Troubleshooting — RO/NF Membranes (FilmTec™)
Keep your RO/NF system running at peak performance
When reverse osmosis (RO) or nanofiltration (NF) systems begin to underperform, the issue rarely points to a single failure. More often, performance changes appear as shifts in permeate flow, salt passage, or differential pressure.
These changes are often interconnected, and identifying the root cause requires a structured approach.
This troubleshooting hub is designed to help you quickly identify your issue and find the right next step—whether that’s cleaning, adjusting operating conditions, diagnosing the underlying cause, or determining when replacement is required.
Choose your symptom
Most RO/NF performance issues are driven by system conditions—not just the membrane—and symptoms are often connected. Start with the primary issue you’re seeing:
Low permeate flow
Reduced permeate flow may indicate fouling, scaling, or changes in operating conditions affecting membrane performance.
Increased salt passage (reduced rejection)
Higher salt passage can indicate membrane damage, leakage, or loss of separation performance.
High differential pressure
Increasing pressure drop across the membrane system is often caused by fouling, scaling, or flow restrictions.
Performance decline — should you clean or replace?
When performance drops, the key decision is whether the issue is recoverable through cleaning or requires membrane replacement.
Do membranes need cleaning right now?
Not all performance changes require immediate action—but certain thresholds indicate when cleaning should be performed.
Popular RO Membrane Troubleshooting Articles
Need Deeper Support?
Our team is here to help you troubleshoot, find the right products, and plan for your next change out.