Thermocold MEX VS 15 RH User manual

CONTROLLER MANUAL FOR CHILLERS AND
INVERTER AIR/WATER HEAT PUMPS WITH
AXIAL FANS
MANUALE DEL CONTROLLO
MEX VS 15 RH / MEX VS 16 RH
MEX VS 18 RH /
MEX VS 19 RH
MEX VS 112 RH
/MEX VS 112T RH
MEX VS 115 RH
/ MEX VS 115T RH
Cod.
MCO14124H7800-02
CONTROLLER MANUAL
MEX VS 15 RH / MEX VS 16 RH
MEX VS 18 RH / MEX VS 19 RH
MEX VS 112 RH /MEX VS 112T RH
MEX VS 115 RH / MEX VS 115T RH
Cod. MCO14124H7820-02
Questo manuale è stato creato per scopo informativo. La ditta declina ogni responsabilità per i risultati di una progettazione o di una installazione basata sulle spiegazioni e le specifiche
tecniche riportate in questo manuale. E’ inoltre vietata la riproduzione anche parziale sotto qualsiasi forma dei testi e delle figure contenute in questo manuale.
Manuale in lingua originale

Controller for MEX VS Chillers and inverter air / water heat pumps with axial fans
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INDEX
1CONSERVATION OF THE MANUAL.......................................................................................................................................... 3
1.1 GRAPHIC SYMBOLS................................................................................................................................................................. 3
2PERMITTED USES ................................................................................................................................................................... 3
3GENERAL SAFETY RULES......................................................................................................................................................... 3
3.1 PERSONAL SAFETY EQUIPMENTS ........................................................................................................................................... 3
3.2 WORKERS’ HEALTH AND SAFETY ............................................................................................................................................ 3
4PURPOSES AND CONTENTS OF THE MANUAL......................................................................................................................... 5
5USER’S INTERFACE - CONTROLER ........................................................................................................................................... 5
5.1 MENU STRUCTURE DIAGRAM ................................................................................................................................................ 5
5.2 ANALOG INPUT MENU............................................................................................................................................................ 6
5.3 PARAMETERS CATEGORIES .................................................................................................................................................... 6
5.4 SETPOINT ADJUSTABLE BY THE USER...................................................................................................................................... 6
5.5 DISPLAY .................................................................................................................................................................................. 7
5.6 LED ......................................................................................................................................................................................... 7
5.7 INPUT/OUTPUT (I/O) PORTS................................................................................................................................................... 7
6DYNAMIC SET-POINT ADJUSTMENT ....................................................................................................................................... 8
7SET-POINT ADJUSTMENT FROM 0-10V INPUT ........................................................................................................................ 8
8CIRCULATOR .......................................................................................................................................................................... 9
8.1 OPERATION BY MEAN OF THERMOREGULATOR (DEFAULT) ..................................................................................................... 9
8.2 OPERATION BY THERMOREGULATOR WITH PERIODIC ACTIVATION .................................................................................... 10
8.3 OPERATION WITH ACTIVE ELECTRIC HEATER ....................................................................................................................... 10
8.4 CONTINUOUS OPERATION ................................................................................................................................................... 10
8.5 PROPORTIONAL ADJUSTMENT OF THE PUMP ...................................................................................................................... 10
8.6 PURGING THE SYSTEM.......................................................................................................................................................... 11
9HEAT DISSIPATION FAN MOTOR CONTROL .......................................................................................................................... 11
9.1 FAN SPEED CONTROL IN COOLING MODE ............................................................................................................................ 11
9.2 FAN SPEED CONTROL IN HEATING MODE............................................................................................................................. 12
10 CONTROL FUNCTIONS ...................................................................................................................................................... 12
10.1 ALARM WARNING ................................................................................................................................................................ 12
10.2 ANTIFREEZE PROTECTION ELECTRIC HEATERS (WHEN THE KA ACCESSORY IS PRESENT)...................................................... 12
10.3 ACTIVATION OF SANITARY (DOMESTIC) HOT WATER PRODUCTION .................................................................................... 12
10.3.1 SENSOR MEMORIZATION IN HEATING MODE .............................................................................................................. 13
10.4 HEATING MODE ON SANITARY ACCUMULATION ................................................................................................................. 14
10.5 REMOTE FUNCTIONS............................................................................................................................................................ 15
10.5.1 ON/OFF......................................................................................................................................................................... 15
10.5.2 SUMMER/WINTER MODE COMMUTATION ................................................................................................................. 15
10.5.3 SANITARY MODE CALL FROM DIGITAL INPUT .............................................................................................................. 15
10.6 REMOTE SENSOR FOR THE WATER TEMPERATURE OF THE PLANT CIRCUIT......................................................................... 16
10.7 AUXILIARY ELECTRIC HEATER................................................................................................................................................ 16
10.7.1 PLANT CIRCUIT ELECTRIC HEATER ................................................................................................................................ 16
10.7.2 AUXILIARY ELECTRIC HEATER OF THE PLANT IN DEFROST CYCLE ................................................................................. 16
10.7.3 ELECTRIC HEATER OF SANITARY WATER PRODUCTION ............................................................................................... 17
10.7.4 A UNIQUE AUXILIARY ELECTRIC HEATER FOR BOTH PLANT SYSTEM/DHW PRODUCTION........................................... 17
10.8 SELECTION MODE OF AUXILIRY ELECTRIC HEATERS ............................................................................................................. 17
10.9 MANAGEMENT OF THE CIRCULATOR WITH ACTIVE ELECTRIC HEATER ................................................................................ 17
10.10 BOILER ENABLEMENT........................................................................................................................................................... 17
10.11 ACTIVATION OF AUXILIARY ELECTRIC HEATERS AND BOILER DURING THE JOINT AND IN SUBSTITUTION OPERATION TO THE
COMPRESSOR OF THE HEAT PUMP .................................................................................................................................................. 18
10.11.1 OPERATION IN HEAT PUMP MODE .......................................................................................................................... 18
10.11.2 IN JOINT OPERATION (AREA I) .................................................................................................................................. 18
10.11.3 IN JOINT OPERATION (AREA II) ................................................................................................................................. 18
10.11.4 IN SUBSTITUTION OPERATION ................................................................................................................................. 19

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10.12 OPERATION AREA -ACTIVATION OF THE AUXILIARY ELECTRIC HEATER AND BOILER (PLANT CIRCUIT WATER TEMPERATURE SENSOR
IS NOT ENABLED)................................................................................................................................................................................... 19
10.12.1 AUXILIARY SYSTEMS OFFSET MANAGEMENT........................................................................................................... 22
10.13 SUMMER/WINTER OPERATION INDICATION ....................................................................................................................... 23
10.14 DEFROSTING CYCLE .............................................................................................................................................................. 23
10.15 COMPRESSOR CRANCKASE HEATER ..................................................................................................................................... 23
10.16 MANAGEMENT OF THE SECONDARY CIRCULATOR/RELAUNCHING PUMP (WITH ROOM THERMOSTAT) .................................... 23
10.17 MAXIMUM HZ.......................................................................................................................................................................... 24
10.18 DOUBLE SET-POINT (WITHOUT REMOTE CONTROL HI-T) .............................................................................................................. 24
10.18.1 CONTROL SETTINGS.................................................................................................................................................. 24
10.18.2 NOTES FOR INSTALLATION ....................................................................................................................................... 24
10.18.3 HUMIDISTAT OPERATION ......................................................................................................................................... 25
10.18.4 ADJUASTABLE SET-POINT ......................................................................................................................................... 25
10.18.5 COMMUTATION ....................................................................................................................................................... 25
10.18.6 HUMIDISTAT WIRING ............................................................................................................................................... 26
11 AVAILABLE FUNCTIONS WITH HI-T ACCESSORY ................................................................................................................ 26
12 AVAILABLE FUNCTIONS WITH KIE MODULE (OPTIONAL) .................................................................................................. 26
13 HANDBOOK FOR CONFIGURATIONS OF INSTALLATION.................................................................................................... 26
14 TABLES OF CONFIGURATIONS ALLOWED TO USER AND INSTALLER.................................................................................. 26
15 ALARMS ........................................................................................................................................................................... 32
15.1 WATER FLOW SWITCH ALARM E06....................................................................................................................................... 32
15.2 HIGH TEMPERATURE E18 ..................................................................................................................................................... 32
15.3 ANTI-FREEZING E05 .............................................................................................................................................................. 32
15.4 SENSORS ALARM E611÷E691................................................................................................................................................ 32
15.5 TIMEOUT INVERTER E801..................................................................................................................................................... 32
15.6 INVERTER [E851÷E971]......................................................................................................................................................... 32
15.7 REMOTE ON/OFF E00 ........................................................................................................................................................... 32
15.8 HIGH PRESSURE E01 ............................................................................................................................................................. 32
15.9 HIGH PRESSURE FLOW SWITCH (IN SERIES WITH THE COMPRESSOR OUTLET PROBE) E641 ................................................ 32
15.10 LOW PRESSURE E02.............................................................................................................................................................. 32
15.11 [E08] DRIVER LIMITATION .................................................................................................................................................... 32
15.12 [E41] 4-WAY VALVE .............................................................................................................................................................. 33
15.13 [E42] DOMESTIC HOT WATER PROTECTION ......................................................................................................................... 33
15.14 POWER FAILURE ................................................................................................................................................................... 33
15.15 USER BLOCK ALARM LIST ...................................................................................................................................................... 33

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1CONSERVATION OF THE MANUAL
The manual has to be always kept for future reference. It has to be stored in a safe place, away from dusts and moisture. It has to
be also available and accessible to all users who shall consult it any time they are in doubt on how to operate the equipment.
The company reserves the right to modify its products and related manuals without necessarily updating previous versions of the
reference material. It declines also any responsibility for possible inaccuracies in the manual if due to printing or transcription
errors.
The customer shall store any updated copy of the manual or parts of it delivered by the manufacturer as an attachment to this
manual.
The company is available to give any detailed information about this manual and to give information regarding the use and the
maintenance of its own units.
1.1 GRAPHIC SYMBOLS
Indicates prohibited operations.
Indicates operations that can be dangerous for people and/or disrupts the correct operation of the equipment.
Electric shock hazard - risk of electric shock.
Indicates important information that the operator has to follow in order to guarantee the correct operation of the
equipment in complete safety. It indicates also general notes.
2PERMITTED USES
The company excludes any contractual and extra contractual liabilities for damages caused to persons, animals or objects, by
incorrect installation, setting and maintenance, improper use of the equipment, and the partial or superficial reading of the
information contained in this manual.
These units have been designed only for heating and/or cooling water. Any other use not expressly authorized by the
manufacturer is considered improper and therefore not allowed.
The location of the plant, the hydraulic and electrical circuits must be established by the planting designer and must take into
account both technical requirements as well as any applicable local laws and authorized specifications.
The execution of all works must be performed by skilled and qualified personnel, competent in the existing rules in different
countries.
3GENERAL SAFETY RULES
Before beginning to operate on the units every user has to be perfectly knowledgeable about the functions of the equipment and
its controls and has to have read and understood the information listed in the user’s-installer’s manual.
3.1 PERSONAL SAFETY EQUIPMENTS
During the operating and maintaining works, use the following personal protective equipment.
Protective clothing: Maintenance men and operators have to wear protective clothing that complies with the basic
safety requirements currently in force. In case of slippery floors, users have to wear safety shoes with non-slip soles.
Gloves: During maintenance or cleaning operation protection gloves have to be used
Mask and goggles: Respiratory protection (mask) and eye protection (goggles) should be used during
cleaning and maintenance operations.
3.2 WORKERS’ HEALTH AND SAFETY
The European Community has adopted a number of directives on workplace’s health and safety, which include 89/391/CEE,
89/686/CEE, 2009/104/CE, 86/188/CEE and 77/576/CEE directives. Every employer shall implement such provisions and ensure
that their workers to respect them.
It’s forbidden:
To remove and/or tamper with any safety device.
The access to the electrical board by unauthorized persons
To carry out any work on the equipment under voltage
To touch the equipment if you are not allowed.
The use of the appliance by children or unassisted disabled persons.
To touch the appliance when barefoot or parts of the body are wet or damp
To clean the unit when the power is ‘ON’.
To pull, remove or twist the electrical cables coming out from the unit.

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To step with your feet on the appliance, sit down and/or place any type of object.
To spray or pour water directly on the unit.
To dispose of, abandon or leave within reach of children packaging materials (cardboard, staples, plastic bags, etc.) as they
may represent an environmental and health hazards.
To tamper with or replace parts of the equipment without the specific consent of the manufacturer. The manufacturer shall
have no whatsoever civilian or penal responsibility in case of unauthorized operations.
WARNING:
Before proceeding, you should read the user’s-installer manual accompanying appliance.
All the operations described below must be carried out only by QUALIFIED PERSONNEL.
The wiring to the terminal block must be performed by qualified personnel.
Any routine and/or not-routine maintenance operation shall be carried out when the equipment has been shut down,
disconnected from electric power supply.
Do not put neither your hands nor insert screwdrivers, spanners or other tools into moving parts of the equipment
The equipment’s supervisor and the service man have to receive suitable training for performing their tasks in safety.
The access to the electric panel is limited to authorized personnel only.
Operators have to know how to use personal protective devices and have to know the accident-prevention guidelines
contained in national and international laws and norms.
The operator’s workplace has to be kept clean, tidy and free from objects that may prevent free movements. Appropriate
lighting of the work place shall be provided so as to allow the operator to carry out the required operations safely. Poor or too
strong lighting can cause risks.
Ensure that the work places are always adequately ventilated and that aspirators are working, in good condition and in
compliance with the requirements of the laws in force.
Not all the configurations can be simultaneously enabled and/or changed.
Other values different than those of default can ensure the proper operation of the unit, in case of doubt about the value to be
set contact please our office.
The company excludes any contractual and extra contractual liabilities for damages caused to persons, animals or objects, by
incorrect installation, setting and maintenance, improper use of the equipment, and the partial or superficial reading of the
information contained in this guide.
The supply voltage’s fluctuations cannot exceed ±10% of the nominal value. If this tolerance should not be respected, please
contact our technical department.
The power supply should respect the listed limits: failing this, warranty will not be valid immediately. Before any operation on
the unit, be sure that the power supply is disconnected.
Phase, neutral and ground connections should be respected.
The power supply cables must be sized correctly. We recommend a minimum cross section of 4mm2and a maximum length of
10m.
Install upstream of each unit an adequate protection and disconnection device of the electric power with delayed
characteristic curve, with at least 3 mm contact opening and with an adequate capacity of breaking and differential protection.
The capacity of the magneto-thermic circuit breaker must conform to the electric consumption of the unit; see TECHNICAL DATA
reported in the user’s-installer’s manual accompanying the unit. (Consideration should be taken of any eventual auxiliary
electric heater).
A good grounding is required; the manufacturer is not responsible for damage caused in case of lack of good grounding.
In case of maintenance, the unit must be disconnected from the power supply, the power cable plug must be easy for pulling it
out from the power socket by the operator for having possibility to check the unit from anywhere, the plug should remain
disconnected.
Use cables that meet the regulations in force in different countries.
Be sure, after about 10 minutes of operation the screws on the power supply terminal block that are well fixed.
Requirements before performing electrical work on the control panel:
Turn off the unit from the control panel ("OFF" displayed).
Put the switch “QF” general differential on OFF position
wait for 15 seconds before getting access to the electric board
Check the ground connection before beginning any operation.
Be sure that you are well insulated from the ground, with dry hands and feet, or by using insulating platforms and gloves.
Check that there is no foreign material near the system.

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4PURPOSES AND CONTENTS OF THE MANUAL
This manual provides basic information for the installation, operation and maintenance of MEX VS units.
It is addressed to machine operators and it enables them to use the equipment efficiently, even if they do not have any previous
specific knowledge of it.
Not all the described functions can be individually and/or simultaneously selected. Please contact the technical office for any
information.
The manual describes the characteristics of the equipment at the time in which it is being put on the market; therefore, it may not
include technological improvements introduced later by the company as part of its constant endeavour to enhance the
performance, ergonomics, safety and functionality of its products.
The company introduces also technological improvements and is not constrained to update the manuals for previous versions of
appliances that could not be compatible. So make sure to use manual supplied with the installed appliance.
It’s recommended that, the user must follow the instructions contained in this booklet, especially those concerning the safety and
routine maintenance.
5USER’S INTERFACE - CONTROLER
It is used to select the operating mode, and to reset the manual resetting alarms. The operating
mode changes as per the sequence below each time you press the Mode button:
off cool heat off
If the Domestic Hot Water (DHW) mode is enabled, the sequence is as follows:
off cool cool+sanheat heat+sanoff
During the parameters’ setting, this button can be used to revert BACK to the previous level.
It allows you to enter into the setting menu parameters and to select the cool/summer,
heat/winter and DHW set point value.
UP button: In the setting mode, this button allows you to move up to a higher menu or to increase
the value of a parameter when you are in the “edit” mode.
DOWN button: In the setting mode, this button allows you to shift to a lower menu or to decrease
the value of a parameter when you are in the “edit” mode.
5.1 MENU STRUCTURE DIAGRAM
Level 0 (U) = always appearing
Level 1 (M) = it appears if you enter the maintainer (H80) or manufacturer password.

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Level 2 (C) = it appears if you enter the manufacturer password.
Level 3 (A) = it appears only via Modbus.
5.2 ANALOG INPUT MENU
By entering the maintainer password in the menu of analog inputs "tP", at the level 1 of the menu structure diagram of the unit
control board, you can read the values of the current probes:
tp
DESCRIPTION
Measurement unit
t01
Inlet water temperature
(°C)
t02
Outlet water temperature
(°C)
t03
Compressor inlet temperature
(°C)
t04
Compressor outlet temperature
(°C)
t05
High pressure
(bar)
t06
Low pressure
(bar)
t07
Outdoor air temperature
(°C)
t08
Plant remote temperature senor (if enabled)
(°C)
t09
Domestic hot water temperature (if DHW is enabled)
(°C)
t10÷t27
Parameters presents if installed the optional KIE module
-
5.3 PARAMETERS CATEGORIES
The parameters are classified into groups, each group is identified by a 3-digit code, while the index of each parameter is preceded
by one letter.
DESCRIPTION
GROUP IDENTIFICATION CODE
PARAMETER INDEX
VISIBILITY
Configuration
CnF
H-
USER / INSTALLER
Compressor
CP
C-
INSTALLER
Fan
FAn
F-
INSTALLER
Alarms
ALL
A-
INSTALLER
Regulation
Re
b-
INSTALLER
Pump
PUP
P-
INSTALLER
Electric heater
Fro
r-
INSTALLER
Defrost
dFr
d-
INSTALLER
Electronic valve
EEu
U-
INSTALLER
Offset
OFF
o-
INSTALLER
Mixer valve
rAd
i-
INSTALLER
**Solar
SUn
S-
INSTALLER
Inverter
compressors
nCP
n-
INSTALLER
Hz massimi
LbH
L-
UTENTE/INSTALLATORE
* DHW preparer
AcS
Ac-
USER / INSTALLER
(*) Programmable parameters if the optional KIE module is present
5.4 SETPOINT ADJUSTABLE BY THE USER
SETPOINT
DESCRIZIONE
UNITA’
DEFAULT
RANGE
Coo
setpoint in Estate
°C
7.0
5÷18
Hea
setpoint in Inverno
°C
45.0
35÷57
*San
DHW mode setpoint
°C
48.0
25÷57
Co2
Secondo setpoint in Estate
°C
18.0
Coo÷23
He2
Secondo setpoint in Inverno
°C
35.0
25÷Hea
**rCO
Mixer valve setpoint in Summer mode
°C
15.0
-50.0÷80.0
**rHE
Mixer valve setpoint in Winter mode
°C
30.0
-50.0÷80.0
**ACS
DHW instantaneous production setpoint
°C
45.0
0.0÷80.0
(*)
Adjustable Setpoint if the DHW mode is active
(**)
Adjustable Setpoint if is intalled the optional KIE module
Setpoint type
Setpoint (summer/winter)
Summer default (range)
Winter default (range)
First setpoint (°C)
Coo/Hea
7 (5÷18)
45 (35÷55)
Second setpoint (°C)
Co2/He2
18 (7÷23)
35 (25÷45)
Sanitary Setpoint (°C)
San
48 (25÷55)
The functionality of the second setpoint can be used only when you purchase the proper optional kit.

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5.5 DISPLAY
In Normal view displays the outlet water temperature reported to tenths of degrees, or the alarm code if at least an alarm is
active. In case of multiple alarms activation, it will display the first alarm, while the second appears when the first is reset. Into the
menu mode, the display depends on the current position where you are.
5.6 LED
Compressor LED
ON if the compressor is running
OFF if the compressor is off
FLASHING if timings are in progress waiting for compressor’s start up
Sanitary water LED
ON if sanitary mode is active
OFF if the sanitary mode is not active
FLASHING if sanitary production in progress (sanitary valve is active)
Defrosting LED
ON in defrost operating mode
OFF if defrosting mode is disabled or completed
FLASHING if defrosting cycle interval’s time is in progress.
Antifreeze electric heater LED
The LED is ON if the antifreeze electric heater is active.
Water pump LED
The LED is ON if the water pump is running.
Alarm LED
The LED is ON if an alarm is activated.
Heat LED
The LED is ON if the unit is in the heating mode operation.
Cool LED
LED is ON if the unit is in the cooling mode operation.
5.7 INPUT/OUTPUT (I/O) PORTS
The I/O (inputs and outputs) that can be set to enable the control functions are listed below.
In order to set the I/O please enter with service password to the parameters PRGPSSPRG (insert the service password) 
PRG Par PRG CnF.
Ports
Parameter
Terminals
Factory Setting
Description
Value
Function
ST8
H19
SE/SE
0
Not set
Programmable analog input with NTC sensor
10kΏ at 25°C β 3435
ST9
H20
SAN/SAN
0
Not set
Programmable analog input with NTC sensor
10kΏ at 25°C β 3435
ID2
H39
ONOFF/ONOFF
2
Remote on/off
(See paragraph 10.5.1)
Voltage free contact digital input
ID3
H40
SW/SW
3
Remote summer/winter
commutation
(See paragraph 10.5.2)
Voltage free contact digital input
To activate this function see paragraph 10.5.2
ID7
H44
SE/SE
0
Not set
Voltage free contact digital input, programmable
instead of the analog input ST8 (H19=0)
ID8
H45
SAN/SAN
0
Not set
Voltage free contact digital input, programmable
instead of the analog input ST9 (H20=0)
DO3
H58
AEH (phase)
AEHN (neutral)
22
Command of the plant
auxiliary E-heater
(See paragraph 10.7.1)
Under voltage output single phase 230Vac, 50Hz,
5A resistive, 1A inductive.
To activate this function see paragraph 10.7.1
DO4
*H59
DO4 (phase)
DO4N (neutral)
0
Not set
Under voltage output single phase 230Vac, 50Hz,
5A resistive, 1A inductive.
DO5
*H60
DO5 (phase)
DO5N (neutral)
0
Not set
Under voltage output 230V ac, 50Hz, 5A
resistive, 1A inductive.
OC1
H61
NO1 (phase)
N1 (neutral)
NC1 (phase)
Command of DHW valve
(See paragraph 10.3)
Switching contact, single phase voltage 230Vac,
50Hz, 5A resistive, 1A inductive.
NO1= Normally open
NC1= Normally-Closed
To activate this function see paragraph 10.3
OC2
H62
NO2 (phase)
N2 (neutral)
NC2 (phase)
Command of Double
setpoint valve
(See paragraph 10.17)
Switching contact, single phase voltage 230 ac,
50Hz, 5A resistive, 1 A inductive.
NO2= Normally open
NC2= Normally-Closed
To activate this function see paragraph 10.17
(*) Do not change if the KA kit is installed is present

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Note: Note that with the adoption of the optional “KIE”module helps to increase the input/output (I/O) ports. For more
information, please refer to the related manual of this module.
6DYNAMIC SET-POINT ADJUSTMENT
The controller can change the set-point by adding a value depending on the outdoor air temperature sensor. In this case, you need
to change the values of the parameters from b08 to b14 following the indications below (the settings should be done by the
installer):
Parameters of the controller PAr->rE->
• b08 = dynamic set-point, enabled = 1/ unabled = 0.
•b09 = offset max in cooling mode operation.
• b10 = offset max in heating mode operation.
• b11 = Outdoor temperature setting in cooling mode.
• b12 = Outdoor temperature setting in heating mode.
• b13 = Temperature difference in cooling mode operation.
• b14 = Temperature difference in heating mode operation.
Curve of the set-point variation as a function of the outside temperature:
7SET-POINT ADJUSTMENT FROM 0-10V INPUT
Another type of setting that allows to change the set-point by adding (or subtracting) a value in function of the 0-10V analogue
input (if enabled). To enable the function, you must set the H21 parameter to be 40, and change the values of the parameter
b15 (range 0-10), taking into account that if b20=0 input of 0-10V, if b20=1 ratiometric input type:
-b20=0 if this input is at 0 volts you will have the actual set point: set point (Coo/Hea) - b15/2.
-b20=0 if the input is at 5 volts the set point will be the set of (Coo/Hea) mode.
-b20=0 if the input is 10 volts you will have the actual set point: set point (Coo/Hea) + b15/2.
Cooling
Heating

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-- b20=0 when the input is at 0%, the actual set point is: set point (Coo/Hea) - b15/2.
-- b20=0 when the input is at 50%, the set point will be the set of (Coo/Hea) mode.
-- b20=0 if the input is 100%, the actual set point is: set point (Coo/Hea) + b15/2.
The signal must be applied to the terminals 0-10V+ and 0-10V- (see the wiring diagrams).
Note: In "cooling" mode, considering that the set-point by default is set to be 7°C, the parameter (b15) should not assume any
value greater than or equal to 6 in order to prevent that the new set-point set from 0-10V input to take values below the threshold
of the antifreeze operation which is 4°C.
8CIRCULATOR
The circulating pump can be set according respecting the following operating modes:
-Thermoregulatory operation (default)
-Thermoregulatory operation with periodic activation
-Continuous operation
The circulator will switch off immediately if:
Presence of blocking pump alarm including the manual reset alarm of the flow switch;
The unit is off or in stand-by mode or when it’s switched off from remote input, the circulating pump (if is ON) will always
turn off after P02 (tenths of a minute):
The circulator is always running if the antifreeze heaters are activated.
The circulator can be configured with the parameter P03 in order to operate independently than the compressor or under call.
0=Continues operation
1=Operation under thermoregulatory call
Note: If the automatic reset alarm of the flow switch is active, the pump is anyway in operation even if the compressor is off.
Contrarily, the circulator remains always in operation if the antifreeze heaters are on or when the hydraulic pump operates in
antifreeze mode. The operation in antifreeze mode will start if the water setting temperature decreases below P04 °C (default
value 5°C), and it will be disabled if the water setting temperature increases above P04+P05 °C (the default value of P05 is 2,0°C).
The adjustment of the circulator is linear (see Paragraph 8.5).
8.1 OPERATION BY MEAN OF THERMOREGULATOR (Default)
During this operating mode (P03=1, default), the thermoregulator actuates the pump; after a time delay of P01 seconds from
startup of the pump, the compressor also will turn on. However, during the power off status, the pump turns off with a delay time
of P02 minutes after turning off status with thermoregulator call (the turning off status is corresponding to the off status of the
compressor).
In the case of activation of the flow switch alarms with automatic reset, the pump remains still in operation even if the compressor
is stopped.
If you enable the operation of the unit from the remote "on-off" digital input (see Paragraph 10.5.1) the circulating pump will be
activated immediately for a duration of 2 minutes regardless of the on-board controller thermoregulation of the unit (the
activation of water recirculation in the plant leads to a correct activation of the thermoregulation).

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8.2 OPERATION BY THERMOREGULATOR WITH PERIODIC ACTIVATION
The function is disabled if P17= 0 (default). If the pump is set to operate by thermoregulation call (P03 = 1, default), it will be
activated periodically for a time period defined by the parameter P17 (in seconds) after a counting time set by the parameter P16
(in minutes), activated when the pump is turned off for satisfied thermoregulation.
In the case of the activation of the flow switch alarm with automatic reset the pump is still operating even if the compressor is off.
The periodic function is also interrupted in the case of the intervention of the antifreeze thermo-regulator constraining the
operation of the pump.
8.3 OPERATION WITH ACTIVE ELECTRIC HEATER
See paragraph 10.9.
8.4 CONTINUOUS OPERATION
In this operating mode (enabled if P03=0), the pump is always running. It turns off only when the unit is in OFF status. The pump is
always ON even if automatic reset flow switch alarm is ON and even the compressor is off.
8.5 PROPORTIONAL ADJUSTMENT OF THE PUMP
The pump speed can change as a function of the temperature difference between the water inlet and the water outlet of the heat
exchanger, according to the diagram shown below, where:
P07: maximum speed of the modulating pump (%)
P08: minimum speed of the modulating pump (%)
P09: set Delta T inlet/outlet water of the modulating pump (°C)
P10: Delta modulating pump (°C)

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In domestic hot water production mode, the pump will operate at the maximum speed.
Note: If the parameter r33>0, then the circulator can start operations under call also for the activation of the plant resistance
and/or sanitary mode operation, see paragraph.Errore. L'origine riferimento non è stata trovata..
8.6 PURGING THE SYSTEM
This function allows purging the system using the circulator at the maximum speed.
To enable the function:
-Control in OFF mode
-Enter into the parameters PRGPSSPRG (introduce the Maintainer password)
-Press simultaneously for 3 seconds the buttons UP and DOWN.
The circulator of the system starts operation at the maximum speed, and after 5 minutes the circulator will stop to operate.
You can manually exit from purging the system cycle by pressing the MODE/ESC button, or by pressing simultaneously the UP and
DOWN buttons for 3 seconds.
During this function the flow switch alarm is deactivated.
9HEAT DISSIPATION FAN MOTOR CONTROL
The control of the dissipation is a function of the condensing pressure in chiller mode and it is a function of the evaporation
pressure in heat pump mode.
The adjustment of the fan speed occurs depending on the compressor operation.
9.1 FAN SPEED CONTROL IN COOLING MODE
The fan speed control in cooling mode occurs depending on the diagram shown below, where:
F08 = Pressure set to the minimum fan speed in cooling mode
F09 = Fan proportional band in cooling mode
F10 = Delta cut-off of the fan in heating/cooling mode
F11 = Cut-off hysteresis in cooling/heating mode
F14 = Pressure set to the maximum fan speed in cooling mode
Pre-ventilation period in chiller mode: before the compressor startup, the fan starts operation for 5 seconds; the fan speed is
proportional to the condensation temperature, however, if the controller requires the cut-off during this period, the fan motor will

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run at preset minimum fan speed. This function has the purpose to prevent the compressor startup at very high condensation
temperatures.
9.2 FAN SPEED CONTROL IN HEATING MODE
The fan speed control in heating mode occurs depending on the diagram shown below, where:
F17 = Pressure set for the minimum speed of the fan motor in heating mode
F18 = Fan motor proportional band in heating mode
F10 = Delta cut-off of the fan motor in cooling/heating mode
F11 = Cut-off hysteresis in cooling/heating mode
F20 = Pressure set for the maximum speed of the fan motor in heating mode
10 CONTROL FUNCTIONS
The functions that can be activated by the on-board unit controller are listed below, these functions are not all selectable at the
same time.
Other values different than the default can ensure the proper operation of the unit, in case of doubt about the value that to be set
please contact our office.
10.1 ALARM WARNING
You can configure an undervoltage output to warn the presence of an alarm.
In order to enable this function, you should enter into the page of parameters PRGPSS (insert the service password) PArCnF
I/O Ports - Parameter
Value
Function
Undervoltage output
24
Alarm notification
10.2 ANTIFREEZE PROTECTION ELECTRIC HEATERS (WHEN THE KA ACCESSORY IS PRESENT)
The electric heaters of water antifreeze, installed on the outer surfaces of the evaporator plates, activates even when the unit is
switched off (but energized) if the outlet water temperature goes below r02 °C (default is 4°C) in heating mode or below r03 °C
(default is 4°C) in cooling mode and in shut off condition. The same electric heaters are switched off when the temperature
measured by the outlet water sensor exceeds r02+r06 in heating mode or r03+r06 in cooling mode and in shut off condition (as
default value r06=2,0°C). The heating cable placed on the basement of the appliance turns on when the outdoor air temperature
decreases below 3°C and the unit starts the defrosting cycle (or if r19=0 even if the unit is not in defrosting cycle, or in stand-by
mode). It will be deactivated if the outdoor temperature exceeds 5°C or the last defrosting cycle is concluded after more than r19
minutes (default 10 minutes) (with r19≠0).
10.3 ACTIVATION OF SANITARY (DOMESTIC) HOT WATER PRODUCTION
To activate the hot sanitary water function, be sure to install a temperature sensor inside the tank and to connect it to the SAN-
SAN terminals (enabled as analog input).
In order to enable this function, you should enter into the page of parameters PRGPSSPRG(type the service password) 
PRGPArPRGCnF.
See paragraph 14.

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I/O Ports - Parameter
Value
Function
H10
0 (default)
Disenabled function
1
Function is active in heating and cooling mode.
The remote on-off function doesn’t disenable the DHW production.
2
Function is active in heating and cooling mode.
The remote on-off function disenables the DHW production.
3
Function is active in heating mode.
The remote on-off function doesn’t disenable the DHW production.
4
Active function in heating mode.
The remote on-off function disenables the DHW production.
5
Active function in cooling mode.
The remote on-off function doesn’t disenable the DHW production.
6
Active function in cooling mode.
The remote on-off function disenables the DHW production.
Analog input
6
Enablement of the DHW temperature sensor.
Undervoltage output
(OC1 by default)
6
DHW valve command
If the DHW temperature is below the set point value (set at 48°C by default and adjustable by entering the PRG->Set->SAN menu),
the unit activates the sanitary valve and the compressor is set at the maximum frequency starting the modulation at one degree
before the set value and it stops at one degree after the set value. Once reached the set point value, the valve switches to the
stand-by mode and the compressor works normally.
While shifting from user’s to domestic hot (sanitary) water, the operating sensor changes from “outlet water sensor” to “sanitary
tank sensor”. While shifting from the winter operating mode to the sanitary operating mode, the compressor does not switch off,
and reaches the maximum established frequency that to be controlled; on the other hand, while shifting from the summer
operating mode to the sanitary operating mode, the compressor is switched off to wait for the safety timing.
The defrosting during winter operation mode is always performed on the user side, never on the sanitary water tank.
Note:
-If H10 = 1. The remote turning off the unit (remote onoff see paragraph 10.5.1), or by the on board unit controller, or by a
remote control board does not affect the sanitary operating mode. The unit starts in sanitary mode as setting priority when it’s
powered on. The on board unit display shows the temperature measured by the sensor placed inside the sanitary water tank.
Once the sanitary cycle is completed, the display returns to show the temperature of the outlet water sensor.
If the remote ON-OFF digital input (onoff-onoff terminals) is open, with the enabling of the domestic hot water production (H10=1
and H20=6), the display on-board unit shows the item "SAN". Once the sanitary cycle is concluded, the display returns to show the
code "E00" indicating that the remote ON-OFF contact is open.
- If H10 = 2, the remote on-off function disenables the production of domestic hot water and the operations of the heat pump in
heating and cooling on plant side.
Example of activation of this function:
H10 =
1
H20 =
6

DHW temperature sensor [terminals: SAN –SAN]
H61 =
6(default)

In case of using a 3-way changeover valve with 3 contacts for power supply [terminals: NO1 –N - NC1]

In case of using a 3-way changeover valve with 2 contacts for power supply (with spring return),
[terminals: NO1 –N]
Closed contact NO1 means that the valve is energized and diverts the water flow to the DHW tank.
Open contact NO1 means that the valve is de-energized and diverts the water flow to users.
10.3.1SENSOR MEMORIZATION IN HEATING MODE
In the case of commutation from water users to the sanitary water, the temperature sensor changes from a "water outlet
temperature sensor" to a "water tank temperature sensor". For such reason, in heating mode, the last value read by the outlet
temperature sensor of the heat pump will be memorized before changing to sanitary mode.
When the sanitary thermoregulation is reached, the reference temperature on the plant side will take the value which is
previously memorized.
The memory function will be interrupted:
-When the temperature detected by the sensor becomes lower than the memorized value;
-Or after duration equal to b06 seconds (default 45 seconds).

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i-HWAK4
i-HWAK4
i-HWAK4
i-HWAK4
10.4 HEATING MODE ON SANITARY ACCUMULATION
If the parameter H83=1, the appliance exploits the accumulation tank for sanitary hot water also to heat the plant side. In these
conditions, the relay which controls the sanitary valve will be also energized during heating operation and not only in sanitary
mode. During defrost cycle and in cooling mode the valve will be de-energized. When H83=1, the sanitary auxiliary electric heater
can be enabled also to act as a plant auxiliary electric heater: to this purpose you should set r10=1 and r15=2 (for further settings
of the parameter r15 please see Paragraph 10.7.3); also no digital output has to be set for the auxiliary electric heater for the
plant.

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10.5 REMOTE FUNCTIONS
The terminal block provides the digital inputs to control the unit via an external consent.
10.5.1ON/OFF
The ON/OFF function is enabled by default on the digital input “ID2” (terminals: ON/OFF-ON/OFF). Remove the bridge of the
terminal block then the unit will be placed in stand-by mode (in such status the display of the on-board unit controller will show
the "E00" item). When the contact is closed, the machine exits from standby mode and the circulation pump will be activated for 2
minutes.
Enabled function by default (H39 parameter, ON/OFF reference terminal)
I/O Ports - Parameter
Value
Function
Digital input (ID2 by default)
2
Enablement of the remote On/Off function
If the sanitary mode is active and the H10 parameter is set as:
H10 = 1. The remote on-off function has no effect on the production of domestic hot water, it turns off only the
heating/cooling operation of the heat pump on plant side (in such case the on-board unit control display shows the item "SAN").
H10 = 2, the on-off remote function turns off the production of domestic hot water and the heating/cooling operating of
the heat pump on plant side.
10.5.2SUMMER/WINTER MODE COMMUTATION
This function is set by default on the digital input ID3 (terminals: ON/OFF-ON/OFF). To activate this function please set the
parameter H76 to be 1 (H76=1).
You can manage remotely the operating mode in heating or in cooling of the heat pump.
In order to enable this function, you should enter into parameters PRGPSSPRG(insert the service password)PRGPar
PRGCnF.
I/O Ports - Parameter
Value
Function
H76
1
Enables the remote summer/winter commutation function
Digital input
(ID3 set by default)
3
Open Contact Heat pump in heating mode.
Closed Contact The heat pump in cooling mode.
10.5.3 SANITARY MODE CALL FROM DIGITAL INPUT
If the domestic hot water mode operation is enabled and the parameter used as alternative of the temperature sensor, the
activation of the domestic hot water operation can be performed through the opening/closing of a digital input of the unit. This
function is recommended in the case of utilization of two or more minichillers in cascade configuration and linked through a
hydronic connection to the same accumulation tank of domestic hot water; in this way the activation of the domestic hot water
function will be selected through the sensor of the accumulation tank connected to the first unit, while the other units will be
automatically enabled by a digital consent.
The system goes in domestic hot water mode when the digital input closes and quits this mode when the digital input opens.
In order to enable this function, you should enter into the page of parameters PRGPSSPRG (insert the service password) 
PRG PAr PRG CnF.
I/O Ports - Parameter
Value
Function
H54
128
Digital inputs polarity
Digital input
(activable on ID8)
28
Closed contact Heat pump in DHW mode.
Open contact Heat pump in heating or cooling mode of
the environment (plant system mode).
-In the case where a digital input is configured for DHW function call (instead of the sensor), the heat pump starts will be
placed in DHW mode when the digital input is closed and exits from the DHW production when the digital input is open.
-The SAN setpoint of the heat pump is not considered, the management of such setpoint is entrusted to the designer of the
plant, who must take into account the domestic hot water protection and the configuration of the whole system.
Note:
-You can reverse the polarity of the digital input, placing the maintainer (service) parameter to be H54 = 0.
Example of activation of the functions:
H10 =
1
H45 =
28

Digital input [terminals: SAN –SAN]
Closed contact Heat pump in sanitary mode.
Open contact Heat pump in plant mode.
H54 =
128
H61 =
6(default)

In case of using a 3-way changeover valve with 3 contacts for power supply [terminals: NO1 –N - NC1]

In case of using a 3-way changeover valve with 2 contacts for power supply (with spring return),
[terminals: NO1 –N]

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10.6 REMOTE SENSOR FOR THE WATER TEMPERATURE OF THE PLANT CIRCUIT
In some configurations of systems (example: heat pump in parallel with a boiler on the same hydronic circuit and diverter valve of
exclusion) it could be necessary to enable a plant temperature sensor to allow the on-board unit controller to correctly process
the management.
In order to enable this function, please enter into the page of parameters PRGPSSPRG (insert the service password) 
PRG PAr PRG CnF.
I/O Ports - Parameter
Value
Description
Analog input
(activable on ST8)
41
Enablement of the plant circuit remote temperature sensor
The plant circuit remote sensor adjusts the heat pump temperature only during the startup period of the compressor(s), the
shutdown is managed by the outlet temperature sensor of the heat pump. For more explanation herein below is reported an
illustrating table regarding the operation of the system:
Operating mode
Enablement of the heat pump call
Heating
Temperature measured by outlet sensor of the heat pump < setpoint Hea - b05
and
Temperature measured by plant circuit remote sensor < water setpoint Hea - (b22 - b05)
Cooling
Temperature measured by the outlet sensor of the heat pump > setpoint Coo + b05
and
Temperature measured by plant circuit remote sensor > setpoint Coo + (b22 - b05)
Note: b05=1°C; b22=5°C. See paragraph 14.
10.7 AUXILIARY ELECTRIC HEATER
In some configurations of some plant systems, it could be necessary the use an auxiliary electric heater for the system and/or
DHW sides.
To define the mode of using of the auxiliary electric heaters for plant system and DHW side, you must set the parameter “r24”as
below.
-r24=0 Auxiliary electric heaters not used;
-r24=1 Utilization only of the auxiliary electric heater of the plant side;
-r24=2 Utilization only of the auxiliary DHW electric heater;
-r24=3 Utilization of both auxiliary electric heaters of plant side and of domestic (sanitary) hot water production.
10.7.1PLANT CIRCUIT ELECTRIC HEATER
If the temperature of regulation remains below the water setpoint in heating (Hea) - 0.5°C for a period of time equal to r12, the
auxiliary electric heater will be activated depending on the in joint or in substitution operation of the unit indicated in Paragraph
10.12.
The electric heater turns off after reaching the setpoint (taking into account of an eventual offset set with the parameters r29 or
r30.
If the temperature of regulation remains less than water setpoint - r11(°C) and the unit is blocked that is caused by an error-
alarm, the electric heater will be activated. Then it will turn off when the lock-alarm is resolved.
In order to enable this function, you should enter into the page of parameters as follow PRGPSSPRG (insert the service
password) PRG PAr PRG CnF / Fro.
I/O Ports - Parameter
Value
Function
r10
1
Enablement of the function
r11
0.5°C (default)
Delta of the auxiliary electric heaters in heating operation
r12
10 minutes (default)
Activation delay of auxiliary heating element of the plant side
r24
1 or 3
Type of utilization of the electric heater
Undervoltage output
(DO3 by default)
22
Plant auxiliary electric heater
10.7.2AUXILIARY ELECTRIC HEATER OF THE PLANT IN DEFROST CYCLE
During defrost cycle (see Paragraph 10.14), by setting r21=1 (in addition to r10=1 and r24=1 or 3) the electric heater of the plant
system side will be activated if required (regulating temperature lower than the water setpoint - r11 (°C)), without waiting for the
time defined by r12.
In order to enable this function, please enter into the page of parameters as follow PRGPSSPRG (then insert the service
password) PRG PAr PRG Fro.

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10.7.3ELECTRIC HEATER OF SANITARY WATER PRODUCTION
It is an additional energy resource for the sanitary water tank heating when the compressor is not able to reach the set
temperature within a reasonable time.
If the production of sanitary hot water lasts for a period of time greater than r16 (minutes) and the unit gets blocked due to an
alarm intervention, the electric heater will be enabled. It turns off when the unit concludes the sanitary water production (taking
into account also of any offset set by the parameters r31 as described in the Paragraph 10.12.1.)
In order to enable this function, please enter into the page of parameters PRGPSSPRG (insert the service password) 
PRG PAr PRG Fro.
I/O Ports - Parameter
Value
Function
r15
1
Enablement of the function
r16
10 minutes
(default)
Activation delay of the auxiliary DHW heating element
r24
2 o 3
Type of electric heaters utilization
Undervoltage output
26
Plant side auxiliary electric heater
Note: The DHW function must be active (see paragraph 10.3)
10.7.4A UNIQUE AUXILIARY ELECTRIC HEATER FOR BOTH PLANT SYSTEM/DHW PRODUCTION
By configuring the auxiliary electric heater for DHW production, you can use such declared electric heater, also as an auxiliary
electric heater for the plant system by selecting the following setting r15=2 and r24=3.
When the auxiliary electric heater of the plant system is activated, the declared DHW electric heater will be activated allowing you
to get one auxiliary electric heater for DHW production, plant system and defrosting operation.
In order to enable the function, you should enter into the page of parameters as follow: PRGPSSPRG (then insert the
service password) PRG PAr PRG Fro.
10.8 SELECTION MODE OF AUXILIRY ELECTRIC HEATERS
It is possible to set the order priority of the activation of the of the plant system and of the DHW production sides auxiliary electric
heaters as in the below configurations:
r14=0 (default), the electric heaters will be activated simultaneously if they are present;
r14=1, the electric heaters will be activated one excludes the other:
r20=0, the priority is for the plant (the sanitary heater will operate only if the thermoregulation for the heater of
plant side is accomplished);
r20=1, the priority is for the sanitary (the electric heater of the plant system side will operate only if the
thermoregulation of the sanitary heater is accomplished).
10.9 MANAGEMENT OF THE CIRCULATOR WITH ACTIVE ELECTRIC HEATER
It is possible to activate the circulator of the heat pump when the plant system and/or the DHW auxiliary electric heaters are
active in the absence of compressors operations (for substitution, for alarm or for integration in band II or III).
For enabling this function, you should enter into the parameters as follow: press PRGPSSPRG (then insert the service
password) PRG PAr PRG Fro:
r33 = 0: The circulator of the heat pump will be activated upon request of the compressors or by the boiler.
r33 = 1: The circulator of the heat pump will be activated if the plant circuit electric heater is active.
r33 = 2: The circulator of the heat pump will be activated if the DHW electric heater is active.
r33 = 3: The circulator of the heat pump will be activated if the plant system electric heater or if the DHW electric heater is
active.
The circulator will stop operation after the post-pumping (P02).
10.10BOILER ENABLEMENT
It is an additional resource that enables the boiler in integration or in substitution of the heat pump.
For enabling this function, you should enter into the parameters as follow: press PRGPSSPRG(then insert the service
password)PRGPArPRGCnF/Fro:
Definition of the type of using of the auxiliary systems by setting the parameter r23:
-r23=0 (default) boiler not used (priority of intervention is for electric heaters);
-r23=1 boiler used just on plant side (priority of intervention is for electric heaters);
-r23=2 boiler used just for DHW hot water (priority of intervention is for electric heaters);
-r23=3 (default) boiler used for both DHW hot water and plant sides (priority of intervention is for electric heaters);
-r23=4 boiler used only for plant side with priority (no intervention priority for electric heaters);
-r23=5 boiler used only for DHW hot water with priority (no intervention priority for electric heaters);
-r23=6 boiler used on both DHW and plant sides with priority (no intervention priority for electric heaters);
Settings of the parameter r32 for boiler equipment:

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-r32 = 0: boiler without a circulating pump with thermoregulation to be performed by the heat pump unit.
-r32 = 1: boiler equipped with independent circulating pump with thermoregulation to be performed by the heat pump unit.
-r32 = 2: boiler without circulating pump with independent thermoregulation.
-r32 = 3: boiler equipped with a circulating pump with independent thermoregulation.
I/O Ports - Parameter
Value
Function
r23
1/2/3/4/5/6
Type of boiler utilization
r32
1/2/3
Boiler Endowment
Under voltage output
29
Enablement of boiler
10.11ACTIVATION OF AUXILIARY ELECTRIC HEATERS AND BOILER DURING THE JOINT AND IN
SUBSTITUTION OPERATION TO THE COMPRESSOR OF THE HEAT PUMP
The available auxiliary systems for the joint operation or substitution operation are as below:
- Boiler
- Plant auxiliary electric heater
-DHW (Sanitary) auxiliary electric heater
Considering the heating and sanitary mode of operation, you have 4 types of operation:
Heat pump
Tout .[°C]
r22=7
r28=-7
r08=-20
0Heat pump + [Boiler and/or electricheater]
[Boiler and/or electricheater]
Boiler + [Heat pump and/or electricheater]
IN JOINT OPERATION I
IN JOINT OPERATION II
IN SUBSTITUTION OPERATION
When changing the values of the parameters r22, r28, r08, you have to respect the following condition: r22 ≥ r28 ≥ r08.
You can remove the zone corresponding to the “in joint operation I”just by putting r22=r28; you can also remove the zone
corresponding to the “in joint operation II”by putting r28=r08; and hence you can remove both “in joint operations I and II”just
by setting the three parameters as the following configuration r22=r28=r08.
10.11.1 OPERATION IN HEAT PUMP MODE
Normal operation of the heat pump in which the electric heaters and-or the boiler will be activated only if the heat pump goes
into error-alarm.
10.11.2 IN JOINT OPERATION (AREA I)
If the outdoor air temperature is included between r22 and r28, the compressor operates in synergy with the auxiliary electric
heaters during winter and domestic hot water mode.
In this operation area, the heat pump will start at the beginning and then the plant side auxiliary electric heaters will operate after
a period of time given by r12 (in minutes) and after r16 (in minutes) the DHW auxiliary electric heaters will start operation.
The activation priorities are defined by the parameters r14, r20, r23 and r24.
The operation becomes normal if the temperature increases above the value given by r22 + 1,0°C.
Note: In the joint operation, the temperature of the boiler is controlled by the water temperature remote sensor of the plant
circuit (if enabled), particularly if the temperature measured by the remote sensor is less than the setpoint Hea, the boiler will be
activated, and then will be deactivated when the measured temperature by the remote sensor is greater than setpoint Hea. The
heat pump follows the activation logic described in paragraph 10.6.
The boiler will be managed by the outlet temperature sensor of the heat pump if the water plant circuit remote sensor is not
enabled.
10.11.3 IN JOINT OPERATION (AREA II)
If the outdoor air temperature is included between r28 and r08, the compressor will operate in synergy with the auxiliary electric
heaters.
In this operation area, the devices will start operation in the following working order: at first the boiler will start the operation,
then the heat pump and the plant circuit auxiliary electric heaters will start operation after a period of time given by r12 (in
minutes) and after r16 (in minutes) the DHW auxiliary electric heaters will start operation.
The activation priorities are defined by the following parameters r14, r20, r23 and r24.
The operation becomes normal if the temperature increases above the value of r28+1,0°C.
Note: In the joint operation, the temperature of the boiler is adjusted by the water temperature remote sensor of the plant circuit
(if enabled), particularly if the temperature measured by this remote sensor is less than the setpoint Hea, the boiler will be

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activated, and then will be deactivated when the measured temperature by the remote sensor is greater than setpoint Hea. The
heat pump follows the activation logic described in paragraph 10.6.
The boiler will be managed by the outlet temperature sensor of the heat pump if the water plant circuit remote sensor is not
active.
10.11.4 IN SUBSTITUTION OPERATION
If the outdoor air temperature decreases below r08,the compressor operation will be inhibited.
If the auxiliary system is composed of the plant circuit and/or the DHW electric heaters, they will be activated in substitution
to the compressor with a duration defined by r12 (minutes) for the plant circuit side and by r16 (minutes) for the domestic
hot water side.
During the substitution operation, instead it is not necessary to enable the auxiliary electric heaters with the parameter r10
or r15, because the auxiliary electric heaters operate in substitution (and not as auxiliary heating systems) to the heat pump
(therefore it is enough to select the type of utilization of the auxiliary electric heaters by setting only the parameter r24).
If the auxiliary system is a boiler with its proper circulator (r32 = 1or 3).
The circulator of the heat pump will be off, the boiler will be enabled after P01 (default 30 seconds).
Note: When the defrosting protection occurs on the water side, the utilization pump will be activated (or remains on).
If the in substitution auxiliary system is a boiler with its proper temperature control (r32 = 2or 3).
The boiler will be enabled independently than thermoregulation of the heat pump.
If the in substitution auxiliary system is a boiler without circulator (r32 = 0or 2).
The circulator of the heat pump will be active when the boiler is enabled.
The compressor will be enabled again if the temperature increases above the value of r08+r09 (°C) (by default r09=1,0 °C)
10.12OPERATION AREA - ACTIVATION OF THE AUXILIARY ELECTRIC HEATER AND BOILER (Plant circuit
water temperature sensor is not enabled)
The possible configurations of the parameters related to auxiliary heaters are listed below in the tables 1, 2, 3 and 4, that are
divided by areas of operation (the columns of the items "MODE" and "rxx" parameters indicate the operation mode and the
possible values of the parameters for allowing the auxiliary electric heaters to act according to a predefined order of intervention,
when the unit is running in a certain type of operation; several modes and values of the parameters can be alternatively selected
and they are reported in the same cell separated by the symbol "/").
TABLE 1. NORMAL OPERATION IN HEAT PUMP MODE
N°
ORDER OF INTERVENTION OF
HEATING SYSTEMS (when the set-
point is not achieved and the unit
is in alarm condition)
MODE
OPERATION
r10
r15
r12
r16
r23
r24
1
1) Auxiliary electric heater of plant
HEAT /
HEAT+SAN
HEAT
1
0/1/2
/
/
0/2/5
1/3
2
1) Boiler
HEAT /
HEAT+SAN
HEAT
0/1
0/1/2
/
/
1/3/4/6
0/2
3
1) Auxiliary electric heater of plant
2) After r12 minutes, Boiler
HEAT /
HEAT+SAN
HEAT
1
0/1/2
Set up of
minutes
/
1/3
1/3
4
1) Boiler
2) After r12 minutes, auxiliary
electric heater of plant
HEAT /
HEAT+SAN
HEAT
1
0/1/2
Set up of
minutes
/
4/6
1/3
5
1) Auxiliary electric heater of sanitary
HEAT+SAN
SANITARY
0/1
1
/
/
0/1/4
2/3
6
1) Boiler
HEAT+SAN/
COOL+SAN
SANITARY
0/1
0/1/2
/
/
2/3/5/6
0/1
7
1) Auxiliary electric heater of
sanitary
2) After r15 minutes, boiler
HEAT+SAN
SANITARY
0/1
1
/
Set up of
minutes
2/3
2/3
8
1) Boiler
2) After r15 minutes, auxiliary
electric heater of sanitary
HEAT+SAN
SANITARY
0/1
1
/
Set up of
minutes
5/6
2/3
9
1) Auxiliary electric heater of
Plant/sanitary
HEAT /
HEAT+SAN
IN HEAT OR IN
SANITARY
1
1
/
/
0
3
10
1) Boiler
HEAT /
HEAT+SAN
IN HEAT OR IN
SANITARY
0/1
0/1/2
/
/
3/6
0
11
1) Auxiliary electric heater of
plant/sanitary
2) After r12 minutes, Boiler
HEAT /
HEAT+SAN
IN HEAT OR IN
SANITARY
1
1
Set up of
minutes
Set up of
minutes
3
3
12
1) Boiler
2) After r12 minutes, auxiliary
electric heater of plant/sanitary
HEAT /
HEAT+SAN
IN HEAT OR IN
SANITARY
1
1
Set up of
minutes
Set up of
minutes
6
3