16
Troubleshooting Guide For Your
Forbes Under Sink RO
No.
Symptom
Probable Cause
Solution
No water production, low
production
1. Tank Air Pressure too high
2. Water supply turned off
3. Low water pressure
a. Pre-filter clogged
b. RO Element damaged
or fouled
4. Plugged post-filter
5. Increased raw water
TDS level
6. Low raw water temperature
7. System undersized for
application
8. Flow restrictor clogged
1. Set tank at 5-7 psl (empty)
2. Turn on water supply
3. a. Change pre-filter
b. Change or replace
RO element
4. Change post-filter
5. Increase raw water
pressure
6. Increase raw water
pressure or install 10 feet
coil or ¼” tubing prior to
pre-filter in heated space
7. Replace element with
large capacity unit and/or
add second storage tank
8. Clean or replace flow
restrictor check for
biological or iron fouling
1.
Low or poor water quality
Bad Taste
1. All of the above with
particular emphasis on
flow restrictor, TDS, water
temperature and pressure
2. RO Water stood too long
in tank
3. Bacteriological fouling
4. Membrane fouling
a. Brine seal linking
b. Product water ‘O’ ring
leaking
c. Product water check
valve failure
1. Post-carbon filter
exhausted
2. System fouled by
micro-organisms
3. Storage tank bladder
ruptured
1. See number 1 solution
2. Open faucet to drain tank
3. Sanitise system
4. Requires further
pre-treatment and/or new
membrane
a. Check membrane
Brine seal
b. Check product water
‘O’ ring
c. Replace check valve
1. Change post-carbon
filter
2. Change post-carbon
filter/sanitize system
3. Replace bladder and
sanitise
2.
3.
