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Just grumbling...

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MacGyverS2000

Electrical
Dec 22, 2003
8,504
Getting ready to remodel major portions of the significant other's house, which means messing around in the breaker box. As an electrical engineer I'm fully aware of electrical safety practices, but that also means I'm very nervous about approaching the box because I know what can go wrong (been shocked too many times building high-voltage circuits as a young'un, but they were obviously low current). The house was built the early 70's, and everything looks copper (thankfully). There doesn't appear to be a main breaker in the box, so I'm hoping there's a cut-off on the meter (I'd feel much safer doing that anyway). I'll be doing a lot of work on and off, so I don't want to call the power company each time to shut it all down.

The first change is to move the water heater downstairs, but I'll also be debugging a nagging problem... the power to the bathroom goes out about once a month. With no warning, the lights fail to come on and the outlet attached to the same box supplies no power, and power is restored in the same manner by next morning. It happened two nights ago and the meter shows no power being supplied to the switch, so I'm thinking it's in the breaker box (loose terminal screw?). I don't smell/see any arcing or burning in the switch/outlet box. I love the puzzle, but hate that it's on a high-voltage/current circuit :(

Just wanted to grumble about having to do it, maybe get a few "I was once nervous, too" stories added in. Now that I think about it, some self-learned safety tips would be good to add here, too (maybe easy ways to block off live bus bars while working in the breaker box, etc.).

Dan - Owner
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Turn on everything in the bathroom.

Point an infrared thermometer at the breaker terminals, and look for a hot one.



Mike Halloran
Pembroke Pines, FL, USA
 
Look for a GFI on the same circuit (we have one in the garage that is inexplicably connected to the laundry room outlets as well).
 
btrue, There are zero GFCI circuits (or breakers) in the house, something I will be slowly remedying as I redo each portion. The kitchen comes first, the bathroom will be the third (second being putting in another bathroom in the basement).




Mike, If I can find an IR thermometer here at work I'll try it, but I did not feel any hot breakers when it happened a few nights ago. Shall I assume a hot breaker designates one that needs to be replaced? I know the circuit can get hot if there is arcing. I can run a 1900W hairdryer on high for 10 minutes with the lights on (fluorescents) and see no issue... two days later, flick the light switch in the middle of the day and nothing.

Now, an interesting tidbit of info which I just remembered... my SO says she replaced the four incandescent bulbs in the light fixture with two fluorescent months back and that seemed to mitigate the problem. How true that is I do not know (it happens so infrequently, it's difficult to tell if anything has an effect), but I will quiz her on it some more this evening.


Dan - Owner
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Just take your VOM meter and measure @ the breaker when problem is occurring. If 120ac is present then check @ the switch. Could be bad or dirty switch.
 
I'd be less concerned about a warm breaker than a warm terminal.



Mike Halloran
Pembroke Pines, FL, USA
 
jde, That brings me back to my original grumbling point, and that's taking the cover off of the breaker box. It may seem silly to people who do it all of the time, but after popping myself several times in years past with workbench projects, moving to high-powered stuff gives me the willies... but I'll be biting the bullet soon and doing it.

Dan - Owner
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Check it at the switch if you do not want to remove the cover of breaker box. Just be careful when pulling it out.
 
Since for your bathroom problem you have both an outlet box and a light, I would check the wiring at these points. Inexpensive outlets and switches may have push-in wire-captures and not screw terminals. Power is daisy-chained from one outlet to the next. These can be intermittent killing everything downstream. Also check the outlet for an incompletely stripped wire where the insulation is under the screw head - also a possible intermittent.

Circuit breakers do go bad with age, and I've had to replace some in houses I've owned. The usual symptom is tripping, or lights that flicker - both indicate the breaker is heating from internal resistance. If your bathroom has a ceiling heater on the same circuit, this can pull enough current to weaken the breaker over time.

 
I'm with Comcokid..

The daisy chaining between outlets/fixtures is a really common place for this nonsense to happen. I'd say 90% of the time this is The Problem. It can be very serious too! As it means an undesired resistance in a place that shouldn't have multihundred degree temperature rises. I've had four cases in this house over 35 years. Half of them blinkers and half of them smells. In one case a metal switch cover turned out to be too hot to touch! I'm glad that it wasn't a plastic cover as it wouldn't have been dumping a 100W of heat out of the problem area. That was discovered as a "what's that smell?!?!?" as we walked in from a family outing.


Quit sweating the breaker box stuff! It's easy. If you understand everything, as I'm sure you do. The key is you turn the breaker of interest OFF and then just unplug it. Do all the work you need to, replacing it etc. Make sure it's OFF plug it back in. Then turn it on. You aren't working on anything live. How is this different from unplugging a lamp to repair?! It isn't.

The largest problem is if you bring wires into the box. You must be careful to not let them wander about as they can hit the buses or the other breaker screws etc. Try to always run new wire from say, a roll on the ground up to the breaker box, thru the conduit or knockout to the point of use. That way only fully insulated wire is running thru the breaker box and you're never shoving wires into the box from somewhere.

Keith Cress
Flamin Systems, Inc.-
 
I would start with checking the splices in the boxes and looking to see if they did daisy chain thru the receptacles.

While 99% of all house power electrical contractors love do daisy chain thru devices cause it cheap easy and fast, pay close attention to the neutral!! That is where the problem usually hides in a bad or loose connection / splice, ene under wires nuts being loose and wires not tightly twisted together.

If the house was built in the 70's it was before the code required the use of GFI in bathroom and kitchen and the problem could even be outside the bathroom area. Would recommend that you turn the breaker off for the bathroom and check to see what else goes off with it.


Hope it helps you some,

Roger
Master Electrician
 
Yep,
I agree with smoked and comcokid.
I had a problem at my friends farm in the attic like smoked said. Garbage wiring. Had a hot switch problem in my own house.

If you contact your electrical company and tell them what you want to do, they may let you pull the main meter outside. This WILL shut your box down. However, the meter box usually has a one use only tag thru the locking lever. If you remove this w/o contacting your service provider, they may decide to investigate you. Oh, FYI, do not put the kwh meter back in upside down or it will run backwards! This will GREATLY increase the chance that your local provider may wish to speak to you. :)
If you go insde the meter box, BE CAREFUL, this has the capability of big current! I believe they fuse the local transformers, I dont know. But by the time that blows, a person would just be a puff of smoke and a memory. Please be careful.

Oh, be safe, still check your box with a meter!

Have fun,
Scott

In a hundred years, it isn't going to matter anyway.
 
An unintentionally disconnected neutral can cause a meter to read zero (H-N) even when it's all hot. Keep your wits about you.

Once upon a time I had a reason to make sure that the large allen keys that clamp the 200A wires into the panel were tight (confirm they're tight while live). I used an insulated surface to stand on, clean rubber boots, rubber electrician gloves, tool with an insulated handle, and some quick touches just to make sure. It apparently worked out okay...

 
Tsk tsk tsk... not supposed to post residential Qs here, but you get a pass for being a regular I suppose.

My house (cir. 1971) has no main CB in the load center either, it's outside below the meter socket. No problem with that as long as you know where to go find it in an emergency. It was an "experiment" in the 70s based on the idea that the Fire Dept. could shut down power to your house before entering. Turned out not to matter that much one way or the other; if it was an electrical fire and the fire dept. was already there, the fire must have already started anyway!

Tip;
While it is still working OK, find out which breaker it is by plugging a radio into the circuit and playing it real loud while flipping breakers until the radio goes off. NOTE: may cause you to need to reset your TV station choices and clocks everywhere! Once the circuit is identified, try to also identify all other sockets and light circuits tied to it by plugging in the radio with only that circuit breaker off. No radio = common circuit. To test light sockets, turn every light on in the house before flipping that breaker off, no light = common circuit. Make yourself a map.

Then next time it fails, start at the breaker with a meter to see if you have voltage there. If you do, there is a loose connection downstream from there somewhere. Starting at the closest identified outlet of light switch / fixture, keep testing to see if one of the hot wires is still hot. Work your way towards the farthest identified fixture, thinking like you were the guy having to pull that wire, i.e. the shortest route possible if the walls were still open. IMPORTANT: test by going Hot to Ground, not hot to neutral (explained later). If you have plastic boxes and/or no ground wires (although you should have had a ground wire in the 70s), then get a long length of wire connected at one end to a water pipe. If you get to a box and the hot is dead, the loose connection may be there or in the previous box.

If you get to the end and they all are hot, then you have a lose neutral somewhere. This is actually very common for your symptom by the way, because if it were a loose hot wire you would likely hear sparking sounds or smell smoke. Start the process over but go Hot to neutral until you find a dead circuit. make sure you don't touch the ground and neutral together when doing this check or you may get a false positive.

If any of that makes you uncomfortable or if that doesn't find it, call an electrician. He will have tools to do this faster, but those tools are typically too expensive for occasional use. Don't leave it be, this is potentially life threatening!
 
Do you have a recessed lighting in the bathroom? They collect moisture from the shower and don't dry out. Since they are not in direct contact to the moisture the problems are delayed and so are the fantem self fixes. Bathroom recessed fixtures have a seal which degrades. When the seal leaks, well we all know what steam can do to connections. especially wire nuts. Good luck.
 
poo, no recessed lighting.


j, Thanks for the tips. I started the post more as a place to simply grumble about having to go into the box, maybe read a few first-timer stories and safety tips, but as the posts went on it turned into more of a troubleshooting session for one problem I ran into.




The power was lost again last night, but I had already taken my meter home, so I couldn't check anything. I also learned the switch is a three-way with the mating switch hiding behind the bathroom door (gotta love those 70's architects!). I plan on checking this one, too, the next time it happens. We're taking a trip to Home Depot tonight, so I'll pick up some new switches and a GFCI socket... it certainly can't hurt to replace them, and she definitely needs a GFCI socket in there.

Dan - Owner
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Check the 3-way behind the door. If it is slightly out of position it will create an open. If it is open, you get what you have described. Flip that unused switch back and forth several times to clean the contacts. See if that doesn't clear things up.
 
Another option is to hire an electrician and let him grumble about it while you sit in front of your PC with a beer. He will also have to take any blame should something go wrong with other wiring in your significant other's house.
 
I've already started on the plumbing, going to rough it all in before I cut into the existing pipes. I'll do the same for the electrical, get it all ready with the wire leading up to the breaker box... that way the box is only open for an hour or so and everything is good to go.

I'm surprised no one had any horror stories to share...


Dan - Owner
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You want horror stories I got one.
My buddy's house is 13 years old, 2600sqft, two story.

He requested that the plumber use heavy wall copper pipe. (M?) (L?)(I forget). Anyway nine years after the build the valve for an upstairs toilet starts leaking.. Bad enough that it drops the garage ceiling. Calls the contractor and asks where's that plumber?!?!? "He left the state a few years ago."(brother-in-law) I'll come fix it. He does.

10 years, one month later the hot exit pipe from the water heater starts leaking. He calls the contractor again. Guy comes out and cuts out two sheet rock panels behind and above the water heater, fixes the leak.

A month later another fitting lets go flooding the dining room. Calls the contractor. "10 year statute of limitations is over, sorry don't bother calling me anymore." This requires wall repair and a plush carpet replacement.

Next his wife mentions that the hardwood kitchen floor seems oddly warm. He's busy, doesn't check it out. $400 water bill and $400 dollar gas bill arrive simultaneously. Time to check things. A copper fitting in the hot water circuit with reduction and (4),(four),(IV), outlets has corroded thru and has almost a 1/4" hole in it directing the hot water at the kitchen floor. HE must lay in a warm mud bog under the middle of his house and remove 8 inch insulation before locating and fixing that obtuse fitting and engineer a way to replace it in the center of the four lines coming from four directions.

Since this failure he has 11 more similar ones.

The plumbing contractor(dufus) failed to clean any of the flux off the lines so they are all corroding thru one at a time starting with the hot lines as the reaction rates are higher.

So, if you are using copper clean your flux off and flush your lines properly!!

Keith Cress
Flamin Systems, Inc.-
 
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