For the last month or 2, I've noticed that the pressure sensor seems to be failing (getting rather erratic and known false values). I haven't thoroughly tested all components (mainly wiring, solder joints, etc.), but attempts to clean/fix the sensor itself seem to result in 'changes' to the values but still ultimately false values (i.e. leaving it open to atmosphere can give wildly different values).

When I originally included the pressure sensor, it was because I wasn't weighing the CO2 tank and I wanted some kind of indicator of it's level. If I were to redo the project, I wouldn't even include the pressure sensor due to it's cost, it's limited value (I can only read the pressure downstream of the regulator, as opposed to the tank pressure) and now it's added failure mode.

If I get it working again, I'll post an update with hopefully how I fixed it.