Arrived onsite for no cooling. Turned on ac system. Heard the blower motor come on. Looked at the attic air handler and check emergency pan for condensate water leaks. Did not see any. Went to the outside ac condenser. It was not on. Checked electrical. Cleared dirt and cobwebs from components. Confirmed no voltage to the outdoor unit. Checked circuit breaker. It was tripped. Reset breaker. Labeled breaker and showed homeowner.