Overloaded MWBC and now switches and receptacles have low voltage

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Old 11-17-19, 06:03 PM
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Overloaded MWBC and now switches and receptacles have low voltage

So I had a space heater on an outlet in a bedroom. At some point everything in 2/3 of the house.. lights, heater, tv.. started pulsing on and off.

I unplugged everything going to those outlets and reset the breaker (which wasn't tripped). At this point I turned the lights on and they strobed. If I plugged a night light into an outlet, it would power it but the lights would go out. So I'm getting very little power but none of the outlets or switches on that circuit are dead.

I opened up the panel and found the 2 15amp breakers (black wire on one, red on the other) and 2 20 amp breakers (black and red as well). The neutral isn't damaged at the panel and the wires going to the outlet used by the space heater aren't damaged (I twisted them together to eliminate the receptacle, in case it was bad)

So is this a situation where I should replace those 4 breakers or do I need to replace all the switches and receptacles, one by one? Only one 15 amp breaker actually kills power to the rooms. The other 3 have no affect whether switched on or off.
 
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Old 11-17-19, 09:38 PM
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Measure the voltage on the breakers in question when the lights are not working. If it is constant then the problem is elsewhere.
 
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Old 11-17-19, 11:50 PM
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Welcome to the forums.

If I plugged a night light into an outlet, it would power it but the lights would go out.
It is not a breaker issue.
It does appear to be an open neutral based on what the lights are doing.
You're going to have to pull out and check the wiring on all the receptacles on that circuit. If you see push-in back stabbed connections..... they need to be changed to the screw terminals.

VERY IMPORTANT..... you've confirmed a MWBC...... turn off both breakers for those two circuits while troubleshooting.
 
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