my hotpoint wmf 540 is flashing H20 during a cycle what does it mean?????

it has 40min left on the baby care cycle and has H20 flashing up, this is a new machine and itd the 2nd time i have used it so i dont know what it wants. It has since completed the cycle i think....... we had problems when we fitted the water pipe to the machine could it be something to do with it?