When the evaporator unit is positioned 3 m (or more) above the condenser unit, we must install a siphon at the outlet of the evaporator unit, in the suction line, avoiding the return of liquid to the compressor. When the condensing unit is installed above the evaporator unit, siphons must be installed every 3 meters in the steam (suction) line to allow the oil to return to the compressor.
