

Problem solved. Thanks for all your input everybody. The cable traveled from the GFI box through a conduit down into the dirt and there is no elbow where the cable went out of the conduit and into the dirt.it had a sharp bend on the edge of the conduit and insulation was compromised.The new cable is in and everything is working as it should.

 

Glad you’re all set, thanks for the update .
Geo