Is there a risk of overheating with a 20 amp breaker, 12 gauge wire, and 14 gauge wire feeding two ceiling lamps with LED bulbs?
Asked by Idavide da Cruz 
3 months ago
Last Updated: August 19, 2024
I’m wondering about the practical implications of this setup: using a 20 amp breaker with 12 gauge wire, with the first break at a receptacle. This receptacle then powers another receptacle with 12 gauge wire, as well as a light switch with 14 gauge wire. The light switch controls two ceiling-mounted single bulb lamps with 40 watt equivalent LED bulbs each.
Just to clarify, the first receptacle has two lines coming out of it – one goes to the switch and the other goes to the second receptacle. I think this might not be up to code, but I also think that the draw from the light bulbs isn’t enough to cause the 14 gauge wire to overheat.
You can connect 6 outlets on a 20 amp #12 wire up to around 60 ft from the panel.
Hey, when I finished my basement in NJ back in 2020, there weren’t any restrictions on the number of outlets per circuit. I think it’s still the same, but I was pretty cautious. I ended up installing four 20amp circuits – one for lighting, one for lighting and outlets, and the other two just for outlets.
While it may not necessarily cause your house to burn down, it’s best to adhere to code standards to avoid rejection by an inspector.
Absolutely!
Have you considered changing it to a 15a breaker? This way you’ll have a part of the run that is larger than needed, instead of smaller.
I considered removing it as well, but I kept it there due to the risk of power equipment being connected.
You have to be careful because using wires that are undersized can create a fire hazard. It’s important to ensure the wires are rated higher than the breaker.
Opt for LEDs over those outdated 20th-century sockets. This way, you’ll consume fewer amps, which complies with the code in this area.
No good! It needs to be 12awg throughout.
No real impact. Remember, a lot of fixtures use #16 or #18 wire for the final stretch of wiring. Disregarding code because you asked.
Consider reducing the breaker to 15A to avoid a potential code violation.
You might want to consider changing the breaker to 15 amps as it is still a fire hazard.
Do many people really use 18 gauge extension cords with 20 amp plugs? I personally don’t see it becoming an issue, but adding a few feet of wire as a 20 amp rated plug AND SWITCH could address your concern.
Just swap out the feeder line (14g) for a 12g, as most people suggest that your 14g determines the breaker (according to code). Your point about the load on two lights is valid.
It’s not possible to downgrade a wire from 14/2 to 12/2, but upgrading along the line is acceptable. You should be fine with this approach.
If you switch the 14 gauge wire with a 12 gauge wire or install a 15 amp breaker, you’ll find that the difference between a 20 amp and 15 amp breaker is only noticeable when reaching the maximum capacity. This is the safest solution for your situation.
Just to clarify, having two properly functioning lights should not cause any issues in your specific situation. It’s when wires get overloaded due to malfunctioning components that fires can occur. The breaker is designed to trip before the wire becomes too overloaded and catches fire, but using the wrong size wire can lead to burning before the breaker trips. Swapping out the breaker for a 15 amp one should be sufficient for typical household outlet usage.
“Code” is basically the bare minimum requirement. It’s like getting a “D-” grade – it’s the least you should aim for. If something doesn’t meet code, chances are it won’t be as durable or safe in the long run.
Flaherty Remember, the code represents the legal minimum requirements. It’s designed with a significant safety margin in mind.
I think the pass/fail aspect is there for a reason, but we shouldn’t automatically assume it’s the ideal solution. Following the code minimum is important, as it sets the baseline for what needs to be done.
Let’s switch out that 14 gauge wire for a 12 gauge wire to match the 20Amp circuit.
About 30-40 years ago, this was a common practice in certain areas. You would typically have a 20 amp breaker with 12 gauge wire supplying a series of outlets in a room. Then, a 14 gauge wire would run from the last outlet to the light fixture. It was a convenient method that some electricians from different regions used, leading me to believe it may have been up to code back then.
I’m not sure what my tenant plugged in, but the 14 gauge wire was fused to the back of the outlet. Just because it’s allowed in a 70+ year old house doesn’t mean it’s safe. Running 12 gauge wire all the way is better than risking your house.
Sure, it should ‘function’ fine unless there’s an issue with the 14 gauge line. If there’s a problem with the 14 gauge line, there’s a risk of fire because the wire isn’t rated for 20A. It could melt and the breaker might not trip. The chances are low, but I wouldn’t take the risk for something so simple that could be easily fixed.
Just switch out the breaker for a 15 amp and you’re good to go…
When I was a child, our house caught fire because the previous owners used 14 gauge wire on 20 amp circuits!!! Almost lost my dog, too!!!
Is there any way that the 14 gauge wire could exceed 15 amps? Unless there is a serious issue inside the outlet box, I can’t see how that would happen, especially with LED bulbs. Personally, I wouldn’t worry at all about this situation and don’t see any danger. It’s similar to plugging in a light fixture with 2 LED bulbs into one of the outlets. I suppose it could potentially short out if the 14 gauge wire were somehow damaged and exposed to 20 amps (although highly unlikely), so if you want complete peace of mind, consider replacing the 14 gauge romex with 12 gauge romex. Since it’s all exposed (which is why it should have been done with metallic flex cable initially) and would only take about an hour to correct. Given that this seems to be a basement area where power tools may be used, I would opt to upgrade the wire before downgrading the breaker, and also install 20 amp receptacles if desired.
Always keep the wire gauge consistent ..