We have a relatively new school building (<3yrs old) and we are continually having problems with our washfountains not working properly. The Units are Mf2903 & MF2904 Bradley units and they have pushbutton air valves which activate the faucets. The units either don't activate, have very short duration (1-2 secs), or the faucets do not shut off. We have been through multiple visits from the plumbing reps and they'll replace components but the problems recur. We've adjusted the valve timers, replaced all the valve components one piece at a time (diaphragms, magnet assemblies, armatures, valve springs, etc.) , but still have problems. Has anyone else experienced this? What would you do?