Used the wrong gauge wire for a 20 amp circuit for 3 months until a panel swap tipped me off

I was wiring up a detached garage last spring and kept having a breaker trip on a 20 amp circuit. After 3 months of frustration and swapping outlets, the old timer I was helping on a panel swap asked why I had 14 gauge on a 20 amp breaker. Felt like a total idiot. Has anyone else missed something basic like that and only caught it way later?

3 comments

3 Comments

kellys786d ago

Oh man, that's exactly the kind of thing that keeps me up at night! I once ran speaker wire to a light fixture because I grabbed the wrong roll from my truck and didn't realize until the bulb literally caught fire. Three months on 14 gauge for a 20 amp circuit though, that's a classic oops. I bet that old timer got a good chuckle out of it while he was helping you. At least you caught it before anything melted or worse, right?

shanelee6d ago

My uncle did something close to that once but with thermostat wire on a 240v well pump. It worked for a solid two weeks before the insulation melted and the whole thing shorted out underground. Cost him way more to dig it up and replace it than if he'd just used the right wire from the start.

emery_black6d ago

Have you ever tried heat-shrink tubing in stages for a fix like that? I once had a similar situation with an old pool pump where I wrapped each connection individually and then a final outer layer, and it actually held up for three seasons without any issues. @shanelee your uncle's story is exactly why I always test with a cheap thermal camera now before burying anything.