GreyFlow™ Installation Overview

What to expect

GreyFlow™ installs are tidy when you follow the staged sequence: place/trim the pit, plumb inlet/overflow, fit filters and pump, then connect the sub-surface irrigation zone(s) below mulch. Finalise electrics and commission with a flush before bringing the irrigation online. A licensed plumber must perform PVC connections and sign-off for consented works. 

PS System (new homes on slab)

The PS pathway splits into Builder’s Kit (pre-lay carcass with in/out/overflow penetrations) and a Finishing Kit (manual or auto filtration + pump/controller) at fit-off. This sequencing lowers construction cost and avoids re-work after paving/landscaping. 

PRO System (retrofit / general use)

The PRO pit is depth-adjustable (cut to height) for easy alignment with existing drains. After trimming the riser, install filters, set the submersible pump, run conduit/cables to the cabinet (auto) or power point (manual), and flush the system before coupling to dripline. 

Irrigation zones

Use GreyFlow™-approved dripline and manifolds; keep run lengths and station splits within spec (e.g., use the rotor/indexer for multi-station distribution). Signage for “greywater in use” is required; keep discharge below mulch/soil. 

NZ-relevant notes

Discharge must be sub-surface; isolate kitchen flows; provide a dedicated power supply; and shut systems down during heavy rain or runoff conditions where required by council rules. 

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