My son bought a house in Orlando, FL built in 1987. I have been going through checking everything electrically and correcting issues both large and small. This forum has been a blessing in getting answers. Safety is my biggest concern.

One big issue remains. I found one receptacle where the tester showed reversed polarity. No biggie, I thought. Probably the wires were switched. I was surprised to find out they are NOT.

This receptacle seems to be at the end of the run with no other splices in the box so something upstream must be amiss although I could not find anything peculiar in other boxes on the circuit. I noted that the cable in the suspect box appeared "different" in the sense there was no paint overspray on the wires like every other box has, almost like it was newer or changed for some reason?

I am ready to call a professional but am wondering just how he would go about this? Am I expecting too much? Would this be a nightmare for someone in the trade to figure out? Thanks.

 

A plug in tester is not always correct. First you need to use a multimeter to see if you really have a problem. If you don't have a multimeter by a cheap analog multimeter. (Digitals can be problematic on AC in some instances.)

 

I should have mentioned, I did do some checking with the multi-meter. As I understand it, checking the white wire side to ground hole should read zero. I got 120. And reading across the two slots was odd like about 24. This is why I am ready to call a pro. This makes me uneasy, especially not knowing the house's history.

 

What do you get narrow slot to ground?

 

Allow me to re-confirm tomorrow before I put out false information, Thank you.

 

There may be an open neutral upstream.

 

OK, went back for definitive multi-meter readings. Measuring across from large slot (white wire) to ground---119. From small slot (black wire) to ground---4. Across the two slots---21. I did this three times with similar results.

 

Check and make sure the correct color wires are on the correct terminals.

You definitely have a connection problem. The best way to locate where the problem is... is to shut that circuit off and identify everything that's on it. Once everything is dead and you've located everything that is dead.... start checking at the nearest dead junction boxes.

It sounds like a device was added in later and may not have been wired correctly.

 

It just seems appropriate to tell the end of the story once as it has become known since members offer suggestions to help. What did it tuirn out to be?

I had an appointment for a very experienced "electrical guru" to come try and diagnose the issue this past Friday. Murphy's Law: he got the flu. BUT, I found the issue by accident today. My son wanted a light installed over a dining room table. I peeled back the blacket insulation and exactly one foot from where I had planned to put the light I found the mess shown in the picture below.

Evidently a light of some kind had been there previously, but the hole was stuccoed over. Someone connected the black wire from one cable to the white of the other and didn't connect anything else. I installed a box with a cover and corrected it properly. Problem solved. I am thrilled after being vexed by this for weeks. Thanks for the suggestions on the forum.

 

Excellent example of the fubars hiding in many homes. Thanks for posting. It may help someone else.