If your RO system is in need of repair, our "RO Troubleshooting Guide" can assist you in diagnosing issues with your reverse osmosis (RO) water filtration system.
From the list below, select the problem you're experiencing. We provide possible solutions for that RO issue. Please understand that the solutions offered are given as a general guideline, and we strongly recommend you consult your specific RO systems’ owner’s manual and/or local water treatment specialist.
If you purchased your RO system or filters from ESP Water Products, our customer support reps are available Monday through Friday, 8 am to 5 pm (Central Time) to answer questions and troubleshoot over the phone at 1 (877) 377-9876.
This is an exceptional reverse osmosis drinking water system, renowned for its outstanding filtration performance. This RO unit ensures 50 gallons per day of filtered water Equipped with a premium T.F.C. reverse osmosis membrane, it incorporates a sediment pre-filter, carbon post-filter, and an in-line polishing carbon filter, guaranteeing quality drinking water for your entire household.
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RO Drinking Water Systems
Under-sink reverse osmosis filtration is an economical way to provide your household with clean, great-tasting drinking water.
Whether you're looking for an RO system with a proven record and reputation, one with a low price point, or a system that's easy to maintain, we offer a variety of options for you.
A little noise is common with air gap faucets. Check your owner's manual to be sure air gap is installed properly. Learn more about air gap vs. non-air gap faucets.
And some RO drinking water systems (such as the TFC-400-ESP) come with a facuet that can be used with air gap or non-air gap.
Air in systems may take up to two weeks to be purged from system under normal use.
2. Drain tube
Check drain line from faucetruns downhill to drain saddle clamp. Loops, bends, dips or kinks can cause noise.
Leaking Fitting
Potential Reasons
Solution
1. Fitting damaged or cracked
Replace fitting
2. Tubing not pushed securely into fitting or threads not properly installed
Check tubing installation & thread installation.
RO System is Continually Running
Potential Reasons
Solution
1. Automatic shut off valve not working
Replace automatic shut off valve – be mindful of where the four lines are removed and reinstalled.
Replace the flow restrictor that matches membrane capacity
6. Membrane incorrectly installed
Check membrane installation instructions
Ice Maker Not Working
Potential Reasons
Solution
1. Shut off valve to ice maker not open.
Open shut of valve
2. Ice maker in handle in refrigerator in off position
Place in on position
3. No water in RO storage tank
Check RO unit
No Water Dispensed From Refrigerator Door
Potential Reasons
Solution
Reservoir in refrigerator is not full
Hold down refrigerator water dispensing handle for 2-3 minutes to draw water through system. If no water is produced check RO unit for water flow. Learn more about connecting your RO system to a refrigerator or ice maker.
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Proven, High-Quality System
Designer Chrome Faucet
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Advanced Filtration, Quick-Change Filters, & Conserves Water
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Frequently Asked Questions
Why is my reverse osmosis system not producing any water?
A few common culprits cause no water flow: the water supply could be turned off, the RO storage tank may be improperly pressurized (it should sit at 5–7 psi when empty), or a clogged pre-filter or membrane could be blocking flow entirely. Other possibilities include a closed ball valve on the storage tank, a crimped product line, or insufficient incoming water pressure, which needs to be at least 40 psi for the system to function properly. Checking pressure and filter condition first usually narrows down the cause quickly.
Why is water flowing slowly from my RO faucet?
Slow flow is most often caused by a clogged pre-filter or post-filter, low air pressure in the RO storage tank, or a membrane that's fouled and overdue for replacement. Incoming water pressure below the 40 psi minimum can also slow output significantly. If the system or filters are newly installed, allowing 4–6 hours for the system to fully pressurize and fill can resolve temporary slow flow on its own.
Why does my reverse osmosis water taste or smell bad?
Bad taste or odor usually points to an exhausted carbon filter, a membrane that's no longer rejecting dissolved solids effectively (typically below 80% TDS rejection), or a system that needs sanitizing due to bacterial buildup. It can also happen if the system sits unused for too long — RO water shouldn't go undrained for more than 5 days, since stagnant water in the lines can affect taste. Replacing the exhausted filter or membrane and running a sanitizing cycle usually resolves the issue.
Why does my RO system run continuously instead of shutting off?
A system that won't stop running is commonly caused by a malfunctioning automatic shut-off valve, low incoming water pressure, or low air pressure in the RO storage tank. It can also result from a ruptured storage tank bladder, a worn-out flow restrictor in the drain line, or a membrane that wasn't installed correctly. Checking tank air pressure and the shut-off valve first is the quickest way to diagnose the cause.
Why isn't my ice maker getting water from my RO system?
This usually comes down to the shut-off valve to the ice maker not being open, the ice maker switch inside the refrigerator being set to off, or the RO storage tank simply not having enough water available. If the fridge dispenser also isn't producing water, holding down the dispensing handle for 2–3 minutes can help draw water through the system; if nothing comes through, the RO unit itself should be checked for proper flow.
