Water Inc HOUSEPURE HP04 - Manual (Page 8)

15. Allow unit to run to drain for the duration of the cycle. 10 minutes.
Figure 4
With the valve In Service, manually initiate a backwash as the final installation
step. This backwash will:
a) Complete the final flushing and filtering of the water system.
b) Re-classify the media bed if the bed was disturbed during shipping.
c) Rinse any remaining residue from lines.