CALEFFI SATK20 Series Guide

1
SATK series compact wall-mounted heat interface unit
SATK20 series
INSTRUCTIONS FOR INSTALLATION, COMMISSIONING AND MAINTENANCE
CONTENTS
Safe y ins ruc ions
Dimensions
Technical specifica ions
Ins alla ion
Commissioning
Elec ronic regula or
SATK20103HE
SATK20203HE
SATK20303/SATK20403HE
SATK20305
Elec ric connec ions
Safe y and alarms
Troubleshoo ing
2
3
4
4
6
7
8
10
12
13
Main enance
14
Function
The SATK series heat interface unit allows independent control of heat
regulation and domestic hot water production within centralised heating
systems.
Product range
SATK20103HE Direct wall-mounted H U for LOW temperature
heating, instantaneous domestic hot water
production, power capacity 40 kW
SATK20203HE Direct wall-mounted H U for MED UM temperature
heating, instantaneous domestic hot water
production, power capacity 40 kW
SATK20303 Direct wall-mounted H U for H GH temperature
heating, instantaneous domestic hot water
production, power capacity 40 kW
SATK20403HE Direct wall-mounted H U for H GH temperature
heating, instantaneous domestic hot water
production, power capacity 40 kW. With pump on the
primary side.
SATK20305 Direct wall-mounted H U for H GH temperature
heating, instantaneous domestic hot water
production, power capacity 65 kW
78165.02 EN
www.caleffi.com
Commissioning checklis 16

2
WARNINGS
These instructions must be read and understood before installing and maintaining the device.
IMPORTANT! FAILURE TO FOLLOW THESE INSTRUCTIONS COULD RESULT IN A SAFETY HAZARD!
1 The device must be installed, commissioned and maintained by qualified technical personnel in accordance with national regulations and/or relevant local
requirements.
2 If the device is not installed, pre-run checked and maintained correctly in accordance with the instructions provided in this manual, it may not work properly and
may endanger the user.
3 Clean the pipes of any particles, rust, incrustations, limescale, welding slag and any other contaminants. The hydraulic circuit must be clean.
4 Make sure that all connection fittings are watertight.
5 When connecting water pipes, make sure that threaded connections are not mechanically overstressed. Over time this may result in breakage, causing water
damage and/or personal injury.
6 Water temperatures higher than 50°C may cause severe burns. When installing, commissioning and maintaining the device, take the necessary precautions so
that these temperatures will not be hazardous for people.
7 In the case of particularly hard or impure water, there must be suitable provision for filtering and treating the water before it enters the device, in accordance with
current legislation. Otherwise the device may be damaged and will not work properly.
8 Any use of the device other than its intended use is prohibited.
9 Any coupling of the device with other system components must be made while taking the operational characteristics of both units into consideration.
10 An incorrect coupling could compromise the operation of the device and/or system.
IMPORTANT: Risk of electric shock. Live parts. hut off the electric supply before opening the device box.
1 During installation and maintenance operations, always avoid direct contact with live or potentially hazardous parts.
2 The device must not be exposed to water drops or humidity, direct sunlight, the elements, heat sources or high intensity electromagnetic fields. This device cannot
be used in areas at risk of explosion or fire.
3 The device must be connected to an independent bipolar switch. If work has to be done on the device, cut off the electric supply first. Do not use devices with
automatic or time reset, or which may be reset accidentally.
4 Use suitable automatic protection devices in accordance with the electrical characteristics of the region where the device is installed and in compliance with current
legislation.
5 The device must always be earthed before it is connected to the electric supply. If the device has to be removed, always disconnect the earth connection after
disconnecting the electric supply conductors. Check that the earth connection has been made to the highest of standards under applicable legislation.
6 Electrical installation must only be carried out by a qualified technician, in accordance with legal requirements.
7 The device does not contain asbestos nor mercury.
LEAVE THIS MANUAL AS A REFERENCE GUIDE FOR THE USER. DISPOSE OF IN ACCORDANCE WITH LOCAL REGULATIONS. THE MANUFACTURER
RESERVES THE RIGHT TO CEASE PRODUCTION AT ANY TIME AND TO MAKE ANY CHANGES DEEMED USEFUL OR NECESSARY WITHOUT THE
OBLIGATION OF PRIOR NOTICE.
Key to symbols
SAFETY INSTRUCTIONS
Primary circuit flow
Primary circuit return
Domestic hot water outlet
Domestic cold water inlet
Low temperature circuit flow
Low temperature circuit return
Medium temperature circuit flow
Medium temperature circuit return
High temperature circuit flow
High temperature circuit return
NOTES:
1 Install water hammer arresters to compensate for any overpressure in the domestic water circuit;
2 In the presence of hot water recirculation or if a non-return valve is fitted into the domestic cold water inlet, provision must be made to accomodate the expansion
of the water contained within the system and the heat interface unit.
3 All hydraulic connections must be checked before pressurising the system. Vibration during transport may cause the connections to become loose. DO NOT APPLY
EXCE IVE TIGHTENING TORQUE otherwise the components may be damaged.
For the updated version of the technical documentation refer to www.caleffi.com

3
Dimensions
Medium: water
Maximum percentage of glycol: 30%
Maximum medium temperature: 85°C
Maximum working pressure: - primary circuit: 1 MPa (10 bar)
- domestic circuit: 1 MPa (10 bar)
Nominal DHW exchanger capacity: 40 kW
Maximum recommended primary circuit flow rate: 1,2 m3/h
Maximum DHW circuit flow rate: 18 l/min (0,3 l/s)
Minimum flow to activate domestic water flow meter: 2,7 l/min ±0,3
Maximum Dp on domestic water modulating valve: 90 kPa (0,9 bar)
Maximum Dp on mixing valve: 90 kPa (0,9 bar)
Electric supply: 230 V (ac) ±10% 50 Hz
Maximum power consumption: 80 W
20 W on SATK20303
Protection class: P 40
Pump (not present on SATK20303): UPM3 15-70
Pump by-pass pressure setting: 45 kPa (0.45 bar)
Actuators: stepper 24 V
Probes: NTC 10 kΩSafety thermostat (only on SATK20103HE): 55°C ±3
Materials
Components: brass EN 12165 CW617N
Fitting pipes: steel
Frame: RAL 9010 painted steel
Protective shell cover: EPP
Heat exchanger: brazed stainless steel
SATK20305 technical specifications
Medium: water
Maximum percentage of glycol: 30%
Maximum medium temperature: 85°C
Maximum working pressure: - primary circuit: 1 MPa (10 bar)
- domestic circuit: 1 MPa (10 bar)
Nominal DHW exchanger capacity: 65 kW
Maximum recommended primary circuit flow rate: 1,2 m3/h
Maximum DHW circuit flow rate: 27 l/min (0,45 l/s)
Minimum flow to activate domestic water flow meter: 2,7 l/min ±0,3
Maximum Dp on domestic water modulating valve: 90 kPa (0,9 bar)
Maximum Dp on mixing valve: 90 kPa (0,9 bar)
Electric supply: 230 V (ac) ±10% 50 Hz
Maximum power consumption: 20 W
Protection class: P 40
Actuators: stepper 24 V
Probes: NTC 10 kΩMaterials
Components: brass EN 12165 CW617N
Fitting pipes: steel
Frame: RAL 9010 painted steel
Protective shell cover: EPP
Heat exchanger: brazed stainless steel
SATK20305
SATK20103/203/303/403
10
450
65182,5
15490
550,5
49 65 101 65
265
430
10
450
65182,5
15490
550,5
49 65 207 65
430
A B C
3/4” M 1/2” M 3/4” F
SATK20103HE - SATK20203HE SATK20303
SATK20 03HE technical specifications

4
Installation
The SATK series H U is designed for installation in a sheltered
domestic environment (or similar), therefore cannot be installed or
used outdoors, i.e. in areas directly exposed to atmospheric
agents. Outdoor installation may cause malfunctioning and
hazards.
f the device is enclosed inside or between cabinets, sufficient
space must be provided for routine maintenance procedures. t is
advisable to avoid positioning electrical devices under the H U to
avoid the risk of damage in the event of leaks from hydraulic
fittings. f this advice is not heeded, the manufacturer cannot be
held responsible for any resulting damage.
n the event of a malfunction, fault or incorrect operation, the device
should be deactivated; contact a qualified technician for
assistance.
Preparation
After having established the point where the device has to be
installed, perform the following operations:
· Mark the holes required for securing the H U to the wall
· Mark the position of the hydraulic connections
Check the measurements again and begin laying the following
lines:
Hydraulic (see page 5):
1. connection to the central system line
2. heating circuit connection
3. domestic water circuit connection
Electric (see page 13):
1. 230 V (ac) – 50 Hz electric supply line
2. chrono-thermostat/thermostat line (potential-free)
3. centralised bus line for heat meter data transmission (if required)
4. centralised electric supply line for heat meter (if required)
Before installation, it is recommended to carry out accurate flushing
of all the pipes of the system in order to remove any residue or
impurities that could endanger correct operation of the H U.
Fix the H U to the wall.
N.B.: the wall anchors (not supplied) can only guarantee effective
support if inserted correctly (in accordance with good technical
practice) into walls built using solid or semi-solid bricks. If working
with walls built using perforated bricks or blocks, mobile dividing
panels or any masonry walls other than those indicated, a
preliminary static test must be carried out on the support system.
Electric connections
Make sure that the electrical system can withstand the maximum
power consumption of the appliance, with particular emphasis on
the cross-section of the cables.
f you have any doubts, contact a qualified technician to request a
thorough check of the electrical system.
Electrical safety of the appliance is only achieved when it is
correctly connected to an effective earthing system, made as
specified in current safety regulations. This is a compulsory safety
requirement.
Connection to the main supply
The device is supplied with an electric supply cable which is not
fitted with a plug.
The device should be electrically connected to a 230 V (ac) single-
phase + earth mains supply using the three-wire cable marked with
the label shown alongside, observing the L VE (L) - NEUTRAL (N)
polarities and the earth connection. This line must be connected to
a circuit breaker device.
Connection to the chrono-thermostat
The SATK series H U is fitted for connection to a thermostat or
chrono-thermostat, both standard and OpenTherm, for ambient
temperature adjustment.
The connection to this device (potential-free contact) must be
made with the two-wire cable marked with the label shown below.
Should it be necessary to extend this cable, use one with the same
cross-section (max 1 mm2) and maximum length 30 m.
Raumthermostat
(Potenzialfreier Kontakt)
Sonde d’ambiance
(Contact sec)
Termostato de ambiente
(Contacto sin potencial)
Ruimtesensor
(Schoon contact)
WARNING!
DO NOT CONNECT EXTERNAL
VOLTAGE SUPPLY TO THESE
TERMINALS
ATTENZIONE !
NON ALIMENTARE IN TENSIONE
Termostato ambiente
(Contatto pulito)
Room thermostat
(Volt free connection)
Fitting the cover
Place the casing over the frame, inserting the upper tabs (1) into
the corresponding slots (2).
Place the lower part of the casing over the frame.
Tighten the screws (3).
3
2
1
Commissioning
Filling the central heating system
Open the shut-off valves on the connections to the centralised line
and, in the central heating system, proceed with charging the
system to the design pressure.
Once these procedures are complete, vent the system and check
its pressure again (repeat the filling process if necessary)
System start-up
Before starting the H U, visually check the hydraulic connection
water-tightness and the electric wiring. After finishing the check,
activate the electric supply to the H U and check for the presence
of any error signals.
f there are any, eliminate the fault indicated and proceed as
described below, setting the set point of the domestic water and
heating cycles, programming the thermostat/chrono-thermostat
according to the desired temperatures and times, and checking the
operating cycles.

5
Heat meter installation
The H U is designed to fit a compact heat meter (with incorporated
return probe) with 1” threaded connections and 130 mm gauge.
Before carrying out any maintenance, repair or part replacement
work, proceed as follows:
- cut off the electric supply
- remove the cover
- close the shut-off valves
- empty the H U using the drain cocks provided
Proceed as described below to install the heat meter:
- remove the template (A)
- remove the cap (B)
- install the flow meter on the return pipe
- install the flow probe in the M10 pocket (B)
Please refer to the heat meter technical data sheets for further
information.
A
B
Hydraulic connections
Hydraulic connections to the centralised line must be implemented
using the manual shut-off valves supplied with the H U, which allow
any necessary maintenance work to take place without having to
empty the centralised system.
t is advisable to install manual shut-off valves (not supplied) also
on the bottom connections to the apartment circuits.
Before installation, it is recommended to carry out accurate flushing
of all the pipes of the system in order to remove any residue or
impurities that could endanger correct operation of the H U.
n order to facilitate these operations a manual bypass flushing
valve is available (code 789100).
N.B. Install the valves as shown in the figure
N.B.:
1 Install water hammer arresters to compensate for any overpressure in the domestic water circuit;
2 In the presence of hot water recirculation or if a non-return valve is fitted into the domestic cold water inlet, provision must be made to accomodate the expansion
of the water contained within the system and the heat interface unit;
3 All hydraulic connections must be checked before pressurising the system. Vibration during transport may cause the connections to become loose. DO NOT APPLY
EXCE IVE TIGHTENING TORQUE otherwise the components may be damaged.

6
• LCD display
Allows viewing of heating and domestic hot water set point
temperatures and the error codes.
Stand-by:
The following alternate every 5 seconds on the display:
The set point temperature is shown while the
symbol flashes:
(the return temperature is displayed if
temperature regulation with compensated set
point regulation is active, see page 9)
The set point temperature is shown while the
symbol flashes:
Domestic cycle ON:
Heating temperature set point
(the return temperature is displayed if
temperature regulation with compensated set
point regulation is active, see page 9)
60
60
48
Domestic hot water temperature set point
48
• Trimmers for set point settings
These allow setting of the temperature set point for the heating and
domestic water cycle (on low and medium temperature models)
and view the associated set value on the display.
• RESET key
User interface
The user interface, built into the PCB, consists of the following
devices:
• LED indicator
The various functions and faults are signalled by either flashing or
steady illumination of the LEDs.
ON - Electric supply 230 V (ac)
DHW - Domestic cycle
CH - Heating cycle
FAULT - Fault detected
Domestic cycle
Heating cycle
Operating principle
All heating and domestic hot water functions offered by
SATK20 series H Us are controlled by a digital controller.
The controller is factory set with different parameters and settings
depending on the model (Table 1).
There are a number of specific D P SW TCHES on the controller
circuit board; the way these are configured will determine the
settings of the various models and the optional functions enabled.
Electronic regulator
123456
This allows restoration of normal function after the
safety thermostat has been triggered and
activation/deactivation of the floor slab heating
function.
CODE SWITCH SETTING SET POINT
654321HEATING DHW
SATK20103HE
LOW temperature 25 – 45°C 42 – 60°C
SATK20203HE
MEDIUM temperature 45 – 75°C 42 – 60°C
SATK20303 / 20403HE / 20305
HIGH temperature - 42 – 60°C
Table 1 – factory default settings
Factory set (do not change)
May be changed to activate optional functions
Switch 1: modulating temperature regulation with compensated set point
Switch 5: domestic hot water pre-heating function
OFF
ON
OFF
ON
see page
13
Heating cycle ON:

7
Safety thermostat cut-out
SATK20103HE - LOW temperature
Error code 69
The H Us configured to support low temperature heating
continuously monitor the safety thermostat controlling the flow
temperature.
f the safety thermostat is activated during a general cycle, the
heating circulation pump immediately comes to a stop and the
modulating/mixing valve is completely closed. The thermal safety
lock valve (SATK20103HE) is closed.
n the event of a power failure, the thermal safety valve prevents hot
water from entering the heating system.
After the user has reset the block imposed by the safety thermostat,
the shut-off valve can only be re-enabled when the
mixing/modulating valves are completely closed again.
This means that if a domestic water cycle is in progress, the
activation of the shut-off valve will be postponed until the end of that
domestic water cycle.
Removing a fault
To restore the operating mode press the manual
RESET button.
Safety and alarms
Error codes associated with faults signalled by illumination of the
FAULT LED are also shown on the display.
69
Removing a fault
Normal operating conditions are restored automatically once the
faulty safety valve is working properly again.
Thermal safety valve fault
SATK20103HE - LOW temperature
Error code 76
76
Removing a fault
Normal operating conditions are restored automatically once the
faulty probe is working properly again (see page 12).
Probe fault
f a temperature probe fails, the associated cycle will be stopped
immediately and disabled.
Any requests to run cycles not associated to the previous one will
continue to run normally.
Heating probe fault
Error code: 5
5
Domestic hot water probe fault
Error code: 6
6
Compensation probe fault
SATK20103HE - SATK20203HE
Error code: 15
Automatic controller functions
Reset mixing/modulating valve to zero
mmediately after the power supply has been switched on, the
position of the installed mixing/modulating valves is reset to zero.
Pump anti-clog
When the pump is not in use, it is powered on for a period of
5 seconds every 24 hours.
Mixing valve/modulating valve anti-clog
The anti-clogging cycle for the mixing/modulating valve is run every
24 hours.
Removing a fault
Restore correct switch setting according to table 1
(page 6).
Incorrect switch setting
Error code 79
79
Removing a fault
The heat interface unit is disabled due to incorrect setting of the
dip-switches. Restore correct setting according to table 1
(page 6).
Incorrect dip-switch configuration (heat interface unit disabled)
Error code 80
80

8
Functional characteristics
Heating range 25 45°C
Set point regulation
DHW production range 42 60°C
Optional functions
Domestic cycle: - DHW pre-heating function
Heating cycle: - modulating temperature regulation
with compensated set point
- floor slab heating function
Factory settings
Characteristic components
2
1
3
4
7
5
6
9
14
10
12
11
13
15
17
8
10
16
18
1 23 45 6 4
ON
1. Frame
2. Electronic regulator
3. Thermal safety relief valve
4. Heating mixing valve
5. DHW production modulating valve
6. Heating flow temperature probe
7. Thermal safety thermostat
8. DHW temperature probe
9. DHW heat exchanger
10. Drain cock
11. Flow temp. compensation return probe
12. Pump UPM3 15-70
13. DHW priority flow meter
14. Protective pump by-pass
15. Heat meter spacer template
16. Air vent cock
17. System strainer/heat meter flow probe pocket
18. Primary circuit shut-off valves
SATK20103HE LOW temperature heat interface unit ith high efficiency pump
Functional characteristics
Heating range 45 75°C
Set point regulation
DHW production range 42 60°C
Optional functions
Domestic cycle: - DHW pre-heating function
Heating cycle: - modulating temperature regulation
with compensated set point
2
1
3
4
5
7
12
8
9
11
13
15
6
14
16
10
1. Frame
2. Electronic regulator
3. Heating mixing valve
4. DHW production modulating valve
5. Heating flow temperature probe
6. DHW temperature probe
7. DHW heat exchanger
8. Drain cock
9. Flow temp. compensation return probe
10. Pump UPM3 15-70
11. Protective pump by-pass
12. DHW priority flow meter
13. Heat meter spacer template
14. Air vent cock
15. System strainer/heat meter flow probe pocket
16. Primary circuit shut-off valves
SATK20203HE MEDIUM temperature heat interface unit ith high efficiency pump
Characteristic components
Factory settings
1 23 45 6 4
ON
** see page 13

9
5
ON
1
OFF
Operating cycles
Domestic water cycle
This cycle always takes priority over the heating cycle
When DHW cycle activation is requested due to DHW tapping by
the user detected by the domestic water flow meter, the regulator
controls the opening of the modulating valve in order to adjust the
temperature detected by the domestic water probe to the selected
set point value.
When tapping ends, the modulating valve is fully closed.
The active domestic hot water cycle is signalled by yellow DHW
LED steady on.
The domestic hot water cycle temperature set point can be set
using trimmer P1 and shown on the display.
Heating cycle
Set point regulation
When heating cycle activation is requested by the room thermostat,
the circulation pump is powered while the mixing valve is activated
gradually until the set point temperature is reached.
At the end of the heating cycle, the circulation pump comes to a
stop and the valve is closed.
The active heating cycle is signalled by yellow CH LED steady on.
The heating cycle temperature set point can be set using trimmer P2
and shown on the display.
Floor slab heating function - SATK20103HE
Facilitates the installation of underfloor heating systems at low
temperatures. This function can only be activated and executed if
there are no faults.
t can be activated by pressing and holding the RESET button for 8
seconds.
The yellow CH LED blinks while the floor slab heating function is in
operation.
The function lasts 240 hours and is carried out by simulating a
request to run in heating mode starting from a set point of 25°C and
rising in regular intervals to a temperature of 45°C. Once the
maximum set point has been reached, the function is executed,
following the same procedures, in reverse (from the maximum set
point to the minimum set point).
This function has priority over heating and hot water cycles, and
can be suspended at any time by pressing and holding the RESET
button for 8 seconds.
Optional functions (to activate/deactivate the optional functions
the electric power supply must always be turned off!)
Domestic cycle
DHW pre-heating function
The function is enabled by setting dip switch 5 to the ON position.
During periods when the domestic water cycle is not used, if the
DHW probe detects a temperature 10°C below the SET value, the
controller partially opens the domestic hot water modulating valve for
the time required (max. 5 min.) to bring the exchanger to the
condition wherein it can assure rapid DHW production.
The domestic hot water pre-heating function is signalled by the
flashing yellow DHW LED.
This function is less of a priority than any domestic water or heating
cycles.
Heating cycle
Modulating temperature regulation with compensated set point
SATK20103HE - SATK20203HE
The function is enabled by setting dip switch 1 to the OFF position.
When the function is enabled, the flow temperature is modified
according to the temperature detected by the compensation probe
(located on the user return pipe). This allows constant monitoring of
the effective thermal output of the floor slab with the consequent
minimisation of system response times.
f the function is enabled the display shows the return temperature,
and the flow temperature is adjusted in accordance with the
following formula:
Flow temperature = Return temperature +
D T
n MEDIUM/HIGH temperature configuration: DT 8–22°C
n LOW temperature configuration: DT 2–8°C
48
60
25
48
60
8 seconds

10
Functional characteristics
Maximum heating temp. 85°C
ON/OFF regulation
DHW production range 42 60°C
Optional functions
Domestic cycle: - DHW pre-heating function
1
2
3
4
5
13
12
11
10
9
7
6
8
1. Frame
2. Electronic regulator
3. Heating ON/OFF valve
4. DHW production modulating valve
5. Drain cock
6. DHW temperature probe
7. DHW heat exchanger
8. DHW priority flow meter
9. Pump (SATK20403HE only) UPM3 15-70 with protective
by-pass
10. Heat meter spacer template
11. System strainer/heat meter flow probe pocket
12. Air vent cock
13. Primary circuit shut-off valves
Characteristic components
Factory settings
1 23 45 6 4
ON
Functional characteristics
Maximum heating temp. 85°C
ON/OFF regulation
DHW production range 42 60°C
Optional functions
Domestic cycle: - DHW pre-heating function
1
2
3
4
5
12
11
10
9
8
7
6
1. Frame
2. Electronic regulator
3. Heating ON/OFF valve
4. DHW production modulating valve
5. Drain cock
6. DHW temperature probe
7. DHW heat exchanger
8. DHW priority flow meter
9. Heat meter spacer template
10. Air vent cock
11. System strainer/heat meter flow probe pocket
12. Primary circuit shut-off valves
SATK20305 High capacity HIGH temperature heat interface unit
Characteristic components
Factory settings
1 23 45 6 4
ON
SATK20303 HIGH temperature heat interface unit
SATK20403HE HIGH temperature heat interface unit ith high efficiency pump on the primary side

11
Operating cycles
Domestic water cycle
This cycle always takes priority over the heating cycle.
When DHW cycle activation is requested due to DHW tapping by
the user detected by the domestic water flow meter, the regulator
controls the opening of the modulating valve in order to adjust the
temperature detected by the domestic water probe to the selected
set point value.
When tapping ends, the modulating valve is fully closed.
The active domestic hot water cycle is signalled by yellow DHW
LED steady on.
The general domestic water cycle temperature set point can be set
using trimmer P1 and shown on the display.
Heating cycle
ON-OFF regulation
When the room thermostat requests the start of a heating cycle, the
valve is opened completely, allowing water to circulate at the
temperature supplied by the central heating system (ON/OFF
regulation).
The valve is closed on completion of the heating cycle.
The active heating cycle is signalled by lighting of the yellow CH LED.
No value is shown on the display.
Optional functions (to activate/deactivate the optional functions
the electric power supply must always be turned off!)
Domestic cycle
DHW pre-heating function
The function is enabled by setting dip switch 5 to the ON position.
During periods when the domestic water cycle is not used, if the
DHW probe detects a temperature 10°C below the SET value, the
controller partially opens the domestic hot water modulating valve for
the time required (max. 5 minutes) to bring the exchanger to the
condition wherein it can assure rapid DHW production.
The domestic hot water pre-heating function is signalled by the
flashing yellow DHW LED.
This function is less of a priority than any domestic water or heating
cycles.
48
––
48
5
ON

12
Maintenance
All maintenance procedures should be carried out by an authorised
technician.
Regular maintenance guarantees better efficiency and helps to
save energy.
Before carrying out any maintenance, repair or part replacement
work, proceed as follows:
- Cut off the electric supply
- Remove the cover
- Close the shut-off valves
- Empty the heat interface unit using the drain cocks provided.
Heat exchanger replacement
- Remove the heat exchanger, loosening the 2 hex socket head
screws fixing it in place (A)
- Replace the heat exchanger and the O-Rings.
- Tighten the two fixing screws (A).
N.B. The pins fixing the heat exchanger are positioned in such a way
as to allow it to be placed only in the correct direction.
Strainer cleaning
All heat interface units have a strainer on the inlet for water from the
centralised system.
To clean these strainers, carry out the following maintenance
procedure:
- Unscrew the cap (B)
- Remove the strainer mesh and discard any impurities
- Put the strainer mesh back in
- Screw the cap back on.
Temperature probe replacement
- Disconnect the probe cable, lightly folding the tab (C) and
extracting the connector (see page 13, ref. 1-3-7)
- Unscrew the probe
- Fit the new probe
- Reconnect the connector respecting the only possible way it can
be inserted.
Replacing the valve actuator
- Disconnect the actuator cable, lightly pressing the tab on the
connector and extracting it (see page 13, ref. 4-8)
- Extract the fixing clip (D) and then the actuator
- Position the new actuator (E)
- nsert the fixing clip, respecting the correct direction
- Reconnect the connector.
Replacing the valve obturator
- Disconnect the valve actuator (see previous paragraph)
- Extract the obturator, unscrewing the locking nut (F)
- Replace the obturator, screw on the locking nut (F) and then
insert the actuator
- nsert the fixing clip, respecting the correct direction
- Reconnect the connector.
Replacing the DHW priority flow meter
- Disconnect the flow meter cable acting on the connector (see
page 13, ref. 2)
- Extract the flow sensor (G)
- Position the new sensor
- Reconnect the connector respecting the only possible way it can
be inserted.
Replacing or cleaning the priority flow meter turbine and strainer
- Extract the flow sensor (G)
- Unscrew and remove the cartridge (H)
- Eliminate any impurities on the strainer mesh and, if necessary,
change the cartridge
- Screw the cartridge back into place
- Refit the flow sensor.
When carrying out maintenance on the electrical part, for the
connections follow the diagram on page 13.
After concluding maintenance, proceed with the filling and
checking operations described in the chapter “Commissioning”
and fit the cover. f you require any information regarding spare
parts, please contact Caleffi spa.
A
A
C
B
D
E
F
G
H

13
Electric connections
FUSE 5x20
12 3 46
5
9
10
13
11
12
6 35 4 21
14
s5SARESOLOPERCOLLEGAMENTOACODs5SETHISWIREFORCONNECTIONTOCODEONLYs°NgUTILISERQUEPOURLALIAISONAVECCODEs6ERWENDEN3IEDIESES'ERËTNURZUM!NSCHLUSSANDIE!RT.Rs'EBRUIKDEZEENKELVOORAANSLUITINGOPCODEs5TILICESOLAMENTEPARALACONEXIØNCONCØDs5SARESOLOPERCOLLEGAMENTOACODs5SETHISWIREFORCONNECTIONTOCODEONLYs°NgUTILISERQUEPOURLALIAISONAVECCODEs6ERWENDEN3IEDIESES'ERËTNURZUM!NSCHLUSSANDIE!RT.Rs'EBRUIKDEZEENKELVOORAANSLUITINGOPCODEs5TILICESOLAMENTEPARALACONEXIØNCONCØD
78
Raumthermostat
(Potenzialfreier Kontakt)
Sonde d’ambiance
(Contact sec)
Termostato de ambiente
(Contacto sin potencial)
Ruimtesensor
(Schoon contact)
Termostato ambiente
(Contatto pulito)
Room thermostat
(Volt free connection)
* This connection may not be available
** To be wired during installation
(Room thermostat not supplied)
(potential-free
line)
MAX 30 m
6
ON
Dip-switch 6 configuration
f the regulator is equipped with the “H U enabling” cable
(refer to line 14 in the above table), dip-switch 6 must be
set to OFF
Vice versa, if this connection is absent, the dip-switch
must be set to ON.
6
ON
SATK20103HE
SATK20203HE
SATK20303 SATK20305
SATK20403HE
1DHW temperature probe xxxx
2 DHW priority flow meter xxxx
3Flow temp. compensation return probe xx
4 DHW production valve actuator xxxx
5 Thermal safety thermostat x
6 Thermal safety valve x
7 Heating flow temperature probe xx
8 Heating valve actuator xxxx
9 Earth xxxx
10 Pump xx x
11 Electric supply 230V (ac)** xxxx
12 Room thermostat** xxxx
13 Fuse xxxx
14 H U enabling *xxx
N.B.:
The pump cable connector is polarised. nsert the connector correctly and
do not attempt to force it in the wrong position.

14
FAULT DESCRIPTION INDICATIONS POSSIBLE CAUSE OF FAULT OPERATIONS TO BE PERFORMED
Water is not
heated
DHW LED on
primary circuit shut-off valves closed open the valves
modulating valve actuator connector disconnected reconnect actuator connector
modulating valve actuator disconnected from valve body reconnect actuator
modulating valve actuator faulty call qualified personnel to have it
replaced
DHW temperature probe cable inverted with heating
probe restore correct connection
presence of air in the system vent the system
electronic controller not working call qualified personnel to have it
replaced
valve obturator blocked in closed position call qualified personnel to have it
replaced
centralised system not working/cold contact person in charge of system
FAULT LED on + error
code 6 active
DHW temperature probe disconnected reconnect probe
DHW temperature probe faulty call qualified personnel to have it
replaced
FAULT LED on + error
code 79 active
incorrect switch setting restore correct switch setting
F AULT LED on + error
code 80 active
incorrect switch setting restore correct switch setting
DHW led off
DHW priority flow meter disconnected reconnect flow meter
DHW priority flow meter faulty call qualified personnel to have it
replaced
all LEDs are off
No electric power supply restore H U electric supply
protection fuse burnt out call qualified personnel to have it
replaced
The water is hot
but does not
reach the
desired
temperature
DHW LED on
domestic water cycle temperature set point too low increase set point
Primary circuit strainer of the H U clogged call qualified personnel to have it
serviced
heat exchanger partly clogged call qualified personnel to have it
serviced
modulating valve actuator faulty call qualified personnel to have it
replaced
valve obturator blocked in intermediate position call qualified personnel to have it
replaced
DHW temperature probe cable inverted with heating
probe restore correct connection
excessive demand for DHW decrease demand
electronic controller not working call qualified personnel to have it
replaced
centralised system temperature insufficient contact person in charge of system
primary circuit flow rate insufficient contact person in charge of system
Hot water
temperature is
too high
DHW LED on
domestic water cycle temperature set point too high decrease set point
DHW temperature probe cable inverted with heating
probe restore correct connection
modulating valve actuator faulty call qualified personnel to have it
replaced
valve obturator blocked in intermediate or open position call qualified personnel to have it
replaced
electronic controller not working call qualified personnel to have it
replaced
primary circuit excessive pressure contact person in charge of system
Hot water flow
rate is
insufficient
DHW LED on
flow meter strainer clogged call qualified personnel to have it
serviced
possible domestic water system shut-off valves
partially closed open the valves
centralised domestic circuit cold water flow rate
insufficient
call qualified personnel to have it
serviced
Hot water flow
rate is zero DHW LED off
possible domestic water system shut-off valves closed open the valves
no cold water in centralised domestic circuit call qualified personnel to have it
serviced
flow meter strainer completely clogged call qualified personnel to have it
serviced
heat exchanger completely blocked call qualified personnel to have it
serviced
Troubleshooting

15
FAULT DESCRIPTION INDICATIONS POSSIBLE CAUSE OF FAULT OPERATIONS TO BE PERFORMED
The room
is not reaching
the desired
temperature
CH LED on
heating cycle temperature set point too low increase set point
chrono-thermostat temperature setting incorrect check programming of chrono-
thermostat
H U strainer clogged call qualified personnel to have it
serviced
heating valve actuator faulty call qualified personnel to have it
replaced
heating valve obturator blocked call qualified personnel to have it
replaced
modulating valve actuator connector disconnected reconnect actuator connector
DHW temperature probe cable inverted with heating
probe restore correct connection
presence of air in the system vent the system
pump (if present) not working call qualified personnel to have it
replaced
pump cable (if present) not connected restore connection
possible system shut-off valves/terminals closed open the valves
centralised system temperature insufficient contact person in charge of system
electronic controller not working call qualified personnel to have it
replaced
primary circuit flow rate insufficient contact person in charge of system
centralised system not working contact person in charge of system
CH LED off chrono-thermostat time setting incorrect check programming of chrono-
thermostat
chrono-thermostat not working check chrono-thermostat
all LEDs are off
Electric supply cut off restore H U electric supply
Protection fuse burnt out call qualified personnel to have it
replaced
FAULT LED on + error
code 5 active
heating temperature probe faulty call qualified personnel to have it
replaced
FAULT LED on + error
code 15 active
compensation temperature probe faulty call qualified personnel to have it
replaced
FAULT LED on + error
code 69 active
safety thermostat cut-out call qualified personnel to have it
serviced
FAULT LED on + error
code 76 active
safety relief valve faulty call qualified personnel to have it
serviced
FAULT LED on + error
code 79 active
incorrect switch setting restore correct switch setting
F AULT LED on +
error code 80 active
incorrect switch setting restore correct switch setting
Start-up of the
heat interface
unit heating
function triggers
the safety circuit
breaker
All LEDs are off pump connector inserted the wrong way round check that the pump cable connector is
inserted the right way round

Commissioning checklist
Model Checks to be performed
1 all s the heat interface unit properly secured to the wall?
2 all Has the system flushing been carried out?
3 all Check strainers and clean them if necessary
4 all s the heat meter (if present) connected?
5 all s the heat meter (if present) connected to the building datalogger (if required)?
6 all s the DCW line fitted with a pressure reducing valve?
7 all s the system protected by water hammer arresters?
8 all Has the domestic exchanger pre-heating function (normally off) been activated (if
required)?
9SATK20103HE
SATK20203HE
Has the modulating temperature regulation with compensated set point (normally off)
been activated (if required)?
10 all s the heat interface unit connected to the 230 V (ac) electric supply?
11 all s the room thermostat (potential-free contact) connected?
12 all
Has the visual inspection of electrical connections inside the heat interface unit given
a positive result?
Are the connections compliant with specifications and made in accordance with best
practices?
13 all Are the shut-off valves open?
14 all Has the visual inspection of the hydraulic connections given a positive result?
15 all Has the system been filled and vented?
16 all s the heat interface unit powered (green “ON” LED lit)?
17 all No alarm code (“fault” LED lit) on heat interface unit regulator?
18 all Has the DHW temperature been set to the required value?
(42–50°C recommended)
19 SATK20103HE
SATK20203HE Has the heating flow temperature been set to a correct value?
20 all s the primary circuit at working temperature?
21 all Check that “CH” LED lights approx. 10 seconds after the thermostat trips
22
SATK20103HE
SATK20203HE
SATK20403HE
Check that the pump operates correctly on tripping of the thermostat
(check that secondary flow pipes start to heat up)
23 all Simulate minimal DHW tapping (approx 3 l/min) and check that “DHW” LED lights
and that water is supplied at the required temperature
24 all Simulate abundant DHW tapping and check, by means of the installed heat meter,
that the primary circuit flow rate is sufficiently high