Implementations disclosed herein generally relate to systems and methods of protecting a substrate support in a process chamber from cleaning fluid during a cleaning process. The method of cleaning the process chamber includes positioning in the process chamber a cover substrate above a substrate support and a process kit that separates a purge volume from a process volume. The method of cleaning includes flowing a purge gas in the purge volume to protect the substrate support and flowing a cleaning fluid to a process volume above the cover substrate, flowing the cleaning fluid in the process volume to an outer flow path, and to an exhaust outlet in the chamber body. The purge volume is maintained at a positive pressure with respect to the process volume to block the cleaning fluid from the purge volume.