i have no idea why they dont work, i just bought this house and i know nothing of the pools history. i just found two more jets in the stair case (left and right) on the bottom stair, and they dont work either, all the ones that dont work were all caped except the one that does work. their are no valves or anything of that nature for them, so i assume they were disconnected underground, maybe there was some kind of repair and they didnt reconnect them i really just dont know!