Does the entire association pay for limited common area maintenance?

I live in a condo building with three residential units and one commercial unit. The commercial unit does not have access to the residential stairwells, but the three residential units do. The residential units pay more assessment dues than the commercial unit per month, which I assumed was because of the stairwells.

I am the president of the association and I live in a residential unit. The treasurer owns the commercial unit. He recently told me that he does not want to contribute to paying for the cleaning of the residential hallways anymore, and the residential units must pay for this out of our own pockets, on top of our current assessment dues. I also asked him about purchasing smoke alarms for the residential hallways, and he said that was a 'limited common element expense' and we'd