Flexiheat SFKA 28/150 User manual

SFKA 28 /150 - RAD - ING - Manuale - 2102.1_SKM1_firm.L225B
Installation, Use
and Maintenance Manual
for model
0476
SFKA 28 /150
Condensing water heater
with accumulation

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SFKA 28 /150 - RAD - ING - Manuale - 2102.1_SKM1_firm.L225B
SFKA 28.150_EN
SUMMARY
SUMMARY
INTRODUCTION 4
1. INSTALLER SECTION 7
1.1. INSTALLATION 8
1.1.1. GENERAL INSTALLATION WARNINGS 8
1.1.2. WATER HEATER LOCATION ENVIRONMENTAL REQUIREMENTS 8
1.1.3. REFERENCE LEGISLATION 9
1.1.4. UNPACKING 10
1.1.5. MINIMAL TECHNICAL SPACES 11
1.1.6. OVERALL DIMENSIONS 12
1.1.7. JIG 12
1.1.8. RECIRCULATION MODE CIRCULATOR PREVALENCE/FLOW DIAGRAM 13
1.1.9. HYDRAULIC CONNECTION 14
1.1.10. RECIRCULATION MODE 15
1.1.11. FILLING THE CONDENSATE COLLECTION SIPHON 16
1.1.12. ANTI-FREEZE PROTECTION 17
1.1.13. GAS CONNECTION 18
1.1.14. ELECTRICAL CONNECTION 18
1.1.15. POWER SUPPLY 19
1.1.16. OPTIONAL ELECTRICAL CONNECTIONS 20
1.1.17. FUME EXHAUST FITTINGS 22
1.1.18. INSTALLATION MODES 23
1.1.19. TYPES OF FUME EXHAUST SYSTEMS 25
2. SUPPORT CENTER SECTION 29
2.1. FIRST START-UP 30
2.1.1. PRELIMINARY OPERATIONS FOR FIRST START-UP 30
2.1.2. WATER HEATER COMMISSIONING 31
2.1.3. CO2 VALUE CHECK AND CALIBRATION 32
2.1.4. ACCESSING AND PROGRAMMING THE PARAMETERS 33
2.1.5. DIGITECH CS PARAMETERS TABLE 35
2.1.6. ELECTRIC FAN FREQUENCY/HEAT CAPACITY DIAGRAM 41
2.2. MAINTENANCE 42
2.2.7. GENERAL MAINTENANCE WARNINGS 42
2.2.8. TECHNICAL DATA 43
2.2.9. TECHNICAL ASSEMBLY 46
2.2.10. HYDRAULIC BOARD 47
2.2.11. WIRING DIAGRAM 48
2.2.12. ACCESSING THE WATER HEATERS 49

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SFKA 28.150_EN
SUMMARY
2.2.13. ACCESSING THE ELECTRONIC BOARD 50
2.2.14. EMPTYING THE DOMESTIC SYSTEM 51
2.2.15. STORAGE TANK MAINTENANCE 52
2.2.16. FAULT SIGNALLING CODES 53
2.2.17. ACTIVE FUNCTIONS SIGNALLING CODES 58
2.2.18. GAS TYPE TRANSFORMATION 59
3. USER SECTION 61
3.1. USE 62
3.1.1. GENERAL USE WARNINGS 62
3.1.2. CONTROL PANEL 63
3.1.3. DISPLAY ICONS 64
3.1.4. INFO MENU DISPLAY DATA 65
3.1.5. START-UP 66
3.1.6. OPERATING MODE 66
3.1.7. INFORMATIONAL NOTE ON ANTI-FREEZE FUNCTION 66
3.1.8. FAULT SIGNALLING CODES 67
3.1.9. ACTIVE FUNCTIONS SIGNALLING CODES 69
3.1.10. FAST H2O FUNCTION 69
3.1.11. MAINTENANCE 70
3.1.12. COVER CLEANING 70
3.1.13. DISPOSAL 70

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2.
INTRODUCTION
WARNING
Before starting any operation it is mandatory to
read this instruction manual, in relation to the
activities to be carried out as described in each
relevant section. Proper operation and optimal
performance of the water heater are ensured by
strict compliance with all the instructions given in
this manual.
The installation, use and maintenance manual is
an integral and essential part of the product and
must be delivered to the user.
MANUAL USERS
The manual users are all those who install, use
and maintain the water heater.
The water heater must be used and accessed
only by qualified operators that fully read and
understood the use and maintenance manual,
paying particular attention to the warnings.
READING AND SYMBOLS OF THE MANUAL
To ease the understanding of this manual,
recurrent symbols where used, in particular:
› On the outer margin of the page is placed a
thumb index indicating the type of user to which
the instructions in that section address.
› The titles are differentiated by thickness and
size in accordance with their hierarchy.
› The images contain important parts described
in the text, marked with numbers or letters.
› (See chap. “chapter name”): this entry indicates
another section in the Manual that you should
refer to.
› Device: this term is used referring to the water
heater.
DANGER
It identifies an information related to a
general danger that if not complied with, may cause
serious personal damage or even death.
ATTENTION
It identifies an information that if not
complied with may cause small or medium level
lesions to the person or serious deterioration to the
water heater.
WARNING
It identifies a precaution information that
must be observed in order to avoid damaging the
machine or parts of it.
MANUAL STORAGE
The manual must be carefully stored and replaced
in case of deterioration and/or low legibility.
If you misplace the use and maintenance manual,
you can request it from the Service Centre giving
the serial number and model of the boiler indicated
on the data plate placed on the right side of its
casing.
INTRODUCTION

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2 .
MANUFACTURER WARRANTY AND
RESPONSIBILITY
The technical and functional features of the device
are ensured by its use in compliance:
1. with the use and maintenance instructions
contained in the manuals accompanying the
product, the content of which the customer
certifies that he is aware;
2. with the conditions and purposes to which
devices of the same type are intended.
For more information on the warranty validity,
its duration, the obligations and the exemptions,
please consult the First start-up certificate
attached to this manual.
The manufacturer reserves:
› the right to modify the tools and relative
technical documentation without any obligation
to third parties; neither will the company be
held responsible for any inaccuracies in this
handbook deriving from printing or translation
errors;
› the material and intellectual ownership of
this manual and forbids its distribution and
duplication, even partial, without prior written
authorization.
PRODUCT CONFORMITY
The materials used such as copper, brass,
stainless steel create a homogeneous, compact
and functional assembly, easy to install and
manage. In its simplicity, the water heater is
equipped with all accessories necessary to render
it a veritable independent heating unit. All water
heaters are tested and delivered with a quality
certificate signed by the tester.
INTRODUCTION

The installation operations described in this section, must
be performed only by qualified personnel, having the
appropriate technical training in the field for the installation
and maintenance of components of civil and industrial
domestic hot water production and heating plants.
1. INSTALLER SECTION1. INSTALLER SECTION

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1. INSTALLATION
INSTALLER
1.1. INSTALLATION
1.1.1. GENERAL INSTALLATION
WARNINGS
ATTENTION
This water heater may be used only for the
purpose for which it has been designed: heat water
to a temperature below boiling point at atmospheric
pressure. Any other use is considered wrong and
dangerous. The manufacturer is excluded from any
contractual or extra-contractual responsibility for
damages caused to people, animals or property due
to errors during installation.
ATTENTION
This water heater must be installed
only by qualified personnel, having the appropriate
technical training in the field for the installation and
maintenance of components of civil and industrial
domestic hot water production and heating plants.
ATTENTION
After having removed the packing, make
sure the device is intact. In case of doubt, do not use
the device and contact the supplier.
BEFORE INSTALLING THE WATER HEATER,
THE INSTALLER MUST MAKE SURE THAT THE
FOLLOWING CONDITIONS ARE MET:
› The device is connected to a heating system
and a water supply network appropriate for its
power and performance.
› The location must be properly vented through
an air vent.
› The air vent must be placed at floor level to
prevent it from being obstructed, protected by
a grid that does not hamper the useful passage
section.
› The device is suitable for use with the type of
gas available by checking the water heater
data plate (placed on the inner side of the front
casing).
› Make sure that the pipes and joints are perfectly
sealed, without any gas leaks.
› Make sure that the grounding system works
properly.
› Make sure that the electrical system is suitable
for the maximum power absorbed by the device,
value indicated on the data plate.
1.1.2. WATER HEATER LOCATION
ENVIRONMENTAL
REQUIREMENTS
The device installation location should be vented
due to the presence of threaded joints on the
gas supply line. The location should be therefore
provided with vents as to ensure air exchange,
with output grid in the natural accumulation area
of potential gas losses.
WARNING
DO NOT install the water heater in a
technical compartment near a swimming pool or a
laundry, to avoid that the combustion air is exposed
to chlorine, ammonia or alkaline agents that may
worsen the corrosion phenomenon of the heat
exchanger. Failure to observe this caution will void
the warranty of the heat exchanger.

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1. INSTALLATION
INSTALLER
WARNING
If the temperature in the appliance
installation location goes below -10 centigrades,
please fill the plant with anti-freeze liquid and insert
and a frost prtotection kit (see chapter ‘ANTI-FREEZE
PROTECTION’).
WARNING
The manufacturer will not be held
responsible for damages caused by incorrect
installation not in conformity with the above
mentioned instructions and not duly protected from
freeze.
1.1.3. REFERENCE LEGISLATION
The installation must be done according to
the requirements of current legislation and in
compliance with local technical regulations,
according to the indications of the good technique.

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1. INSTALLATION
INSTALLER
1.1.4. UNPACKING
WARNING
Please unpack the boiler just before
installing it. The Company is not responsible for
the damages caused to the device due to incorrect
storage.
WARNING
The packing elements (cardboard box,
wooden crate, nails, fasteners, plastic bags, expanded
polystyrene, etc.) must be kept out of the reach of
children as they may be dangerous. Therefore they
should be dismantled suitably differentiating them in
accordance with the standards in force.
To unpack the water heater, proceed as follows:
› cut the fixing strip (see A-fig.1);
› remove the cardboard box lifting it upwards
(see B-fig.1);
› push the water heater on one side and remove
the pallet underneath (see C-fig.1).
AB C
fig. 1

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1. INSTALLATION
INSTALLER
1.1.5. MINIMAL TECHNICAL SPACES
The appliance must be installed exclusively on a
flat horizontal solid floor capable of supporting its
weight.
In order to allow the access inside the water heater
for maintenance operations, you have to respect
the minimum technical spaces indicated in figure
1.
H
A
Y
X
A - 500 mm
X - 250 mm
Y - 250 mm
H - 300 mm
fig.1

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1. INSTALLATION
INSTALLER
1.1.6. OVERALL DIMENSIONS
1.1.7. JIG
1530
570
600
320
200
134 82
C
F
RC
G
162
68.5
68.5
68.5
82
G- GAS Ø 3/4
C - HOT Ø 3/4
F- COLD Ø 3/4
RC- RECIRCULATION OPTIONAL

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1Diagrammaportata-prevalenzacircolatore_SFKA28.150_EN
1. INSTALLATION
INSTALLER
1.1.8. RECIRCULATION MODE CIRCULATOR PREVALENCE/FLOW DIAGRAM
III Circulator priority maximum speed
II Circulator head at second speed
ICirculator head at minimum speed
Appliance Loss
6
0
1
2
3
4
5
0 0.5 1 1.5 2 2.5
ZRS 12/6
III
II
I
PREVALENCE (m)
FLOW RATE (m3/h)
6
0
1
2
3
4
5
0 0.5 1 1.5 2 2.5

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1. INSTALLATION
INSTALLER
1.1.9. HYDRAULIC CONNECTION
DANGER
Make sure that the tubes of the water and
heating plant are not used as grounding system for
the electrical plant. There are not suitable for such
use.
WARNING
To prevent voiding the warranty and to
ensure the proper operation of the water heater,
please wash the plant (if possible when hot) with
suitable pickling or descaling solutions in order
to remove the impurities coming from tubes and
radiators.
WARNING
If the water heater is installed in a
hydrostatic position lower than those of the user
devices (radiators, fan coils, etc.), mount the shut-off
valves on the domestic water heating circuit to ease
the performance of the maintenance operations if it
is necessary only to empty the water heater.
WARNING
When connecting the equipment to
water supply, avoid excessive bending and recovery
operations from any off axis positioning that may
damage the tubes causing leaks, malfunction or
early wear.
WARNING
In order to avoid any vibrations and noises,
do not use tubes with small diameters or elbows with
small radius and significant cut-off of the passage
sections.
WARNING
Connect the water heater safety drains
to a discharge funnel. The manufacturer is not
responsible for any floods due to safety valve opening
in case of plant overpressure.
In order to prevent limestone build-up and
damages to the domestic water heat exchanger,
the hardness of the domestic supply water
should not exceed 15 °f. However, please check
the characteristics of the water used and install
suitable treating devices.
The heat exchanger coil cleaning frequency
depends on the hardness of the supply water and on
the presence of solid residues or impurities inside
the water that are often present in case of recently
installed plants. Based on the characteristics of
the infeed water, you should install suitable water
treating devices, for residues presence please
install a line filter.
The pressure of the cold infeed water should be
between 0.5 and 6 bar. In case of greater pressure
values, please install a pressure reducer upstream
from the water heater.

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1 Ricircolo_scaldabagno_SFKA_EN
1. INSTALLATION
INSTALLER
1.1.10. RECIRCULATION MODE
The water heater can manage a recirculation
system which is aimed to provide a better well-
being for the domestic hot water needs, thus
delivering immediately a large amount of hot water.
To activate the recirculation mode, please proceed
as follows:
› Install the optional recirculation kit (COD: 65-
00918), electrically connect the pump and the
recirculation sensor, as specified in the chapter
‘OPTIONAL ELECTRICAL CONNECTIONS’.
› activate the recirculation mode by pressing
simultaneously the ‘ ’ and ‘ ’ buttons of
the control panel (fig. 1). The activation of the
recirculation mode is displayed onto the control
panel by means of the ‘rc’ symbol.
› adjust the setting of the return temperature by
pressing ‘ ’ and ‘ ’ (fig. 2). The activation of
the pump is displayed onto the control panel by
means of the pump ‘ ’ symbol.
To detect the return temperature, the system
activates the pump for 20 seconds every 10
minutes.
If the temperature detected therein, by the
recirculation sensor, is lower than the required
one, the pump activates and the appliance operates
at the minimum fire rating.
When the required temperature is achieved, the
appliance shuts-off and the pump runs for 40
seconds(thislattervaluecanbeadjustedbymeansof
parameter P04). The highest possible temperature
of the hot water, during the recirculation mode, is
of 53 °C.
fig. 2
fig. 3

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1. INSTALLATION
INSTALLER
1.1.11. FILLING THE CONDENSATE
COLLECTION SIPHON
Before starting the water heater you have to fill the
condensate collection siphon in order to avoid fuel
reflux through the siphon.
Fill the condensate collection siphon as follows
(see fig. 1):
› Unscrew the “T” cap from the siphon, fill three
quarters of the the siphon with water and screw
the “T” cap back in;
› Connect the dedicated flexible condensate
draining tube “P” to a waste disposal system.
The condensate can be drained directly in
the sewerage system by inserting an easily
serviceable siphon.
P
T
fig. 1

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1. INSTALLATION
INSTALLER
1.1.12. ANTI-FREEZE PROTECTION
The water heater is protected against freezing
thanks to the electronic board preparation with
functions that start the burner and heat the
concerned parts when their temperature goes
below the minimum pre-set values, protecting
the water heater up to an external temperature of
-10°C.
The device starts when the hot water temperature
goes below 5 °C, automatically starting the burner
until the water reaches the temperature of 15 °C.
The system starts even if on the display appears
“OFF”, as long as the water heater is connected to
the power (230 V) and gas supply.
For long periods of standby, please empty the
water heater.
If the temperature goes below -10 °C please insert
electrical resistances kit (cod. 82259LP).

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1. INSTALLATION
INSTALLER
1.1.13. GAS CONNECTION
DANGER
In order to connect the gas connector of
the water heater to the supply pipe use a stop seal of
an appropriate size and material. The use of hemp,
teflon tape or similar materials is strictly forbidden.
BEFORE PERFORMING THE GAS CONNECTION,
MAKE SURE THAT:
› the gas adduction line complies with the
standards and regulations in force;
› the tubing's section suits the requested capacity
and its length;
› the tubing is equipped with all safety and control
devices required by the standards in force;
› the internal and external seals of the gas infeed
plant are checked;
› the device is suitable for use with the type of
gas available by checking the water heater
data plate (placed on the inner side of the front
casing. If they do not match you must take
the necessary measures to adapt the water
heater to another type of gas (see chapter GAS
TRANSFORMATION);
› the gas supply pressure falls within the values
indicated on the data plate.
1.1.14. ELECTRICAL CONNECTION
DANGER
The equipment is electrically safe only
if it is properly connected to an efficient grounding
system, performed in compliance with the safety
standards in force. You should check this essential
safety requirement. If in doubt, request an accurate
check of the electrical system performed by qualified
staff, as the manufacturer is not responsible for any
damages caused by lack of grounding system.
› Make sure that the electrical systems is
suitable for the maximum power absorbed by
the equipment, value indicated on the data plate.
› make sure that the cables section is appropriate
for the maximum power absorbed by the
equipment and that it is however not lower than
1 mm2.
› The equipment works with alternating current
of 230 V and 50 Hz. The electrical connection
must be performed using an all-pole switch with
an opening of at least 3 millimetres between
contacts placed upstream from the device.
WARNING
Make sure that the phase and neutral
cables connection is performed in compliance with
the wiring diagram (see chapter POWER SUPPLY).
WARNING
It is strictly forbidden the use of adaptors,
multiple plugs and/or extensions for the general
power supply of the equipment from the electrical
network.

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1 Alimentazione elettrica_SFK_EN
1. INSTALLATION
INSTALLER
1.1.15. POWER SUPPLY
To power the water heater connect the electrical
cables to the terminal inside the control panel as
follows:
DANGER
Cut off the voltage from the main switch.
› remove the water heater's front casing (refer to
chapter ACCESSING THE WATER HEATER).
› loosen the two screws and remove the plate “A”
(see fig. 1).
› after removing the plate, connect the electrical
cables to terminal “B” (see fig. 1):
· the yellow/green cable to the terminal marked
with grounding symbol “ ”.
· the blue cable to the terminal marked with
“N”.
· the brown cable to the terminal marked with
“L”.
After performing these operations, remount plate
“A” and the front casing.
LN
A
RcRc
B
BLUE
YELLOW/GREEN
BROWN
fig. 1

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1. INSTALLATION
INSTALLER
1.1.16. OPTIONAL ELECTRICAL
CONNECTIONS
The cables should be inserted inside the water
heater using the cable glands ‘P1’ and ‘P2’ placed
on the board (see fig. 1). Make a hole on the cable
gland, smaller than the cable diameter, to make
sure that the air cannot pass through.
To wire the optional below:
(TP) DOMESTIC HOT WATER PRE-HEATING
DEACTIVATION TIMER
use the terminal placed inside the control panel
as follows:
DANGER
Cut off the voltage from the main switch.
› remove the front casing of the water heater
(see chapter ACCESSING THE WATER HEATER);
unscrew the screws and remove plate “A” (see
fig. 2).
› After removing the plate, connect the electrical
cables to terminal “B” (see fig. 2);
› After performing these operations, remount
plate “A” and the front casing.
P2
P1
LN
A
RcRc
BTP
fig. 2
fig. 1