Hello All,

I have a very odd outage here. For some background, last year in one of my bedrooms (1958 Cape Cod), which I know is on a 15A circuit the power went out in a strange way. I say strange, because we've known that when everything is on and if my wife uses her hair dryer while the little room heater is plugged in and on, that it would blow the breaker. Ok, easy enough, we reset.

Last year about this time however, under the same circumstances, the power would cut off as if it WERE the breaker but it was not. And more strange, after several hours, it turned back on without notice. Did that twice and then an entire year passed. So, to be clear, breaker wasn't blown. No outage anywhere else in the house, and it just came back on.

Ok, fast forward. Yesterday the power went out on that same circuit and now 24 hours in, it did not turn back on. In the meantime, I began troubleshooting this morning. I thought I isolated things down to a bad breaker switch.

The reason - When checking power from the others on the main bus, there were two that registered no voltage. Oddly, a continuity check showed good though. So, I replaced those two with new ones and nothing.

So, in the stack that I'm focused on, there are 4 (all 15A). When I check the first one, it shows like 246V~, the second one nothing, the third one, 246V~, and the fourth one nothing.

Not even quite sure the first two show so high.

Apologies for the lengthy initial note - just thought the insight might be helpful.

Any ideas?

Eric

 

Very strange.... not really.

It sounds like you are working with a multiwire branch circuit. That's where two circuits on two adjacent circuit breakers share the same neutral.

If you are seeing voltages of 240v at standard receptacles then you may have lost the neutral.

The circuit design is easy. Finding the problem is not. First you need to confirm at the panel if the circuit you are working with is on the red or black wire of a three wire cable.

In the mean time.... be very careful what you plug in as it may become damaged on 240v.
Probably best to not use those receptacles right now.

 

Hi Pete,

Thanks for the quick reply. I'm not getting the 240 at standard receptacles, just on the two breakers I mentioned.

I've taken a picture this time (didn't realize I could last time). If you are thinking the box looks old, it's because it is. I believe the original for the house. There is a larger one that contains about 6 times as many.

I've number the two that have the high voltage. The second and fourth in sequence are the ones registering nothing.

So, what next? lol.... Eric

 

I hijacked your panel picture.

I misunderstood your problem. I thought you were finding 240v at receptacles. That's good. No need to get involved with a MWBC.

I added A and B to your panel. Every other row is a different leg.
You check for voltage from each breaker to ground or neutral.

 

Hello,

I could swear I saw the name Pete somewhere. Ha. Anyway, so, are you asking me to check the voltage or just describing how to do it?

And second, what should I be looking for at this point?

Just from a background perspective, while i wasn't too familiar with this split thing, I have some decent experience in wiring and electronics repair.

So - looking over the diagram and checking voltage while I wait.

Thanks,
Eric

 

I added the labeling to the panel to illustrate what you see when measuring voltage there.

In your 1-3 slot is a two pole breaker. There should be 240v between terminals.

I see your 1 and 2 now. 1 is breaker 2 and 2 is breaker 4.
Between the two breakers you will measure 0v. Measure from each one to ground and you should see 120v.

By the way.... that is a Square D QO panel. Even old....... good stuff !

 

Thanks,

Ok - so every single one is right on 120V.

Now what? I recognize that means, coming out of the box is good.

Eric

 

Ok... good.

Now you need to find out everything that is on the problem circuit. Since everything starts at the panel I usually pick the closest device to the panel and start there. You are checking for 120v between black and white. A non-contact tester cannot be used for this as it will not show loss of neutral.

You may need to check every device in that circuit. If you find wires pushed in (back stabbed) to the back of the device.... move them to the screw terminals. The push-in connections are nine out of ten times the cause of the problem.

 

Ok....

So, when you say devices, I presume you mean every outlet serviced by this circuit?

Understand the backstabbed versus screws...Roger.

I will get to testing.

So, the presumption here is that one of these babies along the way has a loose connection or otherwise has lost the connection right?

Eric

 

That is correct. With age.... the push-in connections lose their tension and allow the wire to heat up and go intermittent to the point where the circuit is completely open. It can happen on the hot or the neutral side.

Devices = receptacles and switches.

 

Yes, and remember an outlet can be a receptacle, light, or switch and all wire nuts should also be redone.

 

It's not good that you are repeatedly overloading a circuit enough to trip the breaker.

Are the heater and the receptacle where your wife uses her hair dryer located in the same room? Maybe using the same receptacle?

A 1800 Watt hair dryer will pull 15 amps by itself at 120 Volts. Add a resistance type portable heater, (probably another 1800 watts at least) to that and you can severely overload a #14 copper conductor.

Remember...Watts divided by volts equals amperage. Your heater and hair dryer will both be rated in watts, so you can add the two numbers together and divide that number by 120 to see what the total load (in amps) that you're putting on that 14 ga. circuit. Electrical conductors are rated in amps.

It may take a circuit breaker a little while to trip on a over load (verses instantaneous trip on short circuit), so that 14 ga. conductor could be getting pretty warm inside your wall before the breaker trips. I would seriously consider installing a new 20A circuit dedicated specifically to the Bathroom receptacle, if that's where the hair dryer is being used.

 

The heater needs a dedicated circuit too. If you only put in one I'd suggest for the heater since it is a bed room but two circuits would be even better. O/P wrote:

 

"last year in one of my bedrooms (1958 Cape Cod), which I know is on a 15A circuit"

Missed that.

 

All,

Appreciate the responses. To the gentleman that mentioned repeatedly blowing a breaker - I probably should have put that in perspective. That probably only happened 5 times over 11 years. I was just pointing that when it happened it was accidental (oops, forgot to turn the heater off) and on those occasions, it was a breaker reset.

Since the house is old, it's basically only outlets and switches since they didn't seem to place center ceiling lights in rooms.

That just means a lot of lamps around the house.

So, I've essentially gone through and pulled every outlet out, pulled it from the wall, inspected the wires, ensure they were tight, and put them back in. I have not found a single wire loose.

Also, in case GFCIs crossed your mind, I have one of these in the restroom on this circuit. That was one of the first things I checked. Can't really reset it without power but in checking, it has no power even reaching it so I suppose that doesn't matter.

It's really kind of strange because this circuit controls the master bedroom, a side small room, a couple outlets in the kitchen (which shares a wall with that small room), and three outlets in the bedroom above it.

I'm really at a loss at this point. My guess is the next comment will be to say, Houston, we have a problem inside the walls.

Eric

 

Did you check for voltage when you had each one out ? You need to.

Nah.... pretty rare to have problem in the wall.

 

Did I check voltage? lol Yeah - none. Not to be sarcastic, but that's what I expected to see since the switches and outlets aren't powering anything at the moment. Now, there's some nominal stuff, like .037 type of readings.

In the kitchen I do find it odd that in two switch housings, I can have the left one work, and the right one not. I suppose if they come from different sources, maybe not that odd.

And then, another that has two outlets and two switches and the two outlets work, and one of the two switches. Now, mind you one of the two switches is the garbage disposal which seems to be on a separate line.


Eric

 

Although it's not very common to find two circuits in a switch box it does happen...... especially in a kitchen like you found out. You may also encounter two circuits when working with three way switches since the power can come from either end.



Usually the problem is between a working receptacle and a non working receptacle.

Here's exactly what I do.... I go thru and find everything that is out on that circuit. Then I turn the circuit on and it stays on while I test. I use a non contact tester to check for hot. If I don't find anything hot then the problem is between the first receptacle on the circuit and the panel. This is rare. Usually I'll find a few working receptacles on the problem circuit and then a bunch dead. If I do find hot I'll go to each receptacle until I lose it. If I find hot at all the receptacles then I know I have an open neutral. I look at the device that is closest to the panel and check it for neutral. That can be done with a voltmeter across the white and black. Then I'll go from device to device checking hot to ground. I'll find most problems in under an hour.

 

Hi Pete,

Good run down. I am pretty sure that I do not have ANY hot ones on the circuit in question. In one of the kitchen ones, I could also clearly see behind the switches, two sources of power. The working one, the wires came straight out of the wire housing (which happened to be the old fabric type covering). The second switch had a difference source coming from a bundle of wires - oh and this one how red, white, and black (the non working).

The other one I can't say for sure but they are within 3 feet of each other, perhaps both of the non working ones were on that bad circuit. They are the most distant from the main bedroom.

So, I guess I was just not suggesting that I had some hot ones on the bad circuit - I believe every single thing on the circuit is dead.

I'm looking over your diagram to see if I understand how to do what you are saying.

Eric

 

When a house is wired...... the basic circuit wiring starts at the panel and goes to the closest point whether it's a switch or receptacle. That's the place to start. Usually the furthest point from the panel is the end of the line.

As you work thru the circuit..... if you find only one cable(two wires) on the device..... the problem is not there. You are looking for a cable in and a cable out.... at least four wires.

It's important to know everything that is dead on the affected circuit.

 

Well, that's an interesting new detail on the 2 wire/4 wire thing. Makes sense. I think that means that if a 2 wire then it would terminate there, right?

However, as you describe things, the kitchen switch would likely be that first point. I noted in the basement where it goes up to where I believe is that kitchen wall. The line has power in the basement though.

Eric

 

Yes.What are the wires and connections at the switch?

 

Hello,

Thanks. So you asked what the wires were on that switch. I'll have to go remove the plate again and just send a picture so you see definitively BUT, there were 4.

Red, white, black (I think two blacks).

There was no power on either though.

Eric

 

And in the switch box. Leave the switch connected but pull it out so we can see all the wires and connection.

 

Thanks Ray,

It will remain attached. Wouldn't be too helpful not. lol

So, I will be sure the picture shows the whole box, both switches pulled out to the side a little so you can see.

I should be taking today off to work on this. Daylight is becoming a premium this time of year.

Eric

 

Ok, so I've attached the photos I said I would. I was going on memory. Looks like each one has three wires.

The one on the left is functional. The one on the right is dead.

The one on the left appears to have a separate source than the right.

Let me know what you think.

In terms of proximity to the breaker box this would be closest. All other dead things would be behind me as you face this outlet. Behind me and above with the breaker box being in front of me and down in basement.

Eric

 

Both switches appear to be three way switches. The one on the right looks like it's at the end of the circuit. Look carefully at the cable that connects to the right switch. Do red, black and white come out of one cable and go directly to the right switch ?

 

Thinking about it, I did know they were three-way, being each of those have an alternate switch that does the same thing. So, the one on the right. also has a switch opposite the room in kitchen that both turn on and off the kitchen ceiling light. (Neither of which work)

I can tell you that the way the wiring is inside the box, the left one has the cable shown, while the right, the wires just appear - meaning, I can tell if they come from the same cable. I'll try to get a closer look.

Eric

 

Hey there,

This picture shows it pretty detailed. What do you think?

Looks like two sources for the right one.

Eric

 

I can see a lot going on in there. Can you check the red/black wire with the red wire nut for power ? Check it from the connection to ground.

It looks like there are 2) three wire cables and 1) two wire cable involved in this circuit.

That box must be crammed with wires.... which is typically found.

 

Just checked. No power at the red/black.

Eric

 

No power there.... if you don't find any power on any screws of the right switch then power is not getting there and is interrupted elsewhere.

 

I got a better picture too. I also checked the white wires for power. none.

Is that ground supposed to be capped off for some reason? Just noticed that.


So - power not reaching here.....uh oh.

Eric

 

I thank you for all your help out there. Looks like we are running out of steam here on options but I wanted to share just a bit more. The picture here, although I realize doesn't say much, is of the outlet just 2 feet away from the other one (around the bend). The one we've been working is about a foot or so from a corner and this being right around the corner.

The two outlets you see on the left are hot. The switch in the middle is dead, and the switch on the right is hot (garbage disposal). The garbage disposal is definitely on another circuit.

The switch in the middle - I'm guessing is on the circuit in question and has just two black wires connected.

The to add a bit more. On the opposite side of the kitchen there is one more switch that controls a dining room light that is dead. Not sure if this is important (yet) but within just a few inches is a power outlet that IS hot.

I do not know yet if this has any significance until I turn off some breakers and see if by chance it's on the same one. If so, there might be some slim possibility that that could be the first in the circuit. It's essentially located about the same distance from the box....perhaps a tad closer.

Now, mind you, there are a number of other outlets in the kitchen that are perfectly fine and I know from my years there that they are definitely not on the same circuit.

NOTE: If you are wondering where the picture is, it won't seem to load from work. But, it has three devices, from left to right: 2 AC outlets (standard top and bottom), to it's right, a single switch, and to the right of that, another single switch (Disposal).

Eric

Eric

 

Hello again,

I hope you haven't quite given up on my problem just yet but understand if you have run out of thoughts.

So, I went through that old box again, shutting down every breaker and noting the impact.

Number 2 on the right side of the box had no impact on or off so I have to think that is the correct one. Not perfect though because there were a couple on the left that seemingly had no impact. I am going on the fact that I distinctly recall having to reset from the right.

Now, in the attached picture, this is the first device I think after looking things over. First from the box and furthest from the main bedroom affected. What's weird is this switch (powering a ceiling dining rm light) does not work, yet when I use my non contact multi meter it shows power. I'm a little confused because even turning off number 2 does not stop that power.

On that right switch of the lengthy discussion from last night, shows clearly dead with the non contact meter.

I'm freaking baffled here.

Eric

 

That is the main purpose of a non contact tester, to confuse people. Just don't use one. Use a multimeter, preferably analog.

The circuit in your photo is a switch loop. The power for that is at the light not there.

 

The white should be the hot to the dimmer switch. At the fixture there should be a white spliced to a black or red.

 

Ok, well that threw me off a bit that I shouldn't have a power reading there. As the pictures shows, looks like a white is spliced to a red.

With regard to the non contact thing, I certainly don't use that in place of a multi meter but to go down the length of a wire in the basement or just hover over an outlet it seems to work. Particularly when it shows the non working ones as non working. lol

But agree, it can also be confusing at times.

Eric

 

You just mentioned a working receptacle near where you are. Is that on the same circuit ?

You should know every location that is on the problem circuit. Ignore any live device that is not included in the problem circuit.

 

Pete,

No. It's not working but was getting a solid reading using the non contact thing, yet no noted power and the light it controls does not work.

Eric