Method for producing vinyl chloride resin that prevents scaling

Scale forms inside piping that connects polymerization reactors for producing vinyl chloride resins. As scale growth increases, the interior of the piping becomes blocked, hindering the polymerization process. Reaction control is particularly difficult if the safety valve connection piping is blocked. Therefore, it is necessary to disassemble the connection piping and clean the interior thereof at regular intervals. Moreover, in such instances, there is a possibility that vinyl chloride monomer gas will escape from the system, which is undesirable. Provided is a method of production with which a countermeasure for preventing such events is performed. The connection piping in the upper portion of the polymerization reactor is consolidated, and nitrogen piping 21 is joined to the connection piping 20 and filled with an amount of nitrogen corresponding to the piping volume. It is thereby possible to cause vinyl chloride monomer gas, which is the substance that causes scale to form, to be forced back from the connection piping 20 into the polymerization reactor.