Systems and methods controlling the pressure differential between two sealed chambers connected by a gate valve in preparation for a gate valve opening event. Such systems and methods may adjust gas pressure in at least one of the chambers, if needed, until the pressure differential between the two chambers is at a predetermined pressure differential level. In some more specific examples, one chamber may constitute a substrate handling chamber, the other chamber may constitute a reaction chamber (e.g., for depositing one or more layers on a surface of a substrate), and the gate valve opening event may allow a substrate to be transferred from one chamber to the other (e.g., from the reaction chamber into the substrate handling chamber).