Breaker for pool pump tripping occasionally

[ard]

Any insight into why my 40 amp breaker for my Jandy pool pump trips periodically?

It does not trip instantly when the pump starts and I noticed that it trips more often when it is hot i.e. greater than 80°F outside than when it is cold or when it rains. The control panel itself is enclosed and faces north so it’s hard to get any sun exposure and does not become very warm. I once had a hot tub where the electrical wiring had been poorly done. Possibly when the lines were pulled the insulation chafed on the conduit, and every time it rained, the hot tub would trip immediately. This is not the case here. The filter pump will run for several days and then suddenly trip.

As much as I dislike throwing parts at a problem, I may swap out the breaker to see whether it is defective, but since the problem occurs, only intermittently it will take some time to know for sure and I would love to perform better diagnostics.

TIA

[Mark Howard]

Is that corrosion on the breaker lever?

[billybek]

Does the pump cycle or does it run continuously?
Have you checked the amperage of the running pump?
Could be a ground fault.
How is the pump seal? Weeping or throwing water?

[908/930]

That is a 220v 20A breaker, not 40A. Breakers do age, I think the thermal strip inside gets old.

As billybek said, check the motor amperage, could be bearings getting old also.

[ard]

Originally Posted by Mark Howard

Is that corrosion on the breaker lever?

Good eye. I’ll have to check.

Also how do I check motor amperage? Disconnect the breaker and put an ammeter in line then start the pump? The installation is about eight years old.

[ard]

Originally Posted by billybek

Does the pump cycle or does it run continuously?
Have you checked the amperage of the running pump?
Could be a ground fault.
How is the pump seal? Weeping or throwing water?

The pump cycles as in it runs about 6 hours a day.

The pump seal looks good visually

[stomachmonkey]

I have the same problem.

Pool was only built last year but the breaker it's tied to in the panel I believe has been there unused from when the house was built so maybe that's it.

Thanks for the tip.

[Bill Douglas]

a 40 amp breaker is a very big breaker. I don't even have one that big for my welder. Even 20 amps is big for something like that.

I don't usually recommend "Getting the man to look at it" but with all that water around, it may be the time to accept defeat and get a good electrician to look at it.

[Jeff Hail]

If your not comfortable or experienced working inside a service panel call an electrician.

Start with replacing the breaker. If its tripping with elevated temperature good chance its aging out. The cycling of the pump motor can wear a breaker over time. How does the throw feel and the engagement of the breaker compared to the one for the booster below it? Same feel, a bit looser, does the engagement feel firm when switching it from off to on?

Does the ground fault test and reset function work properly?

The pump motor has a thermal protector and the pump would cycle on and off it were the motor getting hot (it sounds ok).

Any sizzling sounds in the breaker switching from off to on with the pump set to run?
Check that smudge, wipe it with your finger and see if it has a odor to it such as english car wiring loom. Put your nose up to the breaker and see if you detect anything?

Visually check the hot bus bars that the breaker straddles on in the panel when you remove the cover, look for arcing of the contacts.

[1990C4S]

Originally Posted by billybek

Does the pump cycle or does it run continuously?
Have you checked the amperage of the running pump?
Could be a ground fault.
How is the pump seal? Weeping or throwing water?

This.

[greglepore]

Everyone here covered it mostly. GFI breakers tend to age/fail more frequently than regular breakers. It could also be a failing motor. The thermal limit should trip at the motor before the breaker trips but I've seen them where after the limiter cools enough to restore power the bearing itself is still hot enough to present enough extra start load to trip the breaker. You wouldn't perceive this as "trip on start" unless you knew the motor was heating enough to trip the limiter.

[DavidI]

My main pump was doing the same thing a few months ago (Pentair Whisper Flo approximately 20 years old). I did some research and found several videos on YouTube that referred to the possible culprit as the capacitor. I replaced it ($12 on Amazon) and it corrected the problem.

https://www.youtube.com/watch?v=xk3kVK1K7N8

Good luck, David