You posted question under Steamist:
Sample Steamist manual says:
"Error messages E4, E5 and E6 indicate a communication problem with the steam generator. If this error occurs, check both ends of the control cable for clean, dry and secure connections.
Dirty contacts can be cleaned with alcohol and a cotton swab or a toothbrush. This can also happen if the control is not sealed and the cable connections get wet."
Error codes change as technology changes, and sample manual may not include your model:
Contact company directly for product manual and troubleshoot help from manufacturer
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