RO Troubleshooting Guide

RO Troubleshooting Guide

This sometimes happens when you first install your new filter cartridge. The cloudiness is harmless, compressed air. To remove it, the cartridge needs to be flushed for 5-9 minutes. If your water pressure is low then it may need to be flushed for longer.

Nothing’s wrong with the filter. It’s just that the filter cartridge hasn’t been flushed for long enough and there’s some leftover carbon powder from the manufacturing process. It’s harmless and easy to fix. Just open the tap for 5-9 minutes. This will fully activate the system and clear it.

Such cases are very rare but can happen. It might be caused when the system is moved or by sudden changes in water pressure. Solution: immediately shut off water supply by closing kitchen or main water supply valve and notify your product distributor or a plumber who installed your system.


For systems with tank ‐ check if water supply valve or tank valve is open or whether the tank is not empty.


For systems without tank‐ check (by unscrewing the spout) whether water pressure in your pipes is sufficient. If it is, the reason for the slow filtration of water might be clogged pre‐filters or worn diaphragm


Other causes:‐ lack of pressure at the bottom of the tank, used cartridges or osmotic membrane.


Make sure that water supply pressure in your pipes is sufficient. Pressure drop has directly proportional effect on the performance of the membrane. The lower the water pressure, the lower the production of purified water.


If low water pressure in the system remains constant you must install an additional booster pressure pump, such as: AFXPOMP or AFXPOMP‐4.


Other causes: old filter cartridges and/or clogged RO membrane as well as too low temperature of tap water.


This can be caused by faulty 4‐way valve and as a result the valve does not shut off the water to the RO membrane.


Also, check if there is sufficient water pressure in your pipes and system (minimum of 2.8 bar or 40.6 PSI). If the pressure is lower, install booster pressure pump AFXPOMP or AFXPOMP‐4.


It is also possible that your system's 4‐way valve may be damaged by dirt or sediment particles that got into the system during installation. In such cases, 4‐way valve needs to be disassembled and cleaned up. If the problem persists, replace the valve with a new one.


Another reason could be damaged seal of one of membranes forming the 4‐way valve.


And finally, 4‐way valve can be clogged by large amounts of ions of calcium, magnesium and iron. In such cases, 4‐way valve needs to be disassembled and cleaned up. If the problem persists, replace the valve with a new one.


The reason for high TDS may be inaccurately flushed RO membrane. New RO membrane needs to be flushed immediately after installation. In order to thoroughly flush the membrane, fill the whole tank (12 liters/3.2 gallons), then empty the tank completely. Repeat it at least once.


WARNING! Do not drink the first two parts of water.


Another reason, the membrane may be installed incorrectly inside of the membrane housing. Remove the membrane from the housing, check for damaged O‐rings: at the top and two o‐rings on the bottom. O‐rings should be re‐greased with petroleum jelly and installed again inside the housing.


Water pressure is too low: Reverse Osmosis systems can work properly with pressure above 2.8 bar (40.6 psi). When the water pressure in a system is below 2.8 bar (40.6 psi) install booster pressure pump AFXPOMP or AFXPOMP‐4.


Water pressure is too high: If water system pressure is above 6 bar, pressure regulator must be installed. High inlet water pressure can damage the working components of RO system.


Manufacturer and distributor do not assume any liability for damage caused by water pressure surges in plumbing installations or higher nominal pressure (over 6 bar or 87 psi).


Pressure regulators ADV‐REG_K, ADV‐REG‐CR_K, PLV‐0104‐50_K or PLV‐0104‐80_K can be purchased separately.


Shorter life‐span of RO membrane can be affected by many factors:


Unsuitable parameters of inlet water (high concentration of calcium, magnesium and iron). These basic parameters must be met by inlet water for RO systems ‐ refer to "Required water parameters for RO systems" section.


Sediments and iron compounds clog microscopic pores of RO membrane what leads to membrane damage and shortening its life.



Another reason for premature failure of RO membrane may be timeous maintenance of equipment. Pre‐filter cartridges should be replaced at least 3‐6 months. Failure to conduct these measures will result in membrane damage.


Finally, inaccurate flushing procedure of carbon cartridge may result in carbon particles clogging RO membranes film.


Osmotic membrane: sediment scaling and iron compounds clog microscopic pores of the membrane which in turn leads to damage of the membrane and shortening its service life.



Four‐way valve: controls the flow and water intake for the water storage tank (pressure equalization). The valve will automatically shut off water supply to the diaphragm (the device does not receive water). Sediment scaling and iron compounds may contribute to improper functioning of the valve. Overloaded valve may not complete be closed resulting in a continuous flow of water to the drain and consequently attribute higher water bills. Four way valve should undergo a cleaning process at least every six months.



Flow restrictor: reduces water consumption in RO Systems by producing adequate working pressure inside the membrane. Poorly connected or blocked, may cause damage to the osmotic membrane. Flow restrictor must be replaced from time to time, but not less frequently than every 18 months.