Outdoor spa tripping GFCI

[James L]

I did a panel change out last summer, and one of the breakers was for an outdoor spa

There's an old spa panel outside and it has about (4) breakers in it, none GFCI

I told him the least expensive option would be a 50 amp GFCI 2-pole in the panel inside, so that's the route he went

He just called me couple of days ago and said that 50 amp breaker keeps tripping everyday, whereas it had never tripped before.

That's easy enough, except for one wrinkle...

He said it only trips at night. He said he has waited there as late as 10:30 p.m. with everything running and it never trips. So he'll go home and come back in the morning to find that it's tripped.

I know it's very limited info, but does anything stand out?

 

[LarryFine]

Experiment by turning one breaker on (or off) at a time, each night.

 

[James L]

Experiment by turning one breaker on (or off) at a time, each night.

I suggested that, except the heater can't be on without the pump

 

[Little Bill]

I've never had good luck with a GFCI breaker feeding anything outside if the load is very far away. You get cumulative leakage that adds up to above the threshold of the GFCI and trips it. I would opt to put the GFCI outside at the load. You can buy a spa disconnect with a 50A GFCI breaker in it cheaper than buying just a GFCI.

 

[jim dungar]

I suggested that, except the heater can't be on without the pump

But the pump can be on without the heater. Night one pump on, heater off, if GFCI holds the problem is not the pump circuit.
The odds are it is a problem with the heater. Is there a high heat mode that turns on when it gets cold later at night?

 

[retirede]

Since it’s been running OK since last summer, I’d guess the heater is developing leakage. It probably runs more at night.

 

[James L]

But the pump can be on without the heater. Night one pump on, heater off, if GFCI holds the problem is not the pump circuit.
The odds are it is a problem with the heater. Is there a high heat mode that turns on when it gets cold later at night?

The high heat mode is a good question.

 

[ptonsparky]

That's what a Megger is for.
Most likely good meter of any kind.

 

[ActionDave]

I'll take Heater in The Spa Needs Changed for $200 Alex. What is causing my GFI to trip?

 

[ptonsparky]

I'll take Heater in The Spa Needs Changed for $200 Alex. What is causing my GFI to trip?

FWIW, I did work on one that condensation was dripping down onto the control board and causing the trip.