RO-45 model & RO-90 model - Slow and Little RO water output

The causes to the output problem are listed in the timeframe that you've owned your RO system. The grey background applies to systems in use for under 3 months and the white background applies to systems in use for more than 3 months.

When trying to identify the causes of slow and little output. Isolate the RO system by shutting off our dependant applicances. Such as: ice-maker, fridge and humidifier.

The causes are listed from the most frequent and probable to the least likeliest.


Feed water blocked

Make sure all lines to the RO system and within the RO head are not obstructed.

Make sure the feed valve, needle valve and tank ball valve are turned on.

Untangles the lines
Input pressure too low
If your home pressure is within the model's regulation. Make sure you have the right model.
Make sure all the feed valves are fully turned on or exchange for the appropriate model*
Wrong Line Installation
Using RO pictures and the Owner's Manual. Make sure all lines are correctly connected.
Rectify the problem
Excessive Demand
Make sure the model's capacity can support your humidifier, ice-maker and fridge's demand


Add Permeate Pump


Upgrade to a 14 gallon tank



Defective Membrane Housing

(Extremely Rare)

Waste water flows non stop down the drain line and no RO water.
Replace the membrane housing
Clogged Membrane
ASO Clogged
Check valve clogged
Replace the Check Valve


Tank pressure too low

Test the Pressure by using pressure. An empty 4 gallon tank should have 5 psi and empty 14 gallon tank should have 7psi.
Tank bladder ruptured
Locate the pressure valve on the tank to see if water is leaking out. If water is leaking out, then the tank needs to be replaced. Furthermore, a raptured tank tends to be very heavy compared to regular full tank.
Check valve clogged
Replace the Check Valve


Stage 5 filter clogged (Extremely Rare)

Replace stage 5 filter

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