baffeled

January 3, 2009 4:29 AM

i had power go out to a portion of the house because a pump was running and pushing against water that couldnt move because ice was in the outlet pipe. i turned off the light switch and shut the pump off. i came back 4 hours later and there was no power from that switch. it was 12 degrees out. 2 days later it warmed up and all of a sudden i had power again. any ideas, i am worried
posted by blizzardm17 to home & garden (11 comments total)

call an electrician. this could be some weird electricity mystery that's perfectly harmless, but it could also spell big trouble. when i had problems with my electricity fading out & then back on--sometimes minutes later, sometimes hours later--i had an electrician go through the house. he thought it was a faulty wire & started replacing the wiring, one room at a time. when the new wiring shorted out on him the minute he flipped on the breaker, he knew it wasn't the wiring at all. he did a tele-conference with his master electrician mentor in another state, then called the local utility company who sent out an engineer. turns out that the neutral coming into my house was compromised--the protective wrap around the wire had a small tear & water was getting in there (or something like that). after he replaced (or repaired, i can't remember) the neutral line it was fine & things were back to normal. a little pricey, perhaps (i think it cost me about $500 to replace/repair the neutral, plus what i'd already paid him to run new wire in 2 rooms), but it beats a house fire.
posted by msconduct at 6:07 AM on January 3

Might be a feature of the breaker in your house, that it might have some kind of reset feature for certain types of overloads.

Or someone else reset the breaker manually?
posted by gjc at 8:31 AM on January 3

Power going out either means the breaker trippped or something bad happened - like some component on that circuit was drawing more power than it should have, and continued to do so!

If the breaker didn't trip and this happened, I'd call an electrician ASAP, for fear of a wire overheating and burning the place down.

If the breaker tripped, and it's not tripped anymore, I would assume someone reset it.
posted by zippy at 10:27 AM on January 3

Your description of the problem is ambiguous. (Go back to square one and describe the problem again.) What you are describing makes no sense.

What pump? Plugged into a light socket controlled by a wall switch? Why do you have a pump on a switch and in a location where it will freeze? Has it ever worked properly before?

".. no power from that switch"? Does that mean when you reactivated the switch that you used to control power to the pump that the pump did not start or does it mean that the entire circuit (presumably including other lamps,etc.) did not work? If the pump did not start, how do you know that there was "no power from that switch"? Did you measure it with voltmeter or are you just assuming that since the pump did not start, it was not powered?

I have many suggestions for troubleshooting stuff like this, but really, spend some time describing what you have, what you did, and why you are confused and you'll get a better response. If you think you are confused, imagine what we feel like trying to read your mind.
posted by FauxScot at 11:06 AM on January 3

the light switch inside the house controls first a motion light and then down from that a gfi outlet that a sump pump was plugged into. there was ice in the pvc outlet for the sump pump so the pump was continually pumping and starting to overheat. i was sleeping at the time and was not aware of the problem. i heard the pump running so i shut the light switch. the temps were about 12 with wind chills below zero. when i went to turn the switch back on 4 hours later the light was no longer working and the gfi which is downstream from the light was out. 2 days later it warmed up to 47 outside and the light jumped back on and i was then able to reset the gfi that the pump is plugged into. i know there was no power because the little motion detector sensor that blips before the light comes on was not blipping. i didnt use a voltage tester though. the rest of the lights and power in the house was working without any problems. in fact the light switch that controls the area that went out has two switchs in it . the bottom switch was for the light outside and the gfi outlet. the top switch is for the living room lights inside the house and they were always fine. please help. for now the pump is not plugged in but there is power to the light and the gfi is live.
posted by blizzardm17 at 1:00 PM on January 3

the motion light and the pump are outside the house just outside the door. the light switch is inside the house right behind the door. thank you
posted by blizzardm17 at 1:02 PM on January 3

OK... thanks blizzardm17... that helps a lot.

The circuit (if wired properly) looks like this:

house supply wiring (at panel)
panel circuit breaker
distribution wiring to outlets ((white (Neutral) and bare wire (ground)).
switch (which switches the Hot (black) wire to the outlets
distribution wiring to the light outlet and the GFI
GFI outlet
sump pump

In the sump pump, there is probably a thermal overload switch

I can't imagine (if this is the wiring) that any pump issue would affect the light, UNLESS you are running either flourescent or compact flourescent lamps, whcih might not come on if there were a low voltage brownout condition. Such a condition might be present if the GFI were still operational AND the sump pump rotor was locked, whcih would present a larger load to the line until the sump pump thermal overload kicked in and took the pump off circuit.

Since it was frozen up, and since it was 12 degrees, there is a good chance that this circuit suffered low voltage due to high load, but not high enough to trip the panel breaker.

That's about the only scenario I could imagine that might explain the intermittent symptom that you have. If you are using standard incandescent lamps, they'd show up as very dim, but flourescents or CF might not come on at all under low voltage conditions.

Testing this would be a bit of a challenge. You'd have to get the locked-rotor motor load and see if it was large enough to cause voltage droop on this line without exceeding the current rating of the panel circuit breaker.

The GFI would trip if the hot/neutral currents differ by more than a very small threshold amount, but not if the currents were high but symmetrical.

Anyway, it's a potential explanation.

Does any of this fit your circumstances?
posted by FauxScot at 1:55 PM on January 3

Perhaps the light going out was coincidental with the pump going out, and was caused by a loose bulb? See if it's screwed tight in the socket.
posted by zippy at 2:54 PM on January 3

the bulbs are spotlights and they werent an issue. there was no power going to the light at all because the little sensor light that trips the real lights on was not working. could the overload have caused a wire to partially burn but become operational later . someone did look at the switch that turns the light on and said the wiring at the switch was good. could that wiring be good and wiring furthur back towards the circuit panel be burned. can i test to see if the wiring is okay. thank you all for helping me.
posted by blizzardm17 at 3:58 PM on January 3

My theory is out.

Not likely that you have an intermittent of the type that you describe that would be traceable to a 'partially burned' wire.

If this isn't a repeatable failure, it falls into a difficult to troubleshoot category (i.e., you can't fix it if it won't stay broken).

I'll give it some more thoughts overnight.

Interesting problem.
posted by FauxScot at 4:22 PM on January 3

One item to check to make yourself feel better....

Find out what the breaker trip load is... (i.e., if it's a 20 Amp circuit.) If you are alone and want to do this, plug a radio or tv into the outlet, turn on the volume high enough to hear while you are way back at the panel, and trip breakers until it goes off. Look at the breaker and see what it says. In all likelihood, it's 20 Amps.

Then, get two electric space heaters and /or a 1500 Watt hair dryer. Go plug them in all at once to the outlet where you had the radio and turn them on. Verify that the breaker eventually trips.

If not, call an electrician to replace the malfunctioning breaker. If you can't get the load up high enough, add a toaster to the group. 1500W is about 12.5 Amps.

If it trips, then the circuit is protected properly and what I would do is document the exact circumstances that relate to this particular event as the first observation in a longer term monitoring of the symptom. If it never happens again, it's what is called an 'unverified failure'. Otherwise, it's an intermittent condition that will take a while to collect enough observations to allow a pattern to emerge and allow the problem to be identified, located, and resolved.

If you are a little paranoid, having an electrician look at this particular circuit seems wise. Hidden wiring problems, particularly those involving safety or protective circuits are troublesome and can be potentially lethal and/or fire hazards. Better safe than sorry. ( My office burned to the ground in November, and I suspect rodent wire damage, though it has not been verified.)

Good luck. Wish I had some better ideas for you, but I do think that testing is a good way to start.
posted by FauxScot at 2:18 AM on January 4