Dometic RO400 User manual

RO400
RO400B
RO400C
RO400CV
RO400BC
RO400BCV
RO600C
RO600CV
8229016-90
SERVICE MANUAL
REVERSE OSMOSIS
WATER PURIFIER
Rev. 2011-12-21
JON-KB 1151
WP 05
%.

- 2 -
CONTENTS
SERVICE PROCEDURES FOR SAFETY____________ 3
SAFETY INFORMATION ________________________ 3
TECHNICAL FACTS____________________________ 6
WIRING AND ELEMANTARY DIAGRAM____________ 8
SCHEMATIC DIAGRAM _________________________ 9
PRODUCT DESCRIPTION ______________________ 10
LOCATECOMPONENTS............................10
INDICATOR LIGHTS AND BUTTON....................11
INLET WATER SYSTEM .............................11
PUMPSYSTEM ...................................12
MEMBRANESYSTEM..............................12
PURIFIEDWATERSYSTEM .........................13
FLUSH SYSTEM...................................13
WATER QUALITY MONITORING ......................14
LOWPRESSURERESTART .........................15
DISPLAY TIME IN OPERATION . . . . . . . . . . . . . . . . . . . . . . . 16
DISPLAY NUMBER OF LOW PRESSURE STOPS . . . . . . . . 16
RESET FAULT INDICATION ..........................16
SERVICE RECORDS __________________________ 17
DATA COLLECTION AT INSTALLATION.................17
DATA COLLECTION AT SERVICE . . . . . . . . . . . . . . . . . . . . . 17
TROUBLESHOOTING _________________________ 18
LED INFORMATION GUIDE ..........................18
FAULT IDENTIFICATION GUIDE . . . . . . . . . . . . . . . . . . . . . . 20
COMMENTS......................................31
SERVICE____________________________________ 32
TOOLS FOR SERVICE ..............................32
PERFORMING A DIODE TEST........................32
REMOVE COMPONENT FROM A QUICK CONNECTOR . . . 32
CHANGINGINLETVALVE...........................32
CHANGINGFLUSHVALVE ..........................33
CHANGING FILTER CONTAINER . . . . . . . . . . . . . . . . . . . . . 33
CHANGING TOP SECTION OF PREFILTER ASSEMBLY . . . 34
CHANGING PRINTED CIRCUIT BOARD................34
CHANGING PRESSURE SENSORS . . . . . . . . . . . . . . . . . . . 35
CALIBRATING PRESSURE SENSOR . . . . . . . . . . . . . . . . . . 35
CHANGING PURIFIED WATER OUTLET................36
CHANGINGDRIVINGBELT..........................36
CHANGING MOTOR................................36
CHANGING PRESSURE REGULATING VALVE . . . . . . . . . . 37
FITTING PUMP- / MEMBRANE SERVICE KIT............38
FLUSHING .......................................40
CALIBRATION OF CONDUCTIVITY....................40
SYMBOLS
The following symbols are used throughout the manual:
Indicates a potentially hazardous situation, which, if not avoided, could result
in death or serious injury.
Indicates a potentially hazardous situation, which, if not avoided, may result in
minor or moderate injury.
Used without the safety alert symbol indicates, a potentially hazardous situation which, if not avoided
may result in property damage.
Information
Step-by-step instructions
For information regarding installation, use, maintenance and service that is usually performed
by the end user, please refer to the user manual (supplied with the product).
This manual is valid from .............
Concerning RO400 / RO600 manufactured before this point in time, we refer to the previous
version of the Service Manual. Some sections are however be more accurate in this document.
CAUTION
!
WARNING
!
CAUTION

- 3 -
SERVICE PROCEDURES FOR SAFETY
To prevent personal injury and/or damage to property, it is important to follow sound procedures when carrying out servicing
work. The list below does not attempt to set out all such procedures, but gives some examples.
Do not attempt to repair the water purier if you are uncertain of your ability to complete the job in a safe and satisfactory man-•
ner.
Before doing any servicing work or moving the water purier:•
Remove the electrical plug from its socket, or switch off the electrical supply to the whole building, or remove the correct-
fuse for the electrical circuit to which the product is connected.
Turn off the supply of water to the product.-
Never do anything which could impair the proper functioning of any safety device or feature.•
Use only those spare parts which the spare parts catalogue species as suitable for the purpose. Substitute spare parts can result •
in the safety standards being breached.
Earthing: The standard colour for earth wires, needed for safety, is green with yellow stripes. Earth wires must not be used as•
conductors. It is very important that the service engineer should reconnect all earth connections before completing the servicing
work. Any failure to do so is potentially hazardous.
SAFETY INFORMATION
Read these instructions before installing or servicing. Study the safety precautions and be aware of possible safety hazards
-
formed according to these instructions and servicing by service personnel only.
INSTALLATION
Check that the inlet water to the water purier fullls the •
requirements, see “TECHNICAL FACTS”.
The water purier should be connected to an earthed electri-•
cal supply. As some operations require the power supply to
be temporarily interrupted, it is best to connect using a plug
that is also easily accessible after installation. Permanent wir-
ing to the electrical supply may only be carried out by a quali-
ed electrician and should be performed with a safety switch.
Incorrect installation can result in personal injury and/or dam-
age to property which are not covered by any warranty.
Plumbing work should be performed by a qualied plumber. •
If you do the installation yourself, you must acquaint yourself
with the applicable standards (e.g. EN1717) and adhere to
them.
A hose for feed water is supplied with the water purier. •
This hose should be used and any old hose-set should not be
reused.
It is important for the purier to be installed upright on a •
horizontal surface that can take the load, and that hoses and
cables are neither tensioned nor get jammed when moving the
purier, e.g. during installation and cleaning.
If the feed water is classed as unt, have the puried water •
checked after installation. After this, test the puried water
once a year or if there is any change in the taste or odour.
Do not drink/use the water if the results are unsatisfactory.
Contact your dealer.
When the water purier is new, the puried water may not be •
used until ushing and calibration have been completed.
Calibration of the water purier may only be carried out: •
- The rst time the water purier is taken into use.
- If the inlet water quality changes (e.g. when moving).
- After replacing the membrane.
- After exchanging the water quality sensor or printed circuit
board.
The reverse osmosis technique reduces most substances•
extremely effectively. For this reason, the content of those
substances that normally protect pipes, tanks, valves, etc.,
are very low in the puried water from the water purier.
Consider the risk of corrosion and elution when chosing
materials in peripheral equipment in contact with the puried
water.

- 4 -
CHILD SAFETY
Do not let children play with the water purier.•
Never leave packaging material lying around so that children•
can play with it.
USE
The water purier is intended to produce water for applica-•
tions that require puried water.
Puried water should only be used when the control panel’s •
lights II or III (purication levels) are lit. It can take up to 60
seconds before the water purier indicates good water quality.
The water purier must be connected to water and electricity •
in order for the automatic ushing system to work. Automatic
ushing takes place approximately every 12 hours.
The top of the water purier should not be used as a place for •
storing anything.
Do not use puried water in aluminium vessels. There is a •
risk of corrosion of the vessel and a higher concentration of
aluminium in the puried water.
Do not change or modify the water purier in any way. This •
can result in personal injury and/or damage to property which
is not covered by any warranty.
If the water purier is to be disconnected from water and •
electricity for an extended period (several days), it should be
stored, see “STORAGE” in the user manual. This also provides
protection against freezing.
The water purier may not be used without prelters (un-•
less otherwise specied in maintenance procedures, see user
manual). It could be seriously damaged.
If the water purier contains chemicals from maintenance •
procedures, it must be ushed before the puried water may
be used, see “FLUSHING” in the user manual.
Once a month, check that the connections are watertight.•
Leaks outside the water purier cannot be detected by the
internal safety system. If leakage occurs, immediately switch
off the water supply and break the current to the product by
pulling the plug out of the wall socket or remove the correct
fuse in the electrical distribution board.
If the mains lead has been damaged in some way, it must be•
replaced by a qualied person to avoid damage or injury.
REGULAR CARE OF THE WATER PURIFIER
Once a month, check that all the connections are in place and•
are watertight. Wipe off any condensation that has collected
on the base plate.
Make sure that you always replace prelters in time. The •
lifetime of the prelters depends on your feed water.
Depending primarily on the hardness of the feed water and•
its content of microorganisms, the water purier should be
cleaned when the ow is reduced or at least every 6 months
and disinfected if the water smells or tastes bad.
SAFETY INFORMATION
RO400A/RO400B
The model name for RO400A is actually RO400 (without
letter). The A is added in this document to distinguish from
RO400 when used as a family name.
RO400A and RO400B are domestic models. Most functions
and features are however common with the commercial (C-)
models.
The water purier is designed to produce the quantity of wa-•
ter normally required for cooking, drinks, washing dishes and
general household duties.
The water purier may only be installed with the drinking •
water faucet supplied with the product.
The water purier must not be connected to supply the whole •
dwelling with water. Neither may the water purier be in-
stalled in connection with valves, switches or tanks. Be aware
of the risk of corrosion in water pipes and water heaters.
Any faults that arise in a water purier that has been incor-•
rectly installed are not covered by any warranty.
RO400B/RO400BC/RO400BCV
(BRACKISH MODEL)
Brackish (B-) models are used when the inlet water has a high
content of salt, more than the maximum level for normal, sweet
water models, up to a maximum of 7,500 ppm (mg/l).
It might be wise to chose the brackish also if the salt content is
just below limit, if it is known that the value varies widely over
time.
Sea water cannot be puried with these models, even if the
purication technology is the same.
Especially important remarks for the brackish models:
It is very important that the purier is always connected to •
water and electricity. Brackish water often contains organic
materials that will increase the bacteria growth. To prevent
this an automatic ush is performed approximately every 12
hour.
Concerning the installation, the material in all components at•
the inlet- and drain connections must be resistant to corrosion,
for example in plastic or stainless steel.

- 5 -
6
1
2
3
4
5
8A
9
13
16
10 11 12
14
7
PRODUCT OVERVIEW
* Supplied with domestic models RO400A and RO400B
** Alternative connector, replacing faucet
*** Supplied with RO400CV, RO400BCV/RO600CV
Bracket for reject water hose1
Reject water hose, rubber, i.d. 22 mm2
Hose clips (2)3
Hose for inlet water, 3/4” BSP nut4
Filter spanner5
Information decal6
Control panel7
a) Puried water faucet *8
b) Connector with shut-off valve **
Puried water hose, PE 3/8”9
Filter container I10
Base plate11
Filter container II12
Indicator lights *13
Pure water rinse function (-CV) ***14
Pure water rinse hose ***15
Hose holder for air-gap ***16
15
8B

- 6 -
TECHNICAL FACTS
Data
Height 466 mm
Depth 395 mm
Depth with hoses 460 mm
RO400CV/RO400BCV/RO600CV 470 mm
Width 225 mm
Weight (on delivery) 29 kg
Weight (lled with water) 33 kg
Electrical connection 230 V, 50-60 Hz, 10 A
earthed supply
Working range
Ambiente temperature 2 - 35°C
Relative humidity (RH) 25 – 95 %
Sound level when installed <60dB(A)
undersink cupboard
MODEL
DATA
RO400 RO600
A B C CV BC BCV C CV
Capacity *
(at water temperature 15 °C, 750
ppm), litres/minute (± 0,5)
3.1 3.1 3.5 3.0 3.1 3.0 5.2 4.5
Recommended max. usage,
litres/minute 100 100 1800 1500 1500 1500 2800 2400
Total power consumption (W) 530 530 530 530 530 530 720 720
Starting pressure level (bar) 0.5 0.5 3 3 0.5 0.5 3 3
Stopping pressure level (bar) 4.5 2 4.5 4.5 2 2 4.5 4.5
Water efciency during operation 50-60% 50-60% 60-70% 50-60% 50-60% 50-60% 60-70% 60-70%

Inlet water ow, litres/minute >8 >8 >8 >8 >8 >8 >10 >10
Inlet (dynamic/owing) water
pressure, MPa (bar)
0.15-1.0
(1.5-10)
0.15-1.0
(1.5-10)
0.15-1.0
(1.5-10)
0.15-1.0
(1.5-10)
0.15-1.0
(1.5-10)
0.15-1.0
(1.5-10)
0.20-1.0
(2-10)
0.20-1.0
(2-10)
Water temperature, °C 2-35 2-30 2-35 2-35 2-30 2-30 2-35 2-35
Chemical **
Conductivity, mS/m <200 <1300 <200 <200 <1300 <1300 <200 <200
Salt (TDS), mg/l (=ppm) <1500 <7500 <1500 <1500 <7500 <7500 <1500 <1500
Chloride (Cl-), mg/l <900 <4500 <900 <900 <4500 <4500 <900 <900
Cloudiness Slight/
distinct
Slight/
distinct ------
Turbidity, FNU <1.0 <1.0 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
pH 4-10 4-10 4-10 4-10 4-10 4-10 4-10 4-10
Calcium (Ca2+) and
Magnesium (Mg2+), mg/l <140.0 <140.0 <140.0 <140.0 <140.0 <140.0 <140.0 <140.0
Hardness (°d) <20.0 <20.0 <20.0 <20.0 <20.0 <20.0 <20.0 <20.0
Iron (Fe2+), mgl/l <5.0 <5.0 <1.5 <1.5 <1.5 <1.5 <1.0 <1.0
Iron (Fe3+), mgl/l <0.3 <0.3 <0.3 <0.3 <0.3 <0.3 <0.3 <0.3
Manganese (Mn2+), mg/l <0.8 <0.8 <0.3 <0.3 <0.3 <0.3 <0.3 <0.3
COD-Mn: O2 , mg/l <10.0 <10.0 <5.0 <5.0 <5.0 <5.0 <5.0 <5.0
Microbiological
Heterotrophic bacteria, 48 h <1000/ml <1000/ml <1000/ml <1000/ml <1000/ml <1000/ml <1000/ml <1000/ml
Coliform bacteria <10/ml <10/ml <10/ml <10/ml <10/ml <10/ml <10/ml <10/ml
E. Coli <1/ml <1/ml <1/ml <1/ml <1/ml <1/ml <1/ml <1/ml
* Capacity is a function of temperature; higher temp - higher ow.
** Higher values require an additional pre-treatment

- 7 -
Examples of rejection for substances which may be present in water
 %
Turbidity (cloudiness) >99
Colour rating >99
Cations/Metals
Sodium >96 >92*
Potassium >97
Calcium (hardness) >99
Aluminium >99
Iron >99
Manganese >99

Copper >99
Lead >99
Zinc >99
Mercury >99
Cadmium >99
Chrome >98
Nickel >99

Fluoride >99
Chloride >98 >95*
Nitrate >97
Sulphate >97
 %

Heptane, octane, decane, etc. >98
Benzene, toluene, xylene,
Ethyl benzene, etc. >99
Diesel oil >99

PAH >99
Chlorinated hydrocarbons
Compounds which can form
when water is chlorinated >99

Trichloromethane >60
Bromodichloromethane,
dibromochloromethane,
tribromomethane >99

PCB >99

Heterotrophic bacteria >99
Coliform bacteria/E.Coli >99
* RO400B/RO400BC/RO400BCV
Sodium and chloride are not separated to the same extent when salt content (TDS / conductivity) is
high in the inlet water, which is normally the case when B-models are used.
TECHNICAL FACTS

- 8 -
WIRING AND ELEMANTARY DIAGRAM
4
3
2
1
4
3
2
1
1 2 3 44321
N L
1 2
1
2
3
1 2 3 5
21 1 3
1
3
1
4
2
S2
M
D E F
G
FS
LP HP
TDS
NT
Electronic
PCB
7
6
8
U3
U1
AIF
0
123
0
2 5 55 52 5 5
3 2 1
123
4
C
4
9
5
5
2
9
4
4
2
S1
S
9
4
44
S
CG
A
B
* *
* *
N4
L2
1550158 1
* = Un
AI
F
C
=
CG
M
=
FS
HP
LP
NT
S1
S2
S3
TD
S
4
3
2
1
4
3
2
1
1 2 3 44321
N L
1 2
1
2
3
1 2 3 5
21 1 3
1
3
1
4
2
S2
M
D E F
G
FS
LP HP
TDS
NT
Electronic
PCB
7
6
8
U3
U1
AIF
0
123
0
2 5 55 52 5 5
3 2 1
123
4
C
4
9
5
5
2
9
4
4
2
S1
S
9
4
44
S
S
S3
CG
CG
0
3
0
~~
A
B
Timer
* *
* *
L2
N4
1550159 1
Orange
Green
Yellow
Red
Grey
Black
Yellow/Green
Blue
Brown
Not specied
Wire Colour
1
2
3
4
5
6
7
8
9
0
Orange
Green
Yellow
Red
Grey
Black
Yellow/Green
Blue
Brown
Not specied
Wire Colour
1
2
3
4
5
6
7
8
9
0
AIF Anti-Interference lter (RFI)
C Capacitor
CG Chassis Ground
M Motor
FS Floater Switch
HP Outlet pressure sensor (High Pressure)
LP Inlet pressure sensor (Low Pressure)
NT Net Terminal
S1 Inlet valve
S2 Flush valve
TDS Conductivity sensor (Total Dissolved Solids)
AIF Anti-Interference lter (RFI)
C Capacitor
CG Chassis Ground
M Motor
FS Floater Switch
HP Outlet pressure sensor (High Pressure)
LP Inlet pressure sensor (Low Pressure)
NT Net Terminal
S1 Inlet valve
S2 Flush valve
S3 Pure water rinse valve
TDS Conductivity sensor (Total Dissolved Solids)
RO400, RO400B, RO400C, RO400BC, RO600C
RO400CV, RO400BCV, RO600CV

- 9 -
SCHEMATIC DIAGRAM
Outlet pressure
sensor
Pressure regulating
(relief) valve
Loop pump for high
internal recirculation
Inlet (water) pressure sensor
(low pressure switch)
Flush valve, solenoid,
normally closed (top) with
ow restrictor
REJECT
WATER
Inlet valve, solenoid,
with screen lter
INLET
WATER
Membrane (-element,
Reverse Osmosis: RO,
Thin Film Composite: TFC)
RO400-models:
Particle lter
and Activated
Granulated Carbon
lter (GAC)
Check (non-return) valve
puried water
PURIFIED
WATER
Pressure
accumulator valve
Conductivity sensor (TDS)
RO600-models:
Carbon block lter
(two identical in
parallell ow)
High pressure pump
(rotary vane pump)

- 10 -
LOCATE COMPONENTS

Control panel,1. see “INDICATOR LIGHTS AND
BUTTON”
Front cover2.

Filter container I3.
Filter container II4.
Printed Circuit Board (PCB)5.
Filter AIF (RFI, EMI)6.

Outlet, puried water7.
Reject water outlet8.
Inlet water connection9.
Contact for indicator lights10.
Power cord11.
Handle12.

CV-models only)
Hose for rinse13.
Outlet, puried water14.
3/2-way valve15.
Timer control16.

Driving wheel, motor17.
Driving belt18.
Driving wheel, pump19.
PRODUCT DESCRIPTION
Shaft, common, high pressure- & loop pump20.
Pump gable/housing21.
Inlet valve22.
Flush valve23.
Inlet pressure sensor24.
Conductivity sensor25.
Outlet pressure sensor26.
Pressure accumulator valve27.
Outlet, puried water, with check valve28.
Membrane pressure vessel29.
Pressure regulating valve30.
Overow protection31.
Capacitor, motor32.
Motor33.
aB
1 2 34
C
7 8
9
10
11
12
5
6
D
14
13
15
16
32
29 31
22
21 23
24 25 27
26 28
20
E
17 19
18
33
30

- 11 -
INLET WATER SYSTEM
The inlet hose is connected to the inlet valve (normally closed). When the
outlet pressure sensor  detects a low pressure (lower than the preset start pres-
sure), does the printed circuit board (PCB)  energize the inlet valve, and the
valve opens (and the motor starts). The inlet valve includes a screen lter, for a rst
coarse particle ltration.
The inlet water ows to the integrated prelters  that consist of two lter
cartridges, congured in
- serial ow (in most RO400-models) or
- parallell ow (in most RO600-models)
The purpose of the preltration is to protect the membrane , from mechanical and
chemical wearing. Better preltration gives longer service life of the membrane and
the product overall.
In serial ow does the preltration consist of one particle (sediment) lter and
one granulated activated carbon (GAC) lter . The particle lter removes par-
ticles larger than approx 10 µm. The carbon lter reduces Chlorine (Cl2), which is
important as the surface the membrane otherwise is damaged by Chlorine over time.
In parallell ow does the preltration consist of two identical carbon block lters
. The carbon block combines particle removal (larger than approx 5 µm) and
Chlorine reduction in one cartridge. The advantage of parallell ow is the lower
pressure drop, which becomes more important at high water ow (RO600 compared
with RO400). The ner particle ltration gives an improvement not only on the
membrane service life, but also the integrated high pressure pump .
3
1H
F
In the following, the letters/numbers within brackets refer to gure.
INDICATOR LIGHTS AND BUTTON
On the control panel of the water purier there are seven indicator lights (diods,
LEDs) and one push button, see g. F.
stop The product has stopped working. ‘stop’ alone or
with another diod gives an error code indicating the fault.
 Change prelter/s/.
Too low pressure at the inlet, caused by blocked lters/s/,
low water supply pressure e.g.
on/off Indicates that the product is switched on (power on).
 Change prelter/s/.
Filter/s/ consumed due to time in use.
 Low purication level.
 Good purication level.
 High purication level.
calibration button Push button to
- calibrate levels for purication level,
- reset timer function of ‘lter II’,
- enter varios modes and control
functions useful during service.
For more information about indications, see “TROUBLESHOOTING”.
Indicator lights
An accessorie, see g. G, aimed for products installed under kitchen sink when
control panel is not always visable. It is intended to be mounted below the drinking
water faucet and connected to the indicator contact on the product backside.
- Green light indicate ‘purication level II / III’.
- Red light indicate ‘purication level I’
PRODUCT DESCRIPTION
2
1. Particle lter
2. Granulated Activated
Carbon (GAC) lter
3. Carbon block lter
G
Indicator lights

- 12 -
PRODUCT DESCRIPTION
PUMP SYSTEM
After the water has passed the prelters, it passes through the high pressure pump
. The high pressure pump is a vane pump, belt  driven by a motor .
The pump is mounted in a special designed pump housing in brass. The
integration of several parts and components in the pump housing is the key to the
compact size of the product.
The high pressure pump increases the system pressure (pressure inside the mem-
brane pressure vessel , applied onto the membrane surface) up to a maximum
of approx. 15 bar. The system pressure can be measured according to g. I.
The system pressure is adjusted with the screw on top of the pressure regulation
valve. The position of the screw determines the tension of the spring loaded
piston against the system pressure. In case the system pressure exceeds the spring
load, will the valve act as a relief valve and lead back the water to the pump inlet.
The screw is adjusted to the correct position from the factory and should not be
changed unless the purpose is troubleshooting and the measures is fully under-
stood.
The regulation of the pressure is independant of inlet water pressure and tempera-
ture. Another feature is that the valve instantly reduces the system pressure, to
minimize the effect of water hammer, when a valve or faucet on the pure water hose
is closed.
MEMBRANE SYSTEM
Just before the pressurized water reach the membrane vessel it passes through the
loop pump , positioned on the same shaft as the high pressure pump. The loop
pump increases the ow rate across the membrane surface (cross-ow) by internal
recirculation. This is the key for the high performance: high water efciency (recov-
ery), high capacity and high purication efciency, still with good resistance against
scaling.
(For better understanding; there is a balance between good water efciency and the
risk to clog the membrane.)
Inside the membrane pressure vessel, the water reaches the Reverse osmosis (RO)
membrane element, see g. . The type is spiral wound Thin Film Composite (TFC)
membrane.
Inside the membrane element the water can take three ways:
A certain proportion of the water passes through the membrane (or more accurate,
the membrane at sheet). The quantity depends on system pressure, temperature,
water quality and general performance of the membrane.
Another proportion of the water passes through the ush valve  to the reject
water hose, routing the reject water to drain. The quantity of water ushed to drain
(during operation) is xed, and determined by a ow restrictor (small hole)  in
the ush valve and the system pressure. The size of the hole depends on model.
Most of the water does however just cross the membrane surface into the loop pump
again, and recirculates.
I
K
Position for pressure gauge.
Adapter 1/8” thread.
Gauge should go up to 25 bar.
Membrane element.
Below opened to
show the membrane
components.
J
Flow restriction
If the screw of the pressure regulating valve is adjusted, do not forget to
.
CAUTION
!

- 13 -
PRODUCT DESCRIPTION
PURIFIED WATER SYSTEM
After the puried water leave the membrane pressure vessel, it pass through the
pressure regulating valve . This is a safety feature, to avoid high pressure to
the distribution net in case of failure, and to protect the the product from water ham-
mer when a valve or faucet is closed on the pure water hose.
Before the puried water outlet  the pure water passes a conductivity sensor
, described under “WATER QUALITY MONITORING”, a check valve 
(integrated in the puried water outlet) and pressure accumulator valve . The
check valve prevents back ow to the product. The pressure accumulator valve
buffers a small quantity of water to compensate for small internal or external leak-
ages and has also a reducing effect of water hammer.
Attached to the pressure accumulator valve is the outlet pressure sensor . The
outlet pressure sensor measures the pressure in the puried water outlet, and gives a
signal to the electronics to start and stop the product.
The pressure drops if a valve or faucet opens or if a connected tank needs lling;
and the pressure increase when a valve or faucet closes or if a connected tank is
lled up.
Low pressure starts the product, described under “INLET WATER SYSTEM”.
High pressure stops the product, but before closing the inlet valve and the motor, is
a ushing performed, described under “FLUSH SYSTEM”.
See Table 1 for values.
FLUSH SYSTEM
The purpose of ushing is to ll up the system, exchange old water inside the prod-
uct or ush out an increased concentration of contaminants after a production cycle.
With the motor running and inlet valve open, is the ush valve energized to open
completely. Reject ow goes from approx 2 / 2.5 litres/minute to more than 6 l/
minute.
The ushing takes place in four different situations:
When the product is connected to electrical supply, does the product ush 30 a)
seconds. This is done to ll up the system when a product is new or to manu-
ally efciently replace the water inside the unit.
This ush cannot be interrupted by production of puried water.
The product ush approx. every 12 hours (starting when the product is con-b)
nected to electrical supply), for 30 seconds, in order to replace the water
inside. This is done to avoid biological growth. Therefore is it important that
the product is connected to electrical and water supplies.
This ush is interrupted if puried water is required.
After every production cycle does the product ush the system, to ush out c)
an increased concentration of contaminants. The ushing time is relative to
the time the product was in operation. As indication should ush be about 20
seconds after 2 minutes operation. Maximum ush time is 90 seconds.
This ush is interrupted if puried water is required.
Only applicable to commercial (C-) models:d)
When operation cycles are long, does the product make an automatic ush
for two minutes every 15 minutes operation, i.e. 15 - 2 - 15 - 2 ... The reason
is the same as for point c) above.
This ush cannot be interrupted by production of puried water.
MODEL
PRESSURE
(bar)
RO400A
RO400B-models
C-models
Start level 0.5 0.5 3
Stop level 4.5 2 4.5
Table 1.

- 14 -
WATER QUALITY MONITORING
Puried water quality is monitored continously with a conductivity sensor 
positioned in the water ow just before the puried water outlet.
Conductivity is the measure of the ability for a material to conduct electricity, in
this case in water. With a high concentration of ions in the water will the conductiv-
ity be high, and vice versa.
Ions are salts or minerals, for example Sodium, Iron, Lead, Chloride, Sulphate, dis-
solved in water. Conductivity is measured in mS/m (milliSiemens/meter) or µS/cm.
The alternative is to indicate concentration of salts, measured in mg/l or ppm (parts
per million). The term TDS (Total Dissolved Solids) is often used and it is the same
as salt content.
During production of puried water is the measured value compared with a preset
value determined at installation. The current purication level is displayed on the
control panel .
Ions are much smaller than most other possible contaminants in the inlet water. The
conclusion is if ions are separated, are also heavy metals, organics etc also reduced
with the same or better efciency.
There are exceptions to this rule. The rejection efciency through the membrane
depends on the substance size (molecular weight), shape (on molecular/ion level)
and electrical charge. The larger and bulkier the substance is, and with electrical
charge, the better is the rejection rate. Examples of exceptions are gasses dissolved
in water, and small organical molecules (THM’s e.g.). These have a rejection of
>60% compared with >95% for ions in general.
When the membrane is in the beginning of break-through, will the smallest ions
pass rst: Sodium and Chloride. In most waters are these the highest concentrated.

- 15 -
LOW PRESSURE RESTART
This function is included only in commercial (C-) models.
In commercial applications it is common that the water purier operates automati-
cally towards a connected external equipment. An alarm stop may cause troubles
before it is noticed by the user.
The reason for the alarm is sometimes a temporary pressure drop in the inlet water
pressure. Examples could be roadwork, momentaneous high water consumption
near the the installation, mistake by a co-worker to close the water supply etc.
The purpose of this function is to avoid these unnecessary alarms, and allow the
product to automatically restart after an alarm from low inlet pressure.
The water purier will make three attempts to restart: After 3 minutes, 20 minutes
and nally 4 hours. If the pressure is not sufcient after three attempts the water
purier stop permanentely.


not help.
INDICATION FAULT CASE REMEDIAL ACTION
Only included in commercial (C-)
models.
The product has stopped due to low
inlet pressure detected by the inlet
pressure sensor.
The system is idle waiting for auto-
matic restart.
Attend the problem according to the
“TROUBLESHOOTING” guide.
Press and hold the ‘calibration’ but-
ton until the warning lights goes out,
and the product will restart.
Diods for ‘lter I’ and ‘stop’ blinks alternately.
Slow ‘lter I’
Quick ‘stop’
Awaiting 1st restart
(after 3 minutes)
Medium ‘lter I’
Medium ‘stop’
Awaiting 2nd restart
(after further 20 minutes)
Quick ‘lter I’
Slow ‘stop’
Awaiting 3rd and last restart
(after further 4 hours)
Low pressure stop (same indication
for all models).
In commercial (C-) models this
means that the product has made
three unsuccessful restart attempts.
PRODUCT DESCRIPTION
-


be removed when the product is
idle in restart mode.
CAUTION

- 16 -
DISPLAY NUMBER OF LOW PRESSURE STOPS
The number the water purier stops due to low inlet pressure is
counted by the water purier.
Any low pressure stop increase the risk for pump damages and
should be avoided, and this function is a help in this work.
Follow the instructions for1. “DISPLAY TIME IN OP-
ERATION”, point 1-6.
When all three diods for ‘purication level’ are 2.
lightened, to conrm that timer display function is
completed, click ‘calibration’ button.
Count the blinks of ‘lter I’ diod.3.
(35 blinks indicate 35 low pressure stops.
Maximum displayed is 255. )

supply and connect again.
When the total number of low pressure stops have4.
been displayed, the diod for ‘stop’ lights up for a
second and goes out.
Display of low pressure stops is completed.


change.
Connect the water purier to electrical and water 1.
supplies. The product starts ushing (30 seconds)
and then stops.
With the product in standby, press and hold the ‘cali-2.
bration’ button throughout points a) and b) which
takes totally 14 seconds:
diod for ‘lter II’ lights up and goes out (8 sec)a)
diod for ‘lter II’ lights up and goes out (6 sec)b)
Release the button.3.
-
sure stops is now set to zero.
RESET FAULT INDICATION
To avoid the necessity of unplugging the water purier to over-
ride an alarm stop, a reset function is included.
This function can be used for all possible faults.

When the product is in alarm state, press and hold1.
the ‘calibration’ button until the warning lights go
out.
Release the button, and the product will restart with2.
normal ushing (30 seconds).
When a reset is made to over-ride a low pressure restart at-
tempt, will the product start to produce water immediately,
without ushing.
DISPLAY TIME IN OPERATION
The water purier is equipped with a counter for measuring
the total time of water production.
This is a valuable function, for example to estimate time to
next service.
Connect the water purier to electrical and water 1.
supplies. The product starts ushing (30 seconds)
and then stops.
With the product in standby, press ‘calibration’ but-2.
ton for approx 3-4 seconds and then release.
If the button is pressed too long the timer for

Immediately, press ‘calibration’ button and hold 3.
until all three diods for ‘purication level’ lights up.
Release the button. The timer display starts.4.
Count the blinks of ‘purication level I/II/III’ diods 5.
(see details below).
When the total number of hours have been dis-6.
played all three diods light up and stay on.
(If there is no blinks before all 3 diods lights up, the
total number of hours is less than 10 hours)
Timer display function is completed.7.
This is the starting point for next function, see
“DISPLAY NUMBER OF LOW PRESSURE STOPS”.

The timer displays 1000 hours, 100 hours and 10 hours by
blinking the ‘purication level’ diods in sequence.
Example: A total operation time of 1044 hours will be dis-
played with:
1 blink ‘purication level I’TDS LED 1
0 blink ‘purication level II’
4 blinks ‘purication level III’
The last digit (4 hours) will not be displayed.
Time in operation (hours)
1000 h 100 h 10 h 1h
1040
It is not possible to reset the counter for time in
operation.
PRODUCT DESCRIPTION

- 17 -
SERVICE RECORDS
DATA COLLECTION AT INSTALLATION
Recommended data to be collected at installation:
Customer name / address: Purchase date:
SKU no.:
91073002 -
Product no.:
919240 -
Serial no.: Installation date:
Remarks on inlet water quality: Inlet water temperture (ºC): Inlet owing pressure (bar):
Remarks on installation conditions: Pretreatment: Inlet water cond. (mS/m):
Puried water cond. (mS/m):
(after 5 minutes
operation)
Reject water cond. (mS/m):
(after 5 minutes
operation)
Pure water capacity (l/minute): Reject water ow (l/minute)
System pressure (bar): Comments:
Customer ..
.. has been informed on how to use the product Yes / No
.. has been informed about regular maintenance Yes / No
.. knows where to nd consumables Yes / No
.. has got the user manual supplied with the product Yes / No
Signature customer: Signature installer:
DATA COLLECTION AT SERVICE
Recommended data to be collected at any service. Data will facilitate analysis and allow the performance development to be
followed. This makes it easier to determine preventive service.
Customer name / address: Date of service call and customer claim:
SKU no.:
91073002 -
Product no.:
919240 -
Serial no.: Installation date:
Inlet water temperture (ºC): Inlet owing pressure (bar): Inlet water cond. (mS/m): System pressure (bar):
Puried water cond. (mS/m):
(after 5 minutes
operation)
Reject water cond. (mS/m):
(after 5 minutes
operation)
Pure water capacity (l/minute): Reject water ow (l/minute):
General condition of the product, water quality and installation: Time in operation (hours)
1000 h 100 h 10 h 1h
0
Service action: Parts changed:
Article no: Article description:
Date: Service / repair completed:
Yes / No
Next visit: Signature service technician:

- 18 -
TROUBLESHOOTING
guide compromises the internal safety systems of the product
and may also involve operation of the water purier without
protective cover.





The “1) LED INFORMATION GUIDE” will help you to inter-
pret the LED information shown on the product’s display.
The “2) FAULT IDENTIFICATION GUIDE” offers additional
information such descriptions of a number of symptoms,
e.g. low ow, and suitable solutions.

If a fault can be identied based on the LED-information, it is
advisable to see the “FAULT IDENTIFICATION GUIDE” which
offers more extensive information about the symptoms as well
as suitable solutions and actions to take.
If a faulty component is identied, replace the component
referring to the step-by-step instructions in this manual, see
“SERVICE”. In addition, please consult the user’s manual for
the product and its “TROUBLESHOOTING” section for further
information.
Please note that some of the methods in this troubleshooting
CAUTION
!
To protect the user and the water purier from incorrect use, there are several different built-in alarms, which cause the purier to
give an indication and stop. The table below gives probable causes of warnings given by the water purier.
The lights can appear in the following three ways: extinguished lit ashing
INDICATION FAULT CASE REMEDIAL ACTION
Time to replace lter or clean the grid.
The feed water’s pressure is too low.
There is time before the water purier experi-•
ences an emergency stop. Prepare to replace
lter I and to clean the grid.
Check the feed pressure. If necessary, increase•
the pressure.
The feed pressure is too low so the water
system has stopped. The system is idle
waiting for restart.
The system will attempt to restart automatically.•
Make sure that the feed pressure is sufcient. If
necessary, change lters.
If the calibration button is pressed, the system•
will restart. Release the button as soon as the
Filter I and Alarm light goes out.
Alarm for blocked lter I or II.
Alarm for dirt in the grid.
Alarm for water leak/condensation on the base
plate under the pre-lters.
The feed water’s pressure is too low.
Check that there is nothing in the lter contain-•
ers that is obstructing the water ow.
If necessary, replace lter I or II.•
Check the grid according to• CLEANING THE
GRID.
Check that all the connections are watertight.•
If there is water on the base plate, lean the prod-•
uct forward and wipe it up.
A pressure increase pump for the feed water can•
alleviate this.
Check the parts that can affect the feed water’s •
pressure (water line, coarse lter, extra pre-l-
ter).
LED INFORMATION GUIDE

- 19 -
TROUBLESHOOTING
INDICATION FAULT CASE REMEDIAL ACTION
Warning about used lter. Change lter II in accordance with • REPLACING
THE FILTERS.
See “• FAULT IDENTIFICATION TABLE”, section 9.
Alarm for poorer water quality. If the water purier is new and not yet calibrat-•
ed, rectify according to the section CALIBRA-
TION.
Pull out and reconnect the plug so that the water•
purier ushes. Repeat this procedure two or
more times.
See “• FAULT IDENTIFICATION TABLE”, section 6.
Alarm indicating that calibration has been
commenced, but not carried out correctly
(probably due to the tap having been closed
before 10 minutes had elapsed).
Restart the water purier by pulling out and •
reconnecting the plug so that ushing is per-
formed. Recalibrate the water purier according
to the section CALIBRATION.
See “• FAULT IDENTIFICATION TABLE”, section 4.
Alarm for fault in the water quality meter.
Restart the water purier by pulling out and •
reconnecting the plug so that ushing is per-
formed. Wait for 2 hours then use the water
purier as normal.
See “• FAULT IDENTIFICATION TABLE”, section 4.
Warning that the tap has been on for more than
15 minutes without a pause, and that the prod-
uct has shut down automatically as a result.
Turn off the tap and leave the water purier •
undisturbed for at least 30 minutes.
Restart the product by disconnecting and then•
reconnecting the electricity.
After automatic ushing the water purier will •
be ready for use again.
See “• FAULT IDENTIFICATION TABLE”, section 4.
 The membrane may have become blocked. Clean the water purier in accordance with •
“CLEANING/DESCALING”.


The water pressure between the water purier
and e.g. tap, valve or tank has dropped below
the water purier’s starting pressure level.
Check the connections.•
Check that the ends of the water puried water •
hose are at, circular and with no burrs.
Check that taps and valves are watertight in their•
closed position.
Unpleasant odour When the water purier is stationary (without
power supply) and there is microbiological
growth in the water, the water can smell “bad”.
Try ushing the water purier according to the •
section FLUSHING.
Clean the water purier in accordance with •
DISINFECTION.
If the water purier has experienced an emergency stop: Restart by pulling out the plug, wait for at least one minute and then,
reconnect the plug again.

- 20 -
TROUBLESHOOTING
FAULT IDENTIFICATION GUIDE
This guide describes:
A number of symptoms as well as feasible solutions to these.•
Special features regarding some of the symptoms. These notes, e.g. Low inlet water temperature• 1,
are listed in the “Comments” section following the “Fault identication table”.
Possible error codes on the product’s display. However, depending on what is causing the problem, symptoms can appear •
without error codes.
The following subjects are addressed in the following “Fault identication table”:
Broken diods on the printed circuit board1.
Low water ow2.
The water purier does not stop even if the valve/faucet is closed3.
The water purier does not start/does not start to produce water.4.
Filter I, stop or warning. Low pressure warning. (Possible internal leakage.)5.
Low water quality, warning/stop.6.
Intermittent start and stop.7.
Broken PCB.8.
Delayed start of motor.9.
Non normal sound10.
FAULT IDENTIFICATION TABLE
Symptom Possible error
codes Check/Action Remedy
 When suspecting an error•
code, perform a diode test
to verify that the code is
correct.
A broken diod can result in an erroneous in-
terpretation of error codes. Replace the printed
circuit board (PCB).

Low inlet water
temperature1
Membrane may be
clogged2
<Not displayed>
Measure the inlet water tem-•
perature and then, compare
it with the specication at
15° C.
Has the product been des-•
caled recently or is the inlet
water soft?
Has the product been off-•
line without preservation for
an extended period of time?
Estimate the ow variation due to temperature
variation. If this can explain the low ow,
a descaling may increase the ow rate. If a
service technician is present, proceed with the
system pressure measurement.
If there is reason to believe that the product
has not been descaled - descaling is recom-
mended.
If the product has been off-line without pres-
ervation - proceed with a disinfection. Then,
if a service technician is present, proceed with
system pressure measurements.
a)
b)