I had an air scrubber in an isolated room to which I routed CO2 collected around the base, and was switching the scrubber on when there was enough pressure in the room to save power.
Later I made a better recycling room elsewhere so I deconstructed the room and the scrubber. A bottle of CO2 was left on the floor. I selected it and clicked the Empty Building button. Within a short time, my whole base was literally flooded with high pressure CO2, exceeding 4 kg of CO2 per tile even when half of the base was already full.
When checking the new CO2 recycling plant, I found out its air scrubbers already made over 150 kg reserve of CO2 each.
Air Scrubber should not hoard CO2 beyond all limits, when the storage exceeds some reasonable value such as 1 kg it should stop absorbing CO2 from environment and just process the reserve until it is below the limit again.
Load attached save, unpause, watch action of air scrubbers. Also check out the flooded base (around the printing pod).