Horizontal type-reciprocating compressors, cylinders of contrary direction simple or double effect and with crosspieces, every line drives two mount support decaladas 180 °. This type of compressor is perfectly balanced since: - Both pistons of each line move in invertid direction. The primary and secondary compound forces are annulled and all the possibilities of vibrations and any type of shakes are suppressed on the foundations. - The resultant efforts on every mount support are equal and opposite and create an axial couple without any reaction on the cushions of the housing unit. Every stage of compression is refrigerated in water, as much in the cylinders as in the bottoms, like in the interchangers.