pressure switch faulty or the pressure chamber is BLOCKED with powder residue ,even may have rubbed a hole through the plastic pipe
remove the lid locate the pressure switch ( has wires and a small plastic pipe attached) pull off the pipe and blow down if you go RED than the pipe chamber is blocked if you can blow it free this MAY cure the overfill problem
as machine fills with water the air trapped above the pressure chamber INCREASES causing the switch to turn off the water supply.
wirecutterman
July 2008