After about 5 min. my portable AC rated at 11.4 Amps trips the 15 Amp circuit breaker. I put a Kill-a-Watt meter on it and it was only drawing 0.33 Amps at time of the tripping. Only other running elec. object tied in to the breaker is 'smoke alarm'. Anyone have a fix or cause?

  • 2
    Does the breaker in question have a TEST button on it? Jun 20 '20 at 22:46
  • No test button. 1987 breaker.
    – baborn
    Jun 21 '20 at 0:09
  • What make and model is the breaker in question? Jun 21 '20 at 0:22
  • Bryant Bro looks like 80230-230
    – baborn
    Jun 21 '20 at 0:26
  • 3
    @manassehkatz-Moving2Codidact I suspect that his meter took the reading when the A/C's compressor was not running; fan only might pull that amount. He needs to take another reading, preferably with a known good clamp-on meter, when the unit is running in maximum cooling.
    – ehbowen
    Jun 21 '20 at 13:46

I agree with others .33a no way for even the smallest ac units. At 5 minutes I believe the circuit is being overloaded.

Most breakers for residential use are inverse time breakers. A 15 amp breaker loaded at 15.5 amps may not trip for a 1/2 hour push it to 16 amps and it will trip much quicker possibly 5 minutes.

I would check the load on that breaker with a clamp meter and would expect more than 15 amps. If the load is less than 15 the breaker is defective and needs to be replaced.

  • I want to thank everyone for your answers. I now believe that the problem is with the portable ac unit. I moved it to room #3 and it tripped that rooms breaker.
    – baborn
    Jun 22 '20 at 0:02

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.