Is it safe to use both 14-2 and 12-2 wires on a 15A circuit?

Answer 1

(LIFE SAFETY WARNING! [disclaimer]

Electricity is dangerous!

You can be injured or killed!

Improper installations can cause fire, injury and death!

Should you be doing this yourself?)

This is one of those questions - if you know this little, you shouldn't be doing what you are planning...

No disrespect intended, but this is SO basic that it suggests you have not studied the subject at all!

There are many good reference books and course books to study from.

According to the NEC, you can utilize any conductor with suitable insulation for any application for which the conductor is rated for the use.

The limitation to the gauge size of conductor is that it be AT LEAST as large as that called for in the conductor tables, based on current, ambient temperature and conductor grouping!

ALWAYS CHECK WITH YOUR LOCAL WIRING SAFETY OFFICE BEFORE YOU ATTEMPT TO CHANGE ANYTHING ON POWER MAINS OUTLETS

IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

If you do this work yourself, always turn off the power

at the breaker box/fuse panel BEFORE you attempt to do any work

AND

always use an electricians test meter having metal-tipped probes

(not a simple proximity voltage indicator)

to insure the circuit is, in fact, de-energized.

Answer 2

No, it is not safe to mix 14-2 and 12-2 wires on the same 15A circuit. The circuit should be consistent in wire gauge to prevent overheating and potential fire hazards. It is recommended to use either all 14-2 or all 12-2 wires for a 15A circuit.

Answer 3

Safe? Yes. The only probles are:
1. it's a waste of 12 ga wire.
2. The next person to come along may see the 12 ga wire and think it's okay to put in a 20 Amp breaker.

Answer 4

Yes. It is a larger gauge than you need, but it is fine.