Earlier this week, I installed a 1ph 30a circuit for a new A/C install. I arrived first thing in the morning, got the wiring ran from the panel to the disconnect, turned the breaker on, checked for voltage at the disco, then turned the breaker off so the HVAC tech would have an unenergized disco to attach to. Later that afternoon, I got a call from the tech. He said the breaker won't stay on... acts like it's shorting out.
I said there must be an issue with the condenser as I had the circuit on up to the disco with no issues. He replied the breaker slammed open so hard it broke the handle off it.
I head out the next morning to check it out. On the 45- minute drive out there, I'm wondering what could be the problem. Did the tech rewire the line conductors in the disco? Did they send me the wrong specs and install a 3-ph unit (building does have 3-ph)? All sorts of scenarios went through my mind... 3-ph being top of the list.
Upon arrival, I check the nameplate. Yep..... Phase: 1. OK, so it's not a 3-ph unit. Or at least it's not marked as such. I pull the cover off to see how many poles are on the contactor. Just two. I take my idiot pen and push it in. Nothing.
I check the disco. It's off. I flip the pullout over and check for power. Nothing.
To the panel inside I go. Breaker is in the tripped position and the busted-off handle is sitting on top of the panel. "(*#(@ tech.... broke my breaker!" I go out to the truck and grab another one. Replace the broken breaker, turn on the new one and...... no Big Blue Zot.
I go back outside and push the contactor in. The unit fires up as it should. I then go back inside, find the stat, do a 'call for cool' setting and I hear the furnace turn on. Outside, I feel the heat being pumped out by the units' fan blades. All is well with the universe now, except for my time and gas for the trip.
I toss the busted breaker in my truck, tell the owner everything's good now and head off to a better-paying job. But on the way, it kept gnawing at me.... the tech said the breaker wouldn't stay on... acted like a short. And the breaker was left in the tripped position. So where did this short come from?!?!
With not much to do today, I pulled the busted breaker and a meter out of my war wagon and, on a hunch, did a continuity test on the breaker terminals.
That's right, boys and girls: A brand-spankin-new Square D QO230 breaker with an internal short.
I couldn't get (what's left of) the handle moved to close the contacts, but there's no short on the busbar connectors. I could only get it to move halfway between tripped and off a couple times... now it's permanently jammed into this position. So the short must be downstream of the contacts.
Good thing there wasn't a short in it when I pushed it into the panel.... that would have been a surprise!
So it's back to the supply house Monday for a credit with this one. I gotta admit it.... this is the first I've ever seen something like this. In any brand of breaker. New or used.
I said there must be an issue with the condenser as I had the circuit on up to the disco with no issues. He replied the breaker slammed open so hard it broke the handle off it.
I head out the next morning to check it out. On the 45- minute drive out there, I'm wondering what could be the problem. Did the tech rewire the line conductors in the disco? Did they send me the wrong specs and install a 3-ph unit (building does have 3-ph)? All sorts of scenarios went through my mind... 3-ph being top of the list.
Upon arrival, I check the nameplate. Yep..... Phase: 1. OK, so it's not a 3-ph unit. Or at least it's not marked as such. I pull the cover off to see how many poles are on the contactor. Just two. I take my idiot pen and push it in. Nothing.
I check the disco. It's off. I flip the pullout over and check for power. Nothing.
To the panel inside I go. Breaker is in the tripped position and the busted-off handle is sitting on top of the panel. "(*#(@ tech.... broke my breaker!" I go out to the truck and grab another one. Replace the broken breaker, turn on the new one and...... no Big Blue Zot.
I go back outside and push the contactor in. The unit fires up as it should. I then go back inside, find the stat, do a 'call for cool' setting and I hear the furnace turn on. Outside, I feel the heat being pumped out by the units' fan blades. All is well with the universe now, except for my time and gas for the trip.
I toss the busted breaker in my truck, tell the owner everything's good now and head off to a better-paying job. But on the way, it kept gnawing at me.... the tech said the breaker wouldn't stay on... acted like a short. And the breaker was left in the tripped position. So where did this short come from?!?!
With not much to do today, I pulled the busted breaker and a meter out of my war wagon and, on a hunch, did a continuity test on the breaker terminals.
That's right, boys and girls: A brand-spankin-new Square D QO230 breaker with an internal short.
I couldn't get (what's left of) the handle moved to close the contacts, but there's no short on the busbar connectors. I could only get it to move halfway between tripped and off a couple times... now it's permanently jammed into this position. So the short must be downstream of the contacts.
Good thing there wasn't a short in it when I pushed it into the panel.... that would have been a surprise!
So it's back to the supply house Monday for a credit with this one. I gotta admit it.... this is the first I've ever seen something like this. In any brand of breaker. New or used.
