Operational maintenance of air-conditioning installations

An assembled pump compressor arrangement of an air-conditioning system having a housing enclosing an impeller with a thrust collar positioned thereon. The arrangement includes a tool for applying torque to the impeller having an outer cylindrical element and a plurality of arcuate sections. The arrangement further includes a releasable clamp for interconnecting the arcuate sections and the outer cylindrical element with the impeller clamped between the outer cylindrical element and the arcuate sections. A torque bar is provided which extends through the outer cylindrical element in a spaced relation to the impeller through which the torque is applied to effect disassembly of the high-speed thrust collar and removal of the impeller from the housing of the air-conditioning system.