A method of maintaining a synthetic gas (syngas) cooler for use within a gasifier system is provided. The method includes breaking at least a portion of a non-bonded joint and a seam weld on a quench ring assembly. At least a portion of the wear sub-assembly and a flow control sub-assembly is removed, and the wear sub-assembly is separated from the flow control sub-assembly. The method further includes removing the separation device that extends between the flow control sub-assembly and the wear sub-assembly. At least a portion of the wear sub-assembly is replaced by positioning the replacement portion of the wear sub-assembly over the flow control sub-assembly and coupling the replacement portion of the wear sub-assembly to the main structural member. The method provides a more efficient replacement of worn sub-assemblies, which decreases the time and costs associated with maintenance.