Installation and Service Manual
– Under-the-Counter Point of Use 5 Stage Reverse Osmosis System
Copyright © 2022 Applied Membranes, Inc.
All Rights Reserved.
Page 20
Water Pressure – The Most Important Factor!
RO systems run on water pressure. Therefore, your water pressure has the most direct effect on how well your
RO will perform. With sufficient water pressure (80 psi max.), your RO system will function well, give high
output with high removal rate, and fill up the storage tank quickly.
TDS Meter (Option) – How to Test Your Water Quality:
The TDS meter is used to test your water’s quality before and after the RO system. It also tells you when the
membrane needs to be changed.
Please follow instructions below:
Use 2 clean glasses, fill one glass with Tap water, fill the other glass with Product (filtered) water (rinse this
glass with filtered water several times to get an accurate reading). Remove the Sensor cap on the TDS meter
and rinse the meter sensor with filtered water several times, then Turn on the meter.
The meter will show “000” reading on its screen. Place the TDS meter into the Product water. Record Product
water’s TDS reading. Then do the same for the Tap water. Record the Tap water’s reading. Compare the 2
readings.
The Product water’s TDS should be about 3%-10% of your Tap water’s TDS. This is a normal range.
For example:
Your Tap water’s TDS: 100 ppm
Your Product water’s TDS should read within: 10% of 100ppm => 10ppm
This means that with 100 ppm input, the RO system has removed 90% of the contaminants (TDS) from the
source, leaving only 10% (10 ppm) residual TDS in the Product water. This is a normal range. Which means
the RO membrane is in good conditions.
If your Product water TDS reads less than 10%, that is a very good and normal reading.
You should test your water once or twice a year to monitor the membrane condition. As the membrane gets
depleted overtime, its rejection capacity will decrease. When this happens, the TDS in the Product water will
increase.
When your Product water TDS creeps up to 15%- 20% of input water’s TDS, it’s time to replace the
membrane.
How Long Does It Take to Fill Tank?
Depending on your water pressure, the standard tank will fill up in 2-3 hours. After the tank is filled, the RO will
shut off automatically.
Important!
Please TURN OFF the main cold water supply to the RO system when the unit is not in use during
a vacation or extended leave. During very cold or freezing weather conditions, please also TURN OFF the
main cold water supply and completely drain all of the water from the RO system and water storage tank.
How Full Can My Tank Fill Up?
Your water pressure and
temperature
will determine how full and how fast the storage tank will be filled up.
The stronger your input water pressure, the faster and fuller the tank can fill. If water pressure is low, the tank
will fill slower and will not fill up to its full capacity.
For a non-pumped RO system:
The 4* gallon tank will fill up according to your input water pressure as follows:
Input 70+ psi —> tank fills 3.1 gallon ( almost 100% full )
Input 60 psi —> tank fills 2.8 gallon ( about 88% full )
Input 50 psi —> tank fills 2.5 gallon ( about 70% full )
So, if your input water pressure is low, the tank will not fill up to full.
* 4-gal refers to tank’s total volume (air space & bladder). At 80-90psi, tank bladder’s capacity is around 3.2
gallons.