E8 is an excessive water level alarm in documented Haier combo units. Do not start another fill cycle to verify it, and do not interpret a reset as a repair.
The Haier Appliances chart refers this issue to service. The code identifies a level condition, not the part responsible.
Prioritize checking the water
If the level rises or a leak appears, stop using the machine and shut off the water supply if it is safe to access. Do not force the door open with water retained inside. If there is moisture near electrical power, avoid touching plugs or the housing and get help isolating the unit from a dry area.
Note whether the inlet continued after the program was stopped and whether the water actually came out of the appliance. Do not reproduce that behavior by turning the tap back on.
External observation helps service, but it does not allow you to separate the valve, sensor, and electronics. Do not blow into internal hoses or replace parts by elimination. Even if the level drops, request the proper inspection before using a machine that overfills again.
Provide the reference and the sequence of the incident so the technician can check both filling and level detection.