Passway™ Troubleshooting Guide

Most grease trap issues can be diagnosed quickly by checking fundamentals: correct installation position, stable hydraulic fall, a chamber that has been commissioned properly, and a servicing interval that matches the site’s real loading. When those basics are right, Passway grease traps are typically very predictable in operation.

Odours
If you notice unpleasant smells, start by confirming the lid is seated correctly and the sealing surfaces are clean. Odours are often linked to overdue cleaning, trapped solids, or a lid that has not been latched evenly. If the site has had stormwater or surface water exposure, also confirm the unit location has not been flooded—unwanted inflow can disturb normal separation behaviour and lead to nuisance smells.

Slow drains or backups
Slow drainage is often a sign that the trap is overdue for service or that upstream solids are entering the system faster than expected. Confirm the basket is installed correctly and not obstructed, and confirm the downstream drain has the correct fall and is not restricted. If a site has recently increased occupancy or kitchen activity, you may simply be seeing a higher load than the current servicing interval can handle.

Cleaning required more often than expected
If the trap is filling rapidly with grease and solids, look first at user habits and kitchen practices. Excess grease introduction (for example, tipping oils into the sink) can overwhelm any grease trap. Reset expectations around scraping and oil disposal, then reassess the cleaning interval. In higher-load sites, more frequent routine servicing is normal—and far cheaper than plumbing failures.

Water level behaviour seems unusual
If water levels appear inconsistent, confirm the unit was commissioned correctly and that the outlet line is free-draining with appropriate fall. Poor fall or partial restrictions can create “lazy” flow-through and reduce separation efficiency. A quick inspection and line check usually reveals the cause.

Leaks around the lid or body
Leaks are typically linked to sealing surfaces, latch seating, or movement in the surrounding ground finish. Confirm the unit is stable and level, clean sealing faces, and re-seat the cover evenly. If the unit is installed in a paved area, make sure the finish level still allows proper cover removal and re-fitting without distortion.

If you don’t find what you need here, refer to the supplied manual for your specific model and contact WCTNZ® with the details of your installation and symptoms. Photos of the lid seating, surrounding ground level, and inlet/outlet connections help resolve issues much faster.

Warranty note: Passway™ grease traps are supplied with a Limited Warranty. Coverage is conditional on warranty registration and proof of purchase being returned within the required timeframe, and on installation being completed in compliance with the instructions and applicable standards by a licensed plumber. If installed by anyone other than a trade professional, warranty cover is limited to 1 year. Remedies are limited to refund, repair, or replacement and exclude labour/installation costs; full exclusions and conditions apply.

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