error Worcester

Error Code H

Fault indicator symbol — appears on display when a fault has occurred in the appliance.

? What Causes This

Various appliance faults; specific cause indicated by accompanying fault code number.

Note the fault code displayed (e.g., 214).
If the fault causes shutdown, press the up and down arrows simultaneously until symbols H and ! are no longer displayed.
If fault persists, contact Worcester, Bosch Group or a qualified service engineer with the fault code and appliance details.

Source: page 14 of the official manual

From the manual

This error code appears in: