Check out some similar questions!

Up_the_creek2 · Mar 30, 2012, 01:22 PM

We have a new well pump installed . Since then the well pump trips the breaker only in the early morning hours when there is not a big load use on the pump . It does not trip in any heavy rain storms " under ground short you would think would increase. Any ideas? The pump is on its own 20 amp new square D breaker

speedball1 · Mar 30, 2012, 02:10 PM

Has anybody ever put a Amp-Probe on the wires when the breaker trips to see how many amps the pump's pulling? Back to you, Tom

Up_the_creek2 · Mar 30, 2012, 02:16 PM

Why would this only happen late night when water would not be running? Never happened when we would fill the hot tub or pressure wash all day. One would think this would happen at any time. This has been like this for 2 years and never filled the breaker when we were up only at night.

jlisenbe · Mar 30, 2012, 04:08 PM

Is the pump the only thing on the breaker? That is probably the case, but stranger things have been known to happen.

More possible, do you have a water filter on the same circuit? Many filters are programmed to backwash at night.

Up_the_creek2 · Mar 30, 2012, 08:18 PM

Pump is only thing on its own circiut, water filter/ water softener / acid neutralizer in line

speedball1 · Mar 31, 2012, 05:39 AM

What size breaker is on the line?

the breaker only in the early morning hours when there is not a big load use on the pump

Could something be setting up in the pump as it sets idle all night that puts an load on the starting coils? Just wondering. Tom

jlisenbe · Mar 31, 2012, 07:37 AM

He said it's a 20 amp. But, as Tom suggested, I think measuring the amperage it's pulling would be worthwhile. Breakers are only supposed to run for long periods at 80% of their rated capacity, so that would be 16 amps on each leg for your pump. The 20 rating is just for short surges.

speedball1 · Mar 31, 2012, 07:47 AM

He said it's a 20 amp.

Sorry I missed that. My bad! Do you think swapping the breaker for a 30 Amp would solve his problem? Let me know, Tom

jlisenbe · Mar 31, 2012, 09:00 AM

If I was him, I'd ask an electrician about that. You don't want a breaker that is too large for the wire. According to the website below, a 30 amp breaker should have 10 gauge wire. Wouldn't surprise me if 10 gauge is run to the pump already, so if that is the case, then moving to a 30 amp breaker might be do-able.

http://groverelectric.com/howto/08_H...%20Wattage.pdf

Still doesn't answer the mystery of why it only happens at night. That is really strange. It will fill a hot-tub... no problem, but kicks off at night when it is seemingly not being used. I still would look at the backwash setting for that filter and see when it cut's on. If you can get a time for when it backwashes, and let's say it is around 2:00 a.m. then I'm getting up at that time (crud!) and listening for the breaker to throw.

I still like Tom's idea about measuring how many amps that pump is pulling.

Up_the_creek2 · Mar 31, 2012, 10:12 AM

Thanks I'll let you know what's up

jlisenbe · Mar 31, 2012, 10:48 AM

Please do. We always like to hear how these cases are resolved.

Up_the_creek2 · Apr 13, 2012, 09:55 PM

We think the problem is solved they pulled the pump and rechecked the new wireing, then replaced the pressure switch at the tank. They saw the one that they replaced had a well Pump switch that had a low water switch on it. We hope that it thought the water level was low and it switched off and through the breaker! Thanks every one this really had me stumped.

speedball1 · Apr 14, 2012, 05:59 AM

Hey Creek,
Thanks for the update. Glad you're all fixed up. Good luck, Tom