Factory Step by Step Trouble-Shooting Guide
Note: this troubleshooting tek is for the spectrapure systems, not all mfg will use the same color codes or flow restrictor design. I also prefer to take my initial measurements with the prefilters installed. However, the theory should be about the same.. and remember to isolate the bladder tank when taking your measurements
spectrapure is the porche of RO units
This procedure has been written with the idea in mind that a retail customer has just returned a system to
a distributor's location and is asking for an immediate replacement, or repair. By following this guide you
should have sufficient information to determine the cause of the customer’s complaint and provide the
correct solution. We tried to keep this guide as simple as possible and avoided using technical terms. We
also start the guide with a visual inspection then proceed to more-involved troubleshooting, which
requires dismantling some parts of the system.
Eliminator 90 RO (See Page 5 for the 180 GPD system)
Low Water Production
The most common complaint from your customers will be a low product water flow rate from the RO
system. There are two local causes for this condition: low water pressure and/or low water temperature.
The next common cause for low production will be a clogged sediment and/or carbon pre-filter. The least
likely cause of low production is a fault with the RO membrane. By following the step-by-step procedures
listed below you will be able to determine the cause of the customer complaint.
The Following Tools are Required for Testing:
1- Operations Manual for the RO System
1- Measuring Cup or Graduated Cylinder in milliliters
1- In-line Thermometer
1- Pressure Gauge Kit ( PGK )
1- Chlorine Test Kit ( TK-CL-25 )
1- Conductivity Tester ( TS-T61 or TS-T71 )
1- 90 GPD Flow Restrictor ( FR- 90 )
1- 180 GPD Flow Restrictor ( FR-180 )
1 - Check the Location of the Product and Wastewater Lines
The easiest means of differentiating between the Product water port and the Wastewater port of the RO
membrane housing will be to locate the injection-molded stem that protrudes from the base of the Product
water port. This stem is clearly visible in the Owner's Manual and by visually inspecting the output end of
the membrane housing. (Also, most of the newer membrane housings have a BLUE retaining ring on the
Product water port and a YELLOW retaining ring on the Wastewater port).
Note: Tubing may be disconnected by holding down the retaining ring with your thumbnail and
pulling the tube straight out with your other hand. When you re-insert the tube, be sure the end
seats firmly into the bottom of the fitting and cannot be pulled out by hand.
If the BLUE and YELLOW tubing are in the proper locations, continue to Step # 2.
If the BLUE and YELLOW tubing are reversed, you have found the problem.
Solution: Reverse the connections of the blue and yellow lines. Be sure the Flow Restrictor is in the
2 - Inspect the Black Tubing between the Carbon Pre-Filter and the RO Membrane Housing
If the tubing is in good condition, continue to step # 3. If the tubing is pinched or deformed in any way, you
have found the problem. Solution: Replace the tubing.
3 - Check the Flow Restrictor
Remove the yellow tubing from the RO membrane housing. Look in the end of the yellow tubing.
If the Flow Restrictor is inside the end of the yellow tubing continue to step # 4.
If the Restrictor is missing, you have found the problem.
Solution: Install a new Flow Restrictor.
4 - Inspect the Flow Restrictor
Remove the Flow Restrictor from the yellow tubing. One end of the capillary tube is bonded to a plastic
insert. Inspect the bonding material for voids between the capillary tube and the plastic insert.
If the bonding material has developed a void or the capillary tubing is missing, you have found the
Solution: Replace the Flow Restrictor.
Inspect the internal diameter of the capillary tube. The ends of the tubing should have clean cuts without
burrs at either end. The internal diameter should be open throughout the length of the tubing and you
should be able to blow a slight amount of air through the tubing.
If the tubing is deformed, if either end has burrs, if a particle or a foreign substance is blocking the internal
diameter of the tubing, or if the tubing was crimped, you have found a problem that may have
permanently damaged the membrane.
Note: Inform the customer that the membrane can be easily damaged if any of these conditions existed
for even a very short period of time.
Solution # 1: If the tubing has burrs or is crimped near the end:
Cut off the damaged end of the tubing with a sharp razor blade or Exacto blade at a 45 to 60 degree
angle, then re-install the Flow Restrictor into the yellow tubing and insert the yellow tubing into the waste
water port on the RO membrane housing.
Solution # 2: If the capillary tubing is damaged beyond repair, replace the Flow Restrictor.
Testing the System
You are now ready to start testing the system for the proper flow rates from the product and waste lines
and to determine the condition of the sediment and carbon pre-filters and the RO membrane.
1 - Prepare System for Testing
Insert the "tee" of the Pressure Gauge Kit between the "OUT" of the carbon filter and the "IN" of the RO
membrane housing. (If an Auto Shut-Off Valve has been installed on the unit, insert the pressure gauge
kit between the "OUT " of the ASO and the "IN" of the RO membrane).
Attach the input line of the system to a water source that has the In-line Thermometer installed.
Slowly turn on the water until the water supply valve is on full (< 80PSI).
Allow the air to bleed from the system for a few moments.
Record the water temperature. (__________)
Record the water pressure reading on the pressure gauge. (__________)
This would also be a good time to test for chlorine leakage through the carbon pre-filter. Use the Chlorine
Test Kit, which is accurate to < 0.2 PPM. If "any" level of chlorine is present in the wastewater stream the
RO membrane could have been damaged. The carbon pre-filter will need to be replaced after testing is
complete and possibly the RO membrane. (This test assumes that you have a chlorinated water source).
Turn off the water. Allow the pressure to bleed off. Unscrew the sediment and carbon pre-filter housings
and remove both filters. Re-install the empty housings.
Note: All of the remaining tests will be performed without the pre-filters installed!!
2 - Testing the Condition of the Pre-Filters (Calculating the % of Pressure Drop)
Slowly turn-on the water until the water supply valve is on full (< 80PSI).
Allow the air to bleed from the system for a few moments. Record the water pressure reading on the
pressure gauge. (__________)
Compare the water pressure before and after removal of the prefilters.
Divide the pressure reading after the filters were removed by the pressure reading before they were
removed. Subtract 1 from the result then multiply by 100. [ ( ( Pafter / Pbefore ) - 1 ) X 100 ] This is
the percentage of pressure drop across the pre-filters. If the pressure reduction is greater than 15%, both
of the pre-filters should be replaced, after all testing is completed.
(This would be a good opportunity to educate the customer on the benefits of having the Pressure Gauge
Kit (# PGK) permanently installed on their RO system. If it is suspected that the customer has low
pressure, a Pressure Gauge Kit plus a Booster Pump (# BPHF-MO-115) will be required for the proper
operation of the system).
3 - Test the Membrane Flow Rate
We are now ready to check the product and wastewater flow rate from the RO membrane. After
completing the pre-filter tests, the tap water should still be turned "on" and the pre-filters removed
from the system.
If you are confident that the existing Flow Restrictor is in good condition and has passed your prior
inspection and testing, you may continue to the next test. If the condition of the Flow Restrictor is suspect,
we would recommend removing the customer's Flow Restrictor and installing your test restrictor that was
supplied for this test.
With the water on full (< 80 PSI) measure the water volume from both the waste and product lines
individually for one minute each.
Measure and record the Milliliters per Minute from the Product line. (__________)
Measure and record the Milliliters per Minute from the Wastewater line. (__________)
At this point in our testing we will not concern ourselves with the Wastewater volume. You may use the
existing restrictor if the Wastewater flow is in a range between 300 milliliters per minute at 40PSI @ 50F
and 950 milliliters per minute at 60PSI @ 77F.
For the purposes of this test, we would expect that most systems will be used under average conditions
at approximately 50 PSI @ 60 F. If your conditions are close to this assumed average condition, we
would recommend using an FR-90 Flow Restrictor cut to approximately 8 inches total length for this test.
Note: If the Wastewater volume is less than 4 times the Product water volume (using the customer’s
original Flow Restrictor), the membrane may have been damaged due to insufficient Wastewater flushing
effect caused by improper adjustment of the Flow Restrictor. Inform the customer that operating the
system at less than a 4 to 1 ratio will cause premature fouling of the membrane and a loss of water
production. This condition will also void any warranty on the RO membrane. (Before recommending a
membrane replacement, complete the test procedure).
4 - Proceed to the "Membrane Output Calculation Guide" in the Owner's Manual
The result of your calculations will show the "Expected" GPD production rate from the system after taking
into account the water temperature and water pressure variations.
Unfortunately, most customers will not be aware of the effects that water pressure and temperature have
on RO membranes. It may be necessary to explain the calculations to the customer at this time. If the
"expected" GPD production rate is within 15% of the actual flow rate, the membrane is considered to be in
This completes our inspection of the system, pre-filter diagnostics and the "expected" flow rate
If the customer's questions relate to product water purity, continue to the following section.
1- Tools Required for Testing
Conductivity Tester, TS-T61 or TS-T71
Before proceeding with the following test procedure please follow all of the previous test procedures and
verify that the water pressure is adequate. Also confirm that the conductivity tester is calibrated correctly
and is in good working order. (See the owner's manual for the tester.)
Allow the system to operate for 10 to 20 minutes without interruption and verify that the pressure is
greater than 40 PSI. Direct the product and wastewater streams to a drain.
Most TDS testers include a reservoir cap for retaining the water that is to be tested. Be sure the reservoir
is clean by rinsing it thoroughly at least three times with the product water as it drips directly from the
product water line, before attempting to take the conductivity reading. After filling and discarding the water
three times record the reading. (__________)
Turn on a tap water faucet and let it run for a minimum of 30 seconds. Follow the step above and record
the conductivity reading. (__________)
2 - Calculate the Percentage of Rejection
Subtract the RO product water conductivity (X) from the tap water conductivity (Y). Divide the result by the
tap water conductivity (X) then multiply by 100. This is the % of rejection from the RO membrane.
[ ( (X - Y) / X ) x 100 ]
Under normal water conditions and at 60 PSI water pressure, the expected rejection rate from a new RO
membrane should be greater than 97%, although there are several other factors that may affect the TDS
level of the product water.
For example, if soda lime softening (Calcium Hydroxide) is used in the municipal water supply to raise the
PH, a high percentage of OH will pass through the membrane and cause the conductivity to be higher
than normal in the product water.
There are many factors that will affect the operation and rejection characteristics of an RO system. A few
among many are: hydrogen sulfide, iron, bacteria, excess hardness, very low or high PH, ammonia,
tannins etc. If you are still in doubt after completing all of the test procedures please call the SpectraPure
Technical Support Line at 1-800-xxx-xxxx, Ext x.
Eliminator 180 RO
The Eliminator 180 GPD System incorporates two 90 GPD RO membranes. All of the previous steps
used for evaluating the 90 GPD systems are valid in this procedure except for the items listed below. You
will be testing the product water rate for each of the RO membranes independently in order to determine
their condition. The membranes are in series with the wastewater from the first membrane feeding the
input of the second membrane. You will need to remove the product lines from each membrane housing
and test the individual conductivities in accordance with the Water Purity paragraph above.
1 - Testing Conductivity for 180 GPD System
After the system has been operating for 10 minutes or more, remove the blue product lines from each
membrane at the "tee".
Follow the instructions under the Water Purity paragraph above.
Record the numbers and calculate the results. If either membrane has a rejection rate of less than 94%,
we would recommend replacement of the membrane.
Reconnect the product lines.
2 - Test the Membrane Flow Rate
After the system has been operating for 10 minutes or more, remove the blue product lines from each
Follow the instructions under “3 - Test the Membrane Flow Rate” above and measure the product rate
from each membrane independently.
Each of the membranes should be within 15% of the "Expected" GPD flow rate. If either membrane were
below the expected production rate, we would recommend replacing that membrane.
SpectraPure Inc. Latest Rev: 2003-01-09