My air condition says it need a 15 amp break but my breaker is 20 amp but it keeps throwing the break why is that

Hello

Is this a window A/C? Is it on a dedicated line just for A/C? Is A/C 110v or 220v?

With this info may be able to help u.

If a 110v line plug a light into it and see if breaker trips when light is turned on. If it does, u have wired the plug wrong.

Chuck

If the a/c is rated at 15amps, I would wager that it is 115/120 V. If the circuit breaker instantly snaps when you plug it in or turn it on, the a/c probably has a dead short in it... more than likely a bad compressor or starter capacitor.

Does this happen when you turn the a/c on or when you just plug it in?