My personal home has current on #6 to water pipe.

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I am going to take a couple of days and brush up on some stuff and do some more digging. I will update when I have some better info and have time to do some tests with the hair dryer again with current draw levels and voltage tests under load. Thanks to everyone so far with all the help.
 
Really reaching here, but do you have an AC unit with an inverter driven compressor? If so, perhaps a rectifier diode is blown so that it's only working as a half-wave rectifier. That would create a lot of second harmonic current and make the phase-to-phase voltage on the panel bus drop somewhat every other half-cycle. Then each 120V phase to neutral voltage would be "modulated" the same way, and maybe this is sufficient to cause the fan motors to overheat? I'm not sure why the TV would be getting hot. Maybe it has a switching supply that adapts to different line voltages and it's reacting badly to the waveform.
I realize that the impedance at the panel bus is going to be low, and so the effect I mentioned above is going to be limited but it may still be in play.
Also, I suspect that a blown rectifier could cause an inverter drive to shut down but maybe not in all cases.
 
Eamp said:
They are separate pieces of 14-2 romex that feed each circuit on different phases.

They are on same side of buss.

Siemens AFCI.
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The red highlights are ambiguous. Here, with the breakers turned on, take a voltage measurement from the "hot" LOAD terminal of one AFCI to the other AFCI "hot" LOAD terminal. I am suggesting the breakers be installed so that this voltage measurement is ZERO volts. If you get something in the vicinity of 240 volts, that is not what I am suggesting.

Having the Siemens AFCIs protecting the two branch circuits is a good thing, for the kinds of wiring problems their presence rules out.

I assume the two Siemens AFCI still test as operational (the only approved test is to use the TEST button on the breaker itself.) The single pole Siemens AFCI has a ground fault sensing component in it that would trip if the load side connected branch circuit neutral were in contact (somewhere along the protected wiring) with the equipment grounding conductor (EGC). Also, the Siemens AFCI also rules out a "leak" of current from the insulated path of the load side hot through the utilization equipment and back through the white wire, as the AFCI ground fault sensing component would (should) trip in the forty to sixty milliamp current range.
 
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190929-2330 EDT

Eamp:

You need to do some basic experiments so that you get a feel for how things work. These I will call bench tests.

Study up on ohms law first.

An experiment I suggest is with a 250 ft roll of #14 copper Romex, your hairdryer, or a 1500 W heater, a couple voltmeters that resolve 0.1 V at 120 V, and an ammeter.

Leave the Romex coiled.

Connect a duplex receptacle at one end where you plug in the resistive load. Provide enough exposed copper at the duplex to connect voltmeter test leads to the wires. Better to be directly on the wires from a well designed experiment perspective.

At the input end provide some exposed copper for voltmeter test lead connection. Insert an ammeter in series at the input end. Provide a switched 120 V 60 Hz AC source to the input end.

Now you can perform various experiments.

Current thru copper wire creates heat and an increase in resistance with heating. The heater likely uses nichrome wire and this has about a 10% increase in resistance as it heats from room temperature to its orange glow. Take quick readings or wait until a reasonably steady state condition exists.

Running such an experiment on a 250 ft roll I got the following results:

1. Fluke 27 loop resistance measurement with the far end shorted was about 1.2 to 1.3 ohms. Correlates with published information for 20 deg C.

2. Input voltage 118.2 V, load voltage 103.8 V, at an I of 12.1 A.

3. Calculated resistance (118.2-103.8)/12.1 = 14.4/12.1 = 1.19 ohms. A good correlation.

You can make other measurements in this test circuit, change wire length, and change the load.

.
 
synchro said:
Really reaching here, but do you have an AC unit with an inverter driven compressor? If so, perhaps a rectifier diode is blown so that it's only working as a half-wave rectifier. That would create a lot of second harmonic current and make the phase-to-phase voltage on the panel bus drop somewhat every other half-cycle. Then each 120V phase to neutral voltage would be "modulated" the same way, and maybe this is sufficient to cause the fan motors to overheat? I'm not sure why the TV would be getting hot. Maybe it has a switching supply that adapts to different line voltages and it's reacting badly to the waveform.
I realize that the impedance at the panel bus is going to be low, and so the effect I mentioned above is going to be limited but it may still be in play.
Also, I suspect that a blown rectifier could cause an inverter drive to shut down but maybe not in all cases.
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I like your way of thinking outside the box and coming up with the idea of second harmonics. I does make you think.

If something like this were to happen then how would the problem be isolated to just one bedroom circuit ? I'm not making a statement I'm asking a question.
 
growler said:
I like your way of thinking outside the box and coming up with the idea of second harmonics. I does make you think.

If something like this were to happen then how would the problem be isolated to just one bedroom circuit ? I'm not making a statement I'm asking a question.
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Very good question. Perhaps all of the ceiling fans in the house were on this particular circuit, and the other loads around the house were more tolerant of second harmonics? The OP would have to comment whether this was the case.
 
synchro said:
Very good question. Perhaps all of the ceiling fans in the house were on this particular circuit, and the other loads around the house were more tolerant of second harmonics? The OP would have to comment whether this was the case.
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Another question. If such a thing were to happen could this be confirmed or eliminated simply by turning off the breakers to the AC units and running the fans to see if the problem goes away.
 
growler said:
Another question. If such a thing were to happen could this be confirmed or eliminated simply by turning off the breakers to the AC units and running the fans to see if the problem goes away.
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Yes, that would definitely verify it one way or the other.
 
Eamp said:
Not MWBC, It started off about 6 months ago I walked into my sons room and it was so hot in there we were like what is going on. Walked past his wall mounted tv and I could feel the heat coming off of it. The housing on the tv was burning to the touch almost. We replaced tv assuming it was old and did not have problems after with new tv. Then 6 months later I hung a ceiling fan in his room. My sons room started to smell like burning and fan was burning hot also instantly within 2 minutes. I replaced the housing with the other fan I bought for my daughters room and same problem as the first. I chalked it up to cheap ceiling fans and returned them and bought more expensive ones. Installed new one in his room and same burning smell and heat. I installed the one in my daughters room which is on a separate circuit and hers will get burning smell after about 5 minutes but not as strong as my sons room. So far 4 fans all same burning heating issues. I have broke apart every joint, traced every wire up and down on both circuits over a week of free time. This was all before I discovered the current on GEC in basement. I believe I have checked the circuits to perfection at this point. There is no voltage drop at the fans or high current draw either. I am just looking for a new direction or explanation. Completely mind blown. I also fed his room from a separate circuit and phase with a piece of romex across the floor, same problem in both rooms. Only combining factor of the 2 rooms is they are the farthest circuits from my panel.
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I'm not sure that low voltage would even effect a fan motor unless it really lags down there. The idea of having a burning smell in a kids bed room does bother me as a safety concern. Are you sure it's the fan that's giving off the burned wiring smell and not the branch circuit wiring?

I think I would completely remove the fan and install a temp receptacle at that location. I would plug in vacuum cleaner (leaving the vacuum in the hall, they have long cords). On the other side of the duplex receptacle I would connect my volt meter to monitor power (voltage drop ) and let the vacuum run for 5-10 minutes ( a bad connection will often get worse as it heats up). If you get any burning smell with the vacuum running in the hall that should eliminate the fan.

Before doing anything make sure that fan motor turn really freely. I know you replaced the fan but I can't help thinking that the fan may be binding in some way as to slow it down or add load. I used to work on lots of motors and bad bearings cause motors to heat up more than anything. Sometimes problem are simple mechanical issues.

I have been reading about what would cause a TV to get hot and they state that even the brightness setting can change the operating temps. and the manufacturers state that a TV can operate at temps up to 125F which could seem hot to the touch.
 
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