There is a bug with Configurable Valves pump in a Sandbox environment. I also made a bug report on the Configurable Valves mod: https://mods.factorio.com/mod/configurable-valves/discussion/6a328a7c6311a4093fa9a78a. When a pump changes configuration, for example from regular mode to overflow mode, the pump is instantly deleted from the Sandbox environment where I am designing my blueprints.
