A bidirectional air pump to selectively inflate or deflate an inflatable object has a housing, a pump assembly and a motor. The housing has a controller cover, a pump cover, and a motor cover. The pump assembly is mounted inside the housing and has a centrifugal pump, a binary supply/discharge valve assembly, a selectable check valve assembly and a valve controller. The motor is mounted inside the housing. The valve assembly and the motor cooperate to pump air into or draw air out of an air mattress or inflatable sofa.