Pressure assist toilets suck.... we installed a few of them in a doctors office
and the expansion tanks wore out in about a year from too much action all day long..
They about flooded out the place and I was able to just buy the whole exact tank and
change everything out instead of fooling with the sloan parts.....
their have been a lot of recalls on them in the past too so I stay away from them
good luck with it , and keep a spare tank on hand just in case...