/ House A/C problem due to breaker #11
They have NOT discontinued making aluminum wire for branch circuits. They only discontinued it for 15-20 amp circuits. You can still use it on larger branch circuits. Todays alum wires are nothing like those of old.Test the start cap as tinhack said it is [possibly] bad but normally once they fail they are dead. My guess is the POS aluminum wire loosened up and caused a voltage drop requiring more amps to start the unit. I don't care what anyone says aluminum wire sucks! I personally have seen it burn down 2 homes so far. This is why they quite using it for branch circuits. Dicharge cap before testing it!!! If you have aluminum wire anywhere check the tightness of it every few years and more often where vibration is present. EG air conditioner. Or replace it with copper if that is a option. CJ
They have NOT discontinued making aluminum wire for branch circuits. They only discontinued it for 15-30 anp circuits. You can still use it on larger branch circuits. Todays alum wires are nothing like those of old.
we use it all the time. Also, all the power lines overhead are aluminum. It works great as long as its installed properly.
while you could run a 6/2 aluminum ser cable for a 30 amp ac unit ( as i recall thats the smallest aluminum romex style wire available )very few people do. Until the craziness in prices kicked in a year and a half back, 10/2 copper was relatively cheap And inline with the cost of 6/2 Aluminum. Last week i paid nearly $400 for a 250 foot roll of 10/2 romex. I expect to see more aluminum runs out there soon.
ps: i edited my last post. That was supposed to say 15&20 amp circuits…not 30. Fat fingers.
Personally i just think the connections were loose. Do you recall if the screws on old breaker were tight? Should need quite alot of pressure to loosen.
Instead of trying to point out posts with varying amounts of poor information, I'll just say imo everything the above quoted poster said in his posts is correct. I cringe at the sight of electric questions due to the number that always respond with poor information. I commend op for the common sense approach to fixing the problem then seeking affirmation. I believe his actions are those of one who understands more than the average but is and will remain a student reaching for perfection.Breakers do go bad. However usually when theres carbon buildup its due to wires not being tight on breaker. Aluminum wires are supposed to be torqued per spec on panel. Otherwise , if it were me, i would check tightness under every aluminum wire connection. Same contractor may not of tightened any of them.
loose wire causes arcing. Arcing creates carbon and heat. Heat trips breaker thermals.