I have 16 lights and receptacles that are 14 ga copper wiring except two split receptacles that are intermingled with 12 gauge wire that was placed on a 20 amp breaker? What is the best way to do this correctly?

Should I add a new 15 amp circuit breaker and conduit that should be added to correctly wired for the 16 outlet:lights and then change the two 12 intermingled (14 and 12 gauge wire receptacles;0) to 12 gauge and use the existing 20 amp breaker which feeds directly to that 20 amp breaker?

  • 1
    Not quite sure what you're asking / describing. You have a single circuit with 16 lights and receptacles on it? It's all #14 wire, except for some portion which is #12, and its on a 20 A breaker? You want to add a new breaker, or replace the existing 20 A breaker? Can you clarify your question with additional details, maybe a little schematic or photos showing the wiring?
    – mmathis
    Mar 10, 2017 at 16:54

1 Answer 1


This is dangerous and could start a fire!

If I understand you correctly, you have a circuit which contains a mixture of #12 and #14 wire, that is protected with a 20 A breaker. If so, that breaker needs to be changed immediately to a 15 A breaker. #14 wire is only rated for a 15 A breaker, and having any #14 wire at any point in the circuit, no matter where and no matter how little wire there actually is, means the circuit must be protected by a 15 A breaker. You must use the smallest current rating of any of the wires / devices in the circuit to determine the proper breaker size.

The breaker should be turned off and the circuit not used until it is replaced.

  • It been like that for at least 7 years. Thank u will try to fix it immediately Mar 11, 2017 at 5:32
  • Temporary can I just switched the breaker to 15 amp s even though their is a 12 gauge wire connected to the breaker until I remedy this problem. Been like this for 7 years Mar 11, 2017 at 5:35
  • This was done when the electrician put in a new panel box and changed a couple of the receptacles. I wouldn't have found the problem if I erent replacing all receptacles Mar 11, 2017 at 5:45
  • @larrypinsky yes, replacing the breaker with a 15 A breaker is the easiest solution. The other one is to replace all the #14 wire with #12, but that probably involves fishing wire through walls.
    – mmathis
    Mar 11, 2017 at 5:46
  • Great idea--should had done that years. Ago. But I can start on some gradually. Mar 13, 2017 at 4:22

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