Each module comes with a Shell example. It provides a command-line REPL-type interface. It also demonstrates the vastly improved error checking and handling in our new modules. If there is a problem that is possible to be detected in the hardware or firmware, it will bubble up to an error code.
This is great because it will identify issues and tell you about them without you having to wonder why it is just silently failing or giving you some odd result.
You can find the Shell example in the Examples menu in the Arduino IDE, or you can run it on you Raspberry Pi aftering install the library (for EC, python3 -m uFire_Mod_EC.shell, pH python3 -m uFire_Mod_pH.shell, ORP python3 -m uFire_Mod_ORP.shell).
So if things aren't working as expected, try running the Shell example. It might give you some insight into the problem.