The disclosure relates to a unitary heat pump air conditioner (Unitary HPAC) that includes a refrigerant loop having a condenser, a refrigerant expansion device, and an evaporator hydraulically connected in series. An electrically driven compressor is provided to circulate a two-phase refrigerant through the refrigerant loop to transfer heat from the evaporator to the condenser. The unitary HPAC also includes a cold side chiller configured to hydraulically connect to a cold side coolant loop and is in thermal communication with the evaporator. The unitary HPAC further includes a hot side chiller configured to hydraulically connect to a hot side coolant loop and is in thermal communication with the condenser. The refrigerant loop transfer heat from the cold side chiller to the hot side chiller, thereby cooling the cold side coolant loop and heating the hot side coolant loop. The components of the unitary HPAC are mounted on a common platform.