E1 indicates that the Haier washer-dryer did not drain within the time expected by its control system. This interpretation does not correspond to Err1, which indicates a door check.
The Haier Appliances table documents E1 for draining. The table sets four minutes for that detection in the washer-dryers described; it is not a common limit for all Haier models.
Check whether the drainage is none or partial
Look for visible water and the hose's exterior route. A crushed hose or a clogged household drain should be checked before buying parts. If the water drains slowly, note it: some of the contents disappearing does not prove that draining is working correctly.
Check the user access to the filter and its controlled draining. Do not open the filter with hot water or with the washer-dryer running. If there is no accessible procedure or you cannot collect the water, request assistance.
If E1 persists after the permitted checks, the drainage circuit needs diagnosis. A humming sound does not confirm that the pump is working properly and does not justify continuing to repeat cycles.
Keep E1 without adding Err when reporting the issue; that distinction keeps the review in the correct system.