Breaker trips intermittently


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Old 10-09-18, 12:19 PM
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Breaker trips intermittently

My pool pump and heater, which total just about 15A, are on a dedicated 15A line.
From time to time, the breaker will trip, and keep on tripping every time we turn the pool on. But once it stops tripping, it won't trip again for months.

What could be causing this behavior, and how do i fix it?

Several electricians have looked at it but had nothing to suggest. One did suggest replacing the breaker, about two years ago, and the pool then worked fine for a while--but it did the same thing whenever we coaxed the old breaker to behave.
 
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Old 10-09-18, 12:29 PM
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If the pump is starting up with some head pressure it will draw more current. This might cause the breaker to trip sometimes. What is the information from the pump nameplate?

Other thought is maybe the hot surface ignitor on the the heater is causing total draw to exceed the limit occasionally. Do you know the electrical requirements for the heater? It might just be that these two equipment draw too much power for a single circuit.
 
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Old 10-09-18, 01:44 PM
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I don't know what head pressure is. If you mean the water pressure, the pump is about 18" below the pool surface.

Pump is 1 hp, 3450 rpm, rated 15A for 115V, 7.5A/230A. I don't know what the pump draws, but the manual says to u se AWG #22 wire for runs up to 30', AWG #20 for longer runs; so it can't be drawing much.

This adds up to a nominal draw >15A, so I wouldn't be surprised if the breaker always flipped. But it doesn't, so there must be some leeway in the system, either a tad more than 15A on the breaker or an actual load of less than 15A at the pool. And it ran without flipping for years; now it will flip every time for a week or two, then miraculously start working for a few months.

So what could be the extra factor that trips it?
 
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Old 10-09-18, 05:23 PM
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I don't know what head pressure is.
Head pressure is the pressure at pump's outlet. If there is high pressure pushing back on pump's outlet, the pump requires more current to start. Once the pump starts rotating, it does not have to work as hard.

Does your pool heater turn on as soon as you turn to pool system on or does it have a flow switch?
If it doesn't, adding a flow switch or putting some sort of delay timer might work.

If you have conduit running to the pool by any chance, it might be best to pull 12 AWG wires and them on 20A. Or maybe just pull additional 14AWG wires to add second 15A circuit and put the pump and heater on separate circuit.
 
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Old 10-09-18, 06:55 PM
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A 15 amp pump on a 15 amp circuit is not going to work very well. You should have #12 wire and a 20 amp breaker.
 
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Old 10-09-18, 07:16 PM
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If the pump is really rated for 15A, then it should have dedicated 20A circuit for the pump only.

rated 15A for 115V, 7.5A/230A.
I couldn't figure out what the op was trying to write here and I assumed it has 15A cord and the pump pulls 7.5A.
What is 230A supposed to mean?
Since the pump calls for 22AWG wire, it should not be pulling 15A.
 
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Old 10-09-18, 09:12 PM
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says to use AWG #22 wire for runs up to 30', AWG #20 for longer runs
That was probably supposed to be #12 and #10.
 
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Old 10-09-18, 09:15 PM
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Does the pump call for 22 or 12 gauge wire? #22 is phone line size. This is even smaller than thermostat wiring.
 
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Old 10-10-18, 10:42 AM
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Head pressure is the pressure at pump's outlet. If there is high pressure pushing back on pump's outlet, the pump requires more current to start. Once the pump starts rotating, it does not have to work as hard.

Pool heater has an LED control panel that turns on when power does, but it does not actually ignite until pump has been running a while. It shuts off the gas and shows "Lo" if pressure is insufficient due to low water level.

I don't know how big a job it is to pull new wires: Pool equipment is about 20' from the house and ~30' from the breaker box. I think upgrading to 20A wiring ansd breaker would be safest, since the motor itself is rated 15A--or maybe it would be more cost-effective to replace the motor wwith a 3/4-hp model--I had one 20 years ago and it seemed to work OK, though I get better circulation with the 1-HP.
 
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Old 10-10-18, 11:44 AM
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#22 is for the gas heater, not the pump. However, the cord going to the heater loos kinda thick for AwG #22
 
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Old 10-10-18, 04:57 PM
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If the pump really is 15A, then you need to put it on dedicated circuit.

If you have conduit running all the way to the breaker, then it wouldn't be too hard to pull additional wires.
If not, you may have to cut drywall here and there.
 
 

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