Residential intermittent electrical problem

Factual Questions
1

I need ideas please, on a residential electrical problem.

But, in the interest of brevity, and keeping the boredom quotient to a minimum, I’m going to keep my initial description to a minimum.
If, I said that a kitchen outlet(including 1 other outlet on this common wall), was losing power for anywhere from 5 seconds to several minutes, then resuming full power,
what would be suggested as the cause. BTW, the breaker for this circuit shows to
be 20A, and both outlets on the circuit show to be 15A. And, the breaker never pops
anytime during this poweron->poweroff->poweron sequence.

Thank you,

gmak

2

something is broken.

one possibility is a bad/loose connection of a wire to the receptacles or part of the receptacles to itself or passing on the power to the next.

could also be a loose connection at the breaker or a broken breaker.

3

IANA electrician:

I think you should switch that breaker off until you find what’s wrong. A loose connection in the wiring behind the walls could start a fire. But the first think I’d do is look for a switch on that line. Changing breakers is easy to do, once you’ve been given some basic instructions and background information. So if you can do that, it’s good place to start investigating.

Also, how did you determine there was no power. if you have a voltmeter, or even simple circuit tester you may be able to tell if the power is actually off, or there has been a substantial voltage drop, which isn’t good either.

If you don’t have the tools or experience for doing this yourself, get an electrician.

4

It sounds like you have only two outlets that lose power, not the entire circuit. That suggests loose wiring in one of those outlets, with the other “downstream” outlet also being affected. But it’s also possible that the loose wire is actually at an upstream outlet that works, or that a third outlet “upstream” is losing power, but you never use that outlet and don’t realize it.

Agreed that you shouldn’t use any of the outlets with this problem until an electrician (or you, if you know what you’re doing) have identified the cause and fixed it.

5

I’d suggest testing the outlet when you think the power isn’t working. Either with an actual tester or just with some other appliance or a lamp or something. I’d be curious if there’s an actual problem with the outlet or if whatever you’re using has an internal overload switch that’s breaking and resetting after a few seconds…or take the thing that keeps turning off for 5 to 15 seconds to another outlet on a different breaker and see if you have the same symptoms. Is it something with a motor or heating element?

6

Do both outlets lose power at the same time?

And being in a kitchen, is one of the outlets a GFCI receptacle?

7

As has been asked how do you know it is loosing power? Just by an appliance not working? Voltage tester? or a volt meter?

Get a volt ohm meter and test for voltage between the hot and neutral, the hot and ground, and finally between the ground and neutral. Do this while the outlet is working. The first reading should be 120 vac, and 0 for the second and third. If you get good reading using the ohm meter test between the neutral and ground, the resistance should be low. Besure you do not get the hot and ground or you may be buying a new meter.

Retest voltage when the outlet is “dead” If you get 0 volts all three readings then power is being lost. If you get 0 hot to neutral, but 120 hot to ground and 0 neutral to ground your neutral is open. if you get 0 hot to neutral, 120 hot to ground, 120 neutral to ground there is a feed back somewhere.

Start by checking all outlets in the area for propper voltage. Turn the breaker off the the outlet in question and retest. Find every outlet that is turned off with the breaker. Outlet boxex are wired in a “daisy chain” that is the wire goes from box to box. So by looking at the lay out of the outlets that are off you should be able to determine the line. If the problem is not in the first outlet of the run then it is probably not the breaker. Depending on when your house was built and the code at that time there may be a GFIC outlet. If the problem outlet is not the first breaker after the GFIC then the GFIC is in the clear.

When you lhave elimninated a breaker or GFIC outlet problem the turning the breaker off and testing to be sure the outlets are dead. The wiring in the electrical boxes have to be checked. Remove an outlet from it’s box, becareful not to get yoursel grounded. Make sure there is only one hot in the box. Use the Mark one Mod one eye ball and also use one of the wand voltage testers. If more than one hot tulrn of building main to be safe.

Check the wiring to the outlet. Some people make the mistake of daisy chaining through the outlet note if this mistake has been made. If this was done then a loose screw or burnt terminal can cause the problem and is a fire danger.

You are going to need to check the outlet before the problem and after and then the problem outlets.

If you have no experience with electricity then I would sugggest calling in a electriction. Fixing the problem yourself is not worth your llife. And leaving it alone is not worth loosing your kitchen.

Let us know how it goes.

8

Reply to all… First, thanks for all the comments/suggestions.

I was trying to keep my descriptions concise, for a problem that’s not concise.

  1. AFAIK, there are only two outlets on this circuit/breaker.
  2. When the frequented outlet pops, the other outlet pops also.
  3. All(I assume) outlets in this residence are backstab type. About 4 years ago, the other side of the
    kitchen lost the entire wall of outlets. The electrician tracked the failure to a single outlet with
    faulty backstab connection. So, when this current problem on the opposite kitchen wall
    happened, I assumed a backstab fault.
  4. During that 4 year ago electrician visit, he told me that I should move the microware and toaster
    to the other side of the kitchen because they compete with the refrigerator.
  5. So, we moved the microwave and toaster across the kitchen, and have been happy with that
    configuration for the last 4 years. This problem just started in the last month, and centers around
    the use of 1 outlet serving that microwave and toaster. But not always concurrently.
  6. The microwave might be set to 65s, and it will run 20s and stop with all circuit dead. Wait a few
    seconds and the power returns, and I run the microwave the remaining 45s. Sometimes it does
    not happen, somtimes it happens at different intervals.
  7. When this first started, I was confident that the backstab outlet was loosing contact due to a
    heating/expansion, cooling/contraction scenario. So, I replaced the microware/toaster outlet
    with a terminal connection unit. Proud of my handywork, I tested the microwave to learn that
    I still have the same problem.
  8. So, thinking it’s the other outlet, I also replaced that outlet. Again, no change. I began to think
    that the outlets I’d supplied were cheap marginal units, I replaced them again with outlets that
    appeared of better construction. Again, no change.
  9. Exhausted, Frustrated, and dejected by my handtman skills, I scheduled an electrician visit. While
    awaiting that visit, I tinkered around with the microwave testing until I could no longer get the AC
    power to return. I left it alone for the electrician.
  10. So he comes in, probes the outlet, and asks me what’s wrong with it? WHAT!!!, it had been
    sitting for several hours because I couldn’t get power and I gave up. Then, he walks in and it’s
    hot. He checks the breaker and some other stuff, and can find nothing wrong. He even pulls the
    outlets and blesses the job I’d done with the replacement.
  11. So, as of this writing, I have a written log of failures. And, through testing, I’ve had a dead
    circuit for the past 8 hours or so. The electrician told me to call again once I could reproduce
    the problem, and he’s waive his trip charge. I’m just hoping that the circuit remain dead.
  12. Of course, I’m no electrician, but beyond the heat/expansion, cool/contraction connection fault
    I described earlier, I can not think of a way that a circuit can go cold, and return to hot.
    Neither could the electrician. He could not diagnose the problem on the circuit if I couldn’t make
    it fail. And he had no other suggestions.

See, I warned you it was complex. But everyone had excellent questions, I thought I needed to just
tell the whole story.

Thanks - gmak.

9

Go to the hardware store and get one of those cheap electrical testers that plug into the outlet and tell you if it is wired correctly (looks like a plug and has 3 LEDs generally 1 red and 2 yellow. If wired correctly the 2 yellow light up.) One of these is about $5
When the circuit is dead plug this sucker into every outlet you can find. Go to other rooms and test those also. Do not assume, test. Some flake in the past might have done something really strange with the wiring.
Once you know exactly which outlets are the ones on that circuit you can then test to see if you are losing the hot or the neutral (the tester will tell you that). This will give you information for the electrican.
One last thought. Does the microwave have an internal circuit breaker? Have you verified power loss with something else?

10

Is there anything else on the circuit? Lights, perhaps?

The first thing I’d do is open the circuit breaker panel and check the hot and neutral terminations for this circuit.

The (black) hot wire on this circuit terminates into one of the circuit breakers in the panel, obviously. Turn off this circuit breaker, and then remove the hot wire from the breaker by loosening the terminal with a screwdriver. Examine the copper portion of the wire for any evidence of arcing or overheating; if you see evidence of this, replace the breaker and then cut, re-strip, and reinstall the wire.

The (white) neutral wire on this circuit terminates into one of the holes in the neutral/ground busbar in the panel. You need to figure out which wire it is. Once you do this, turn off the circuit breaker, and then remove the neutral wire from the busbar by loosening the screw with a screwdriver. Examine the copper portion of the wire for any evidence of arcing or overheating; if you see evidence of this, cut, re-strip, and reinstall the wire into a different hole in the busbar.

11

While not a likely contributor to the intermittent fault, the 15A receptacles on a 20A circuit isn’t right and I’m surprised the electrician didn’t spot it. The circuit should be protected according to the lowest capacity wire or device.

12

15A receptacles on a 20A circuit is allowed under code in the US as long as it is not a single simplex outlet on the circuit. The device itself is rated for 20A pass through. In Canada this is not the case and you need 20A T shaped receptacles.

13

Most outlets are 15 amp. Just walked through my house and all are 15 amp. The wire needs to be 12 or larger on a 20 amp circuit.

14

Only two outlets on one breaker. Is your house small or do you have a large panel in your home?

If you had stab on outlets and the wires were daisy chained through the outlet they are going to fail.

How are you testing for the outlets being dead?

15

Rick…

Yes, I’ve seen those testers, that’s a good idea.
I don’t know about the microwave’s circuitry, but the toaster plugged into
the same outlet will not work. And, the seconds outlet about 6 feet away is
also cold.
Crafter…

I think the circuit is comprised only of these two outlets. There is a range
top, vent-a-hood, and a double oven on this kitchen wall. But they are not
affected. I know that when the double oven was installed a few years back,
it was segregated on a unique circuit to meet code. I’m sure it’s 220
anyway.

I understand your breaker box diagnosis instructions, but this is a little
deeper than I plan to venture. I would have assumed that the electrician
would’ve done this, or will do it when he returns. I will say that the
breaker box is one of those FPE warning units(I think).
gotpasswords…

Yes, a 20A outlet on a 20A circuit would seem appropriate to me. But, I just
replaced the outlet with a 15A unit because that’s what I found originally
installed. The original 15A unit had been working without issue since my
1986 purchase, on the 1974 consrtruction.
Fins…

Yes, I guess so. Whatever you say.
All…

I think I’m gonna’ get the tester, as recommended by Rick, and do as much
diagnosis as I’m comfortable with. I’ll identify/verify all the outlets on
the circuit. And see what the tester lights indicate when probed. As I
mentioned earlier, right now, the outlets are cold. Wait, let me verify
that… Yes, the outlets are cold, the breaker is not visably popped, and
it’s been in this state for at least 8 hours. Neither outlet contains any
plugs currently. I’ll ask if the tester will register on an outlet in this
state. Or, must known power be present.

Then, based on those discoveries, I think I’ll reschedule the electrician to
check the box as I mentioned to Crafter. Personally, I’m more worried that
the circuit is interrupted somewhere between the box and the outlet(s), like
from a varmint or other damage.

I’ll post my facts as the saga progresses. Hopefully, I’ll gain a final
disposition which I will relay should anyone else have anything similar. I
found this site via a structured search that took me to another similar
question here.

Thanks,

gmak

16

I think they’re all probably 15A

17

I think they’re all 15A.

18

There’s either an appliance(s) plugged, or a testlamp.

19

15A receptacles can be used on a 20A circuit and are 20A pass through.

try that circuit with a different breaker.

could be some chance of a break in the cable between breaker and first receptacle that gives intermediate open circuit.

20

Internally, there’s no difference between your typical 15 amp and 20 amp outlet. The only difference is the extra slot. Inside, the conductors are all the same size (usually). This is why the NEC allows you to put 15 amp outlets on 20 amp circuits.

Even though there’s no internal difference, if you use a 20 amp outlet, the NEC assumes you intend to use its extra current carrying capacity, which is why 20 amp outlets have to be installed on their own dedicated circuit.

If it were my house, I would get rid of all of those damned things. I personally wish the NEC didn’t allow them. I have no reason to assume that it will have any bearing at all on your current problem, but I just do not like backstab connectors at all. I think they cause too many problems in the long run. (just my 2 cents)

Yep. I don’t think this is actually required by code, but it is commonly done as good practice in almost all new construction. It’s pretty common in older homes for the breaker to get tripped if the microwave happens to be on while the fridge kicks on.

It’s definitely an intermittent connection somewhere. It could be the breaker itself, or it could be in any of the wiring or connections anywhere along the hot or the neutral side for the entire affected circuit.

Are you handy with a voltmeter? Do you know exactly how the electrician was testing the circuits? Was he just looking for voltage or did he actually measure the value? If you know how to use a voltmeter check the actual voltage level at the breaker box, at the affected outlets, and again in both places while the microwave is running (don’t run the microwave empty - put a cup of water in there if nothing else). For this type of problem, a voltmeter will often show a problem where a simple tester won’t.

What type of breaker is it?