Why Does the Water From My RO System Seems Cloudy?
The water out of my RO system seems milky or cloudy, what is the reason for this issue?
This is generally caused by trapped air within the RO system. However, it will not affect the quality of your water. The cloudiness should disappear within a minute after water sits in a glass. This is a normal occurrence with a newly installed RO System or after a filter change. You can release the air from your RO system by draining the tank 1 to 2 more times or using RO makes humming noise air release instructions in your system manual (see below). Read more
Common Causes to Premature Membrane Failure:
There are 4 common causes that lead to premature membrane failure:
- Failing to replace the 3 pre-filters as frequently as needed:
- If you’re on city water: The over-depleted carbon pre-filters allow the chlorine to get through and damage the membrane.
- If you’re on private well water: The overloaded pre-filters allow excessive sediments and particles to get through and clog up the membrane surface. Read more
What to Do When Leaking From Ultra Violet Light Occurs
If you notice a leak at the electrical wires of the UV light after installing your RO unit, the internal glass sleeve inside the UV housing may have been damaged during shipping.
Please follow the steps below to determine if the internal glass sleeve is damaged.
- Shut off the feed water line to the RO unit.
- Shut off the tank ball valve by turning the blue cap on the tank ball valve 90 degrees. This step is not required for the Countertop Models. Read more
TDS Reading Is Higher Than Normal
If the Pure water TDS is higher than normal after 1-2 full tank flushes, please review the possible reasons below.
- Membrane was not inserted > Put membrane into housing.
- Membrane is inserted incorrectly > Re-insert membrane correctly. Refer to Manual.
- Tap water source water has very high TDS and/or contains certain heavy dissolved elements resulting in TDS higher than usual. Read more
RO Storage Tank Takes A Long Time To Fill
If the RO unit takes a long time to fill the storage tank, please review the possible factors below.
- Insufficient water pressure (below 40 psi for non-pump systems) > Increase house water pressure, if possible or add an appropriate pump to system. Please contact an APEC Representative for assistance.
- Low water temperature (below 77 degree F) > Increase house water pressure or add pump to compensate for low (cold) water temperature. Temperatures can affect Read more
Tank is full of water but there is very little or no water coming out the faucet.
If you are experiencing very little or no water coming out the drinking water faucet, but have a full tank, the first thing to check is the tank. The tank may be low on air pressure or have a ruptured (torn) bladder.
Locate the blue or black plastic cap on the bottom side of the tank. Fully unscrew the cap to expose the metal air stem valve. Read more
Sluggish Or Very Low Water Flow At RO Dispensing Faucet
Once the system is installed, if you experience sluggish or very low water flow out of the RO dispensing faucet, please review the possible factors below.
- Insufficient water pressure (see RO Basics for explanation) > Check water pressure. If the water pressure is too low for this chosen RO model, either increase your water pressure or add pump to RO system. Please contact an APEC Representative for support. Read more
What to Do When Permeate Pump is Not Clicking
When operating properly, the Permeate Pump will click once every 2-4 seconds. When the pump clicks, it is forcing the pure water into the tank and forcing the brine water into the drain. If your system is no longer filling the tank, or you no longer hear the pump clicking, you may have clogged filters or a defective permeate pump.
The instructions will guide you in determining if the pump is defective. Please use the the diagram for reference.
- Turn off the feed water line to the RO unit, by shutting off the needle valve or main water line.
- Close off the tank by turning the blue cap on the tank ball valve 90 degrees. Read more
RO Unit Makes Humming or Vibrating Noise
If you are experiencing a humming or vibrating noise with your RO (reverse osmosis) system, there may be air bubbles that have accumulated inside the unit or Check Valve.
Please follow the steps below to purge the air bubbles out the unit: Please refer to Figure 1.
- Close the tank’s ball valve, by turning the blue cap 90 degrees.
- Tilt the RO system to the right. Put something under the 3rd filter housing to keep RO tilted. This helps dislodge the air bubbles from the Check Valve. Read more
Bad Taste To RO Pure Water
If you are experiencing a bad taste in the Pure Water, the RO Membrane or Stage 5 Carbon filter maybe depleted and needs to be replaced. Please follow the steps below to determine if the membrane and or stage 5 carbon filter needs to be replaced.
- Fill up a clean cup of water from the RO Unit.
- Take a Pure Water TDS reading with the supplied TDS Digital Meter that came with the RO unit. Read more

