The treated water shows higher than acceptable Total Dissolved Solids (TDS) levels, indicating that the purification system is not adequately reducing dissolved salts and minerals.
Inspect the RO membrane for fouling, scaling, or damage and replace it if necessary. Verify the inlet water quality and optimize pre-treatment (such as sediment filtration, softening, or carbon filtration) to protect the RO membrane and improve TDS reduction.
Use a calibrated TDS meter to measure the TDS of both inlet and treated water. Record the values and compare them with system design specifications or acceptable limits to confirm that treated water TDS is indeed too high.
Shut down the system following safety procedures, depressurize the RO housing, and remove the RO membrane. Check for signs of fouling (discoloration, slime), scaling (hard deposits), or physical damage (tears, deformation). If performance is degraded or damage is visible, replace the membrane with a compatible new one.
Test the raw water for TDS, hardness, turbidity, iron, and other relevant parameters. Compare results with the RO system’s design limits. If inlet TDS or hardness is higher than expected, the RO may be overloaded, leading to higher TDS in the treated water.
Inspect pre-filters (sediment, carbon) and softeners or antiscalant dosing systems. Replace clogged cartridges, regenerate softeners, and verify correct antiscalant dosing. Proper pre-treatment reduces fouling and scaling on the RO membrane, improving TDS rejection.
Check feed pressure, recovery rate, and flow rates against manufacturer specifications. Adjust as needed to ensure optimal RO performance. After adjustments and any membrane replacement, run the system, flush as recommended, and re-measure treated water TDS to confirm it is within acceptable limits.