Main Breaker Tripping But NOT GFCI

[parkerma]

We are dealing with an issue that arose this past winter and not addressing it until now.

Last January the heater in our tub went. It was the wiring that had corroded over time. We replaced the heater and everything was working perfectly. Please note we also recently within the past year replaced the circulation pump and flow switch. We left for a few months and came back to find that the breaker was tripped at the main panel. I inspected the GFCI, disconnected the tub and the main breaker stays on when flipped back on. I hooked the tub back up and turned the main breaker on but it would not stay on at all.

I have read that if you disconnect the components from GFCI and the breaker stays on, then it is the tub. But, wouldn't you expect the GFCI to pop as well if it was the tub since that is the first breaker in the line? It seems strange that the GFCI would not pop.

I am about to purchase a new circuit board, but want to be sure it is not the GFCI before moving forward.

 

[1poolman1]

GFCI trips on current leaking to ground (no more than 5mA [0.005A]). Breaker trips on overcurrent condition, for a spa likely 40 - 60 Amps. They detect different faults.

 

[parkerma]

GFCI trips on current leaking to ground (no more than 5mA [0.005A]). Breaker trips on overcurrent condition, for a spa likely 40 - 60 Amps. They detect different faults.

When my heater was going, that was tripping the GFCI. Now when i flip the main breaker, it flips right off. So in your opinion, would this be a possible circuit board or top side controller?

 

[RDspaguy]

GFCI breakers are both standard breakers that trip from amp draw and gfci protection that trips from a ground fault, which is what would hurt a spa user. Given the additional wire between the main and gfci breakers it stands to reason that, in the case of a high amp situation, it would be the main breaker that trips, both breakers being equally rated. That said, my money is on a bad main breaker from your description.

Now when i flip the main breaker, it flips right off.

The only thing that trips a standard breaker is heat, via a bi-metal strip. High amp draw is the way it should produce heat, but worn contacts, loose terminals, high ambient temperatures, direct sunlight, and a list of other variables also play a part. And sometimes the physical mechanism just breaks. I'd get a new main breaker.

So in your opinion, would this be a possible circuit board or top side controller?

No. In my opinion it is most likely a bad main breaker. Try replacing the cheapest part in the whole system first, before you go buy the most expensive.

So, in summary, replace that breaker!

 

[phonedave]

GFCI breakers are both standard breakers that trip from amp draw and gfci protection that trips from a ground fault, which is what would hurt a spa user. Given the additional wire between the main and gfci breakers it stands to reason that, in the case of a high amp situation, it would be the main breaker that trips, both breakers being equally rated. That said, my money is on a bad main breaker from your description.

The only thing that trips a standard breaker is heat, via a bi-metal strip. High amp draw is the way it should produce heat, but worn contacts, loose terminals, high ambient temperatures, direct sunlight, and a list of other variables also play a part. And sometimes the physical mechanism just breaks. I'd get a new main breaker.


No. In my opinion it is most likely a bad main breaker. Try replacing the cheapest part in the whole system first, before you go buy the most expensive.

So, in summary, replace that breaker!

Actually a standard breaker trips in two ways

Thermally - As you said, a bi-metallic strip heats up, and when it gets hot enough, it pops the breaker

and also

Magnetically - This uses a magnetic field generated by the current flowing through the breaker to trip open the breaker

Thermally happens when you put too many amps through the breaker for a long enough period of time to heat it up - inrush current from a motor starting will not trip it (if it is sized correctly). It is like a slo blo fuse

Magnetically - this happens when you have a large current draw, like a dead short. It happens near instantly. It does not have to heat up first.

 

[parkerma]

Actually a standard breaker trips in two ways

Thermally - As you said, a bi-metallic strip heats up, and when it gets hot enough, it pops the breaker

and also

Magnetically - This uses a magnetic field generated by the current flowing through the breaker to trip open the breaker

Thermally happens when you put too many amps through the breaker for a long enough period of time to heat it up - inrush current from a motor starting will not trip it (if it is sized correctly). It is like a slo blo fuse

Magnetically - this happens when you have a large current draw, like a dead short. It happens near instantly. It does not have to heat up first.

So would you concur changing out the panel breaker first? It just seems strange that the GFCI would not trip if it was downstream.

 

[1poolman1]

So would you concur changing out the panel breaker first? It just seems strange that the GFCI would not trip if it was downstream.

GFCI breaker or GFCI device? They are different and trip under different conditions. First thing to check is always the heater, disconnect it. Problem stop? Replace the heater element or entire heater as needed.

A spa heater will trip the GFCI device when it initially fails, usually by the heater-coil tubing (the incalloy/titanium, etc. tubing the heating coil is in) becoming compromised (cracks, etc.) allowing a small amount of water in and small current leakage to ground. This is inside the, usually, larger stainless heater housing.

Eventually, this can lead to a greater "short" that can trip a breaker. You don't mention if the breaker that is tripping is a GFCI breaker or standard.

If disconnecting the heater doesn't solve the issue, the next thing to check is the pump (or pumps). Those are the two large-current parts of a spa. Leave the heater disconnected and disconnect the pump. Problem stop? New motor or pump time. Its a process of elimination. Also note that GFCI devices can fail and no longer trip, that's why they should be tested on a regular basis.
Device:

GFCI Breaker:

 

[phonedave]

So would you concur changing out the panel breaker first? It just seems strange that the GFCI would not trip if it was downstream.

A GFCI breaker is a regular breaker with added GFCI functionality.

If I am understanding this correctly, you have a normal breaker in your panel, that runs to a GFCI breaker in a sub panel and then to your hot tub. This is a dedicated circuit with nothing else on it.

You came home to a tripped breaker in your main panel.

You disconnected the hot tub (how, what do you mean by "disconnected") and the main breaker stayed on, as well as the GFCI breaker.

You reconnected the hot tub, and the main breaker immediately trips. Regardless of what is running or not, any load trips the main.

It does sound to me like there is a issue with the main breaker. They can go bad. If you are comfortable changing a breaker out, then you may want to try doing so. You are looking at about $50 for a new 50 amp two pole breaker

 

[parkerma]

GFCI breaker or GFCI device? They are different and trip under different conditions. First thing to check is always the heater, disconnect it. Problem stop? Replace the heater element or entire heater as needed.

A spa heater will trip the GFCI device when it initially fails, usually by the heater-coil tubing (the incalloy/titanium, etc. tubing the heating coil is in) becoming compromised (cracks, etc.) allowing a small amount of water in and small current leakage to ground. This is inside the, usually, larger stainless heater housing.

Eventually, this can lead to a greater "short" that can trip a breaker. You don't mention if the breaker that is tripping is a GFCI breaker or standard.

If disconnecting the heater doesn't solve the issue, the next thing to check is the pump (or pumps). Those are the two large-current parts of a spa. Leave the heater disconnected and disconnect the pump. Problem stop? New motor or pump time. Its a process of elimination. Also note that GFCI devices can fail and no longer trip, that's why they should be tested on a regular basis.
Device:
View attachment 460779
GFCI Breaker:
View attachment 460780

We have a spa GFCI breaker outside which is connected to the hot tub. When the heater was going bad, it was tripping the GFCI. Replaced the heater and it worked fine. I doubt the heater went bad in 2 months. Now the main breaker in the house trips, NOT the GFCI breaker outside. If it was the tub, wouldn't you think it would trip the GFCI first?

 

[parkerma]

We have a spa GFCI breaker outside which is connected to the hot tub. When the heater was going bad, it was tripping the GFCI. Replaced the heater and it worked fine. I doubt the heater went bad in 2 months. Now the main breaker in the house trips, NOT the GFCI breaker outside. If it was the tub, wouldn't you think it would trip the GFCI first?

the breaker that is tripping is in the main house panel, a 50amp breaker.

 

[phonedave]

We have a spa GFCI breaker outside which is connected to the hot tub. When the heater was going bad, it was tripping the GFCI. Replaced the heater and it worked fine. I doubt the heater went bad in 2 months. Now the main breaker in the house trips, NOT the GFCI breaker outside. If it was the tub, wouldn't you think it would trip the GFCI first?

Breakers trip when either their thermal or magnetic limits are reached. Or more to the point when the mechanism holding back the spring is overcome by the spring.

When it boils down to it, breakers are a mechanical device, and they can wear out like any mechanical thing does. Breakers are designed to trip EASIER as they wear - it is a safety thing, you want a 50 amp breaker to start tripping at 40 amps as it wears out, not 60 amps.

I suspect your main breaker is worn, and your GFCI is not. That is why the main is tripping and the GFCI is not. It does not matter what is first or last "in line". Electricity does not necessarily work that way anyway.

 

[1poolman1]

the breaker that is tripping is in the main house panel, a 50amp breaker.

It is still a process of elimination. You've isolated the issue to the spa, now you need to find out what in the spa is causing the problem. Disconnect the heater. Main-panel breaker doesn't trip? Its the heater or heater circuit. Breaker trips? Leave the heater disconnected and try disconnecting the pump or pumps. Breaker still trip? Likely a wiring problem. Breaker doesn't trip, new motor or pump time.

It may be easier to start by replacing the main-panel breaker first, just to be sure. They're not that expensive, unless it is a Zinsco.

 

[parkerma]

It is still a process of elimination. You've isolated the issue to the spa, now you need to find out what in the spa is causing the problem. Disconnect the heater. Main-panel breaker doesn't trip? Its the heater or heater circuit. Breaker trips? Leave the heater disconnected and try disconnecting the pump or pumps. Breaker still trip? Likely a wiring problem. Breaker doesn't trip, new motor or pump time.

It may be easier to start by replacing the main-panel breaker first, just to be sure. They're not that expensive, unless it is a Zinsco.

Right, that is what i am going to do first.

 

[RDspaguy]

It is still a process of elimination. You've isolated the issue to the spa, now you need to find out what in the spa is causing the problem. Disconnect the heater. Main-panel breaker doesn't trip? Its the heater or heater circuit. Breaker trips? Leave the heater disconnected and try disconnecting the pump or pumps. Breaker still trip? Likely a wiring problem. Breaker doesn't trip, new motor or pump time.

It may be easier to start by replacing the main-panel breaker first, just to be sure. They're not that expensive, unless it is a Zinsco.

Your signature says you're "in the industry". Is that true?

 

[parkerma]

Your signature says you're "in the industry". Is that true?

Not sure why it says that or how to change it. Clearly not in the industry

 

[Griswald]

If the main breaker trips instantly, you've got a dead short somewhere...or a bad breaker. If you replace the breaker and it still trips, call an electrician.


Or call the fire department and have them get ready.

 

[RDspaguy]

I'm pretty sure @parkerma thought I was talking to him, not you, so his response was about himself and to me.

the main breaker trips instantly, you've got a dead short somewhere...or a bad breaker.
You are correct. But in a portable spa the pumps are independently fused, the heater cannot physically short without also faulting to ground (and tripping the gfci breaker), and the control system would literally catch fire before it tripped a 50 amp breaker. Which leaves only the wiring as a source for a short. The OP did not mention changing any wiring until troubleshooting the issue, so (barring some freak occurrence) it must be a bad breaker. I've been fixing spas for 26 years, and would not hesitate to replace that breaker. 99% that's it.
I will also mention that a bad breaker often will not trip unless it is under a load, so the fact that it stays on with this or that disconnected does not mean it's the disconnected component that is bad, it just means you've reduced the amp draw enough to not trip it. Dead shorts that trip main breakers are so rare with spas as to be practically unheard of. I've never seen it happen with a gfci breaker also in the circuit.

Right, that is what i am going to do first.

Replace the breaker. If that's not it, pm me your address and I'll mail you a refund check if the $50 for the breaker is the issue. Do yourself a favor and don't go down the rabbit hole suggested by poolman unless the new breaker also trips. Not only will you waste time, you are likely (under the right circumstances) to misdiagnose the issue when you disconnect enough stuff that the breaker holds, and go buy a pump or heater you don't need.

you replace the breaker and it still trips, call an electrician.

He probably won't help you. To an electrician, your spa is an appliance, and his job stops at the main lugs on the circuit board. Rarely will a residential electrician touch anything past that. He's as likely to fix your AC or microwave. Now, find an electrician who's also an AC guy, and he'll probably do it, as would an AC or appliance tech.

 

[parkerma]

You are correct. But in a portable spa the pumps are independently fused, the heater cannot physically short without also faulting to ground (and tripping the gfci breaker), and the control system would literally catch fire before it tripped a 50 amp breaker. Which leaves only the wiring as a source for a short. The OP did not mention changing any wiring until troubleshooting the issue, so (barring some freak occurrence) it must be a bad breaker. I've been fixing spas for 26 years, and would not hesitate to replace that breaker. 99% that's it.
I will also mention that a bad breaker often will not trip unless it is under a load, so the fact that it stays on with this or that disconnected does not mean it's the disconnected component that is bad, it just means you've reduced the amp draw enough to not trip it. Dead shorts that trip main breakers are so rare with spas as to be practically unheard of. I've never seen it happen with a gfci breaker also in the circuit.


Replace the breaker. If that's not it, pm me your address and I'll mail you a refund check if the $50 for the breaker is the issue. Do yourself a favor and don't go down the rabbit hole suggested by poolman unless the new breaker also trips. Not only will you waste time, you are likely (under the right circumstances) to misdiagnose the issue when you disconnect enough stuff that the breaker holds, and go buy a pump or heater you don't need.


He probably won't help you. To an electrician, your spa is an appliance, and his job stops at the main lugs on the circuit board. Rarely will a residential electrician touch anything past that. He's as likely to fix your AC or microwave. Now, find an electrician who's also an AC guy, and he'll probably do it, as would an AC or appliance tech.

Yes, i thought you were talking to me... i am just a homeowner, but i know how to replace breakers, wire a GFCI, i replaced my circulation pump, heater, etc. i am competent in those areas, just trying to work backwards.

 

[phonedave]

Yes, i thought you were talking to me... i am just a homeowner, but i know how to replace breakers, wire a GFCI, i replaced my circulation pump, heater, etc. i am competent in those areas, just trying to work backwards.

Follow what @RDspaguy suggest - replace the breaker. As he said, it is either a bad breaker or a dead short. Now, bad breakers are rare, but so are dead shorts that just "appear". Also, given the fact that there is a GFCI in the circuit that does not trip, it points to a breaker issue and not a short.

If you have a Volt/Ohm meter, that would help things along. You could sectionalize things and if it does somehow lead back to the tub, that is what you really need before you go replacing components at random.

 

[parkerma]

Thank you. I am running to home depot later today to get a breaker. I will update once installed.