HIdRos ITMBT Series User manual

1
LOW TEMPERATURE DEHUMIDIFIERS
ITMBT
SERIES
TECHNICAL MANUAL

ITMBT Low temperature dehumidifiers
MTITMBTGB REV.112008
2

ITMBT Low temperature dehumidifiers
MTITMBTGB REV.112008
3

ITMBT Low temperature dehumidifiers
MTITMBTGB REV.112008
4

ITMBT Low temperature dehumidifiers
MTITMBTGB REV.112008
5
INDEX
Declaration of conformity page 3
Aim and contents of this manual page 6
How to keep this manual page 6
Graphyc symbols page 6
Safety laws page 7
General safety guidelines page 7
Worker’s health and safety page 8
Protective equipment page 8
Safety signs page 8
Unit description page 9
Other versions page 10
Accessories page 10
Technical Data page 11
Operation limits page 12
Sound data page 12
Safety device page 13
Safety device setting page 13
Electrical data page 13
Inspection page 14
Lifting and handling page 14
Location and minimum technical clearances page 14
Condensate draining connections page 15
Ductwork unit connection page 16
Refrigerant connections for Z versions page 17
Refrigerant lay-out page 18
Electrical connections page 19
Start-up page 19
Control panel page 20
Unit switch off page 21
Energy saving page 22
Maintenance and periodic checks page 22
Refrigerant circuit repair page 22
Environment protection page 22
Unit out of service page 22
Unit alarm page 23
Fault finding page 23
Wiring diagrams page 24
Dimensions page 36

ITMBT Low temperature dehumidifiers
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The ITMBT manual, contains any information that is needed for a correct use of the equipment while safeguarding operator safety ,
according to what indicated in the actual directives on units safety.
AIM AND CONTENTS OF THIS MANUAL
This manual provides basic information on the installation, operation and maintenance of the ITM BT unit. 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.
This manual describes the characteristics of the equipment at the time it is being put on the market; therefore it may not capture later
technological improvements introduced by HIDROS SRL as part of its constant endeavour to enhance the performance, ergonomics,
safety and functionality of its products.
HOW TO KEEP THIS MANUAL
The manual must be always wit h the unit it refers to. It must be stored in a safe place, away from the dust and moisture. It must be
accessible to all users who shall consult it any time they are in doubt on how to operate the equipment.
HIDROS SRL reserves the righ t to modify it s products and related manuals with out necessarily updating previous versions of the
reference material. The customer shall store any updated copy of the manual or parts of it delivered by the manufacturer as an
attachment to this manual.
HIDROS SRL is available to g ive any detailed information about this manual a nd to give information regarding the use and the
maintenance of its own units.
GRAPHIC SYMBOLS
Indicates operations that can be dangerous for people and/ordisrupts the correct operation of the
equipment..
Indicates prohibited operations.
Indicates important information that the operator must follow in order to guarantee the correct operation
of the equipment in complete safety

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SAFETY LAWS
The units single components or the complete units produced by HIDROS have been designed according to the actual CE and
national Directives. For the detailed list of the project technical Directives, refer to the CE declaration enclosed.
GENERAL SAFETY GUIDELINES
Before beginning to operate on ITMBT units every user must be perfectly knowledgeable about the functions of the equipment and
its controls and must have read and understood the information container in this manual.
It’s strictly forbidden to remove and/or camper with any safety device.
Any routine or not-routine maintenance operation shall be carried out when the equipment has been shut
down, disconnected from electric and pneumatic power source and after its pneumatic system has been
discharged.
Do not put your hands or insert screwdrivers, spanners or other tools into moving parts of the equipment.
The equipment supervisor and the maintenance man must receive training suitable for the performance of
their tasks in safety
Operators must know how to use personal protective devices and must know the accident-prevention
guidelines contained in national and international laws and norms.

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WORKERS’ HEALTH AND SAFETY
The European Community has emanated some Directives about worker’s safety and health which the employers have to respect
and make the others respect. For the detailed list, see the CE declaration enclosed.
Do not tamper with or replace parts of the equipment without the specific consent of the manufacturer.
The manufacturer shall have no responsibility whatsoever in case of unauthorised operations.
Using components, expendable materials or spare parts that do not correspond to those recommended
by the manufacturer and/or listed in this manual may be dangerous for the operators and/ordamage the
equipment
The operator’s workplace must be kept clean, tidy and free from objects that may camper 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 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...
PERSONAL PROTECTIVE EQUIPMENT
When operating and maintaining the ITMBT unit, use the following personal protective equipment.
Equipment: people who make maintenance or work with the unit, must wear an equipment in accordance
with the safety Directives. They must wear accident prevention shoes with anti-slip sole where the paving
is slippery.
Gloves: During the cleanings and the maintenance operations, it’s necessary the use of appropriate
gloves. In case of gas recharge, it’s compulsory the use of appropriate gloves to avoid the risk of
freezing.
Mask and googles: Respiratory protection (mask) and eye protection (goggles) should be
used during cleaning and maintenance operations.
SAFETY SIGNS
The equipment features the following safety signs, which must be complied with:
General hazard
Electric shock hazard

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UNIT DESCRIPTION
ITMBT low temp erature dehumidifiers series are high performances units especially designed for cold room applications where th e
humidity level should be controlled during pr oduct storage treatment. All units are s upplied with hot gas defrost system and
antifreeze heater on condensate drip tray.
Frame
All ITMBT units are made from hot-galvanised thick sheet meta l, painted with po lyurethane powder enamel at 180°C to ensure the
best resistan ce against the atm ospheric agents. The frame is self-supporting with removable panels. The drip tray is present
standard in all ITMBT units and it’s in stainless steel. The colour of the units is RAL 7035
Refrigerant circuit
The refrigerant gas used in the se units is R407C. The ref rigerant circuit is mad e by using international primary brands compone nts
and according to ISO 97/23 concerning welding procedures. The refrigerant circuit includes:
sight glass,
filter drier,
thermal expansion valve with external equalizer,
Schrader valves form maintenance and control,
pressure safety device (according to PED regulation),
Solenoid valve for hot gas defrost injection,
Antifreeze electric heater mounted in the condensate drip tray.
Compressors
The compressor is scroll type with crankcase heater and thermal overload protection by a klixon embedded in the motor winding. It’s
mounted on rub ber vibration dampers and, by request, it can b e supplied with some jackets to reduce the noise (accessory). The
crankcase heate r, when present, is always powered when the c ompressor is in stand-by. The in spection is possible through the
frontal panel of the unit.
Condensers and evaporators
The condensers and evaporators are made of copper pipes and aluminiu m fins. The diameter o f the copper pipes is 3/8” and t he
thickness of the aluminium fins is 0 ,1 mm. The tubes are me chanically expa nded into the aluminium fin s to improve the h eat
exchange factor. The geometry of these conden sers guarantees a lo w air side pressure drop and then the use of low rotation (and
low noise emission) fans. All the units have a stainless steel drip tray. Besides t his, each evaporator is supplied of a temper ature
probe used as automatic antifreeze probe.
Fans
The fan is centrifugal type. It’s st atically and dynamically balanced and supp lied complete of the safety fan guard according t o EN
294. It’s mounted on the unit fra me by interposition of rubbe r vibration dampers. The electric motor is at 4 poles (about 1500 rpm).
Connected to the fan by belts and pulleys and it’s equipped of an integrated thermal overload protection. The protection class of the
motors is IP 54.
Air Filter
It’s supplied standard with the unit. It’s made of filtering materi al in synthetic fibre without electrostatic charge. It can b e removed for
differential disposal, class G3, according to EN 779:2002
Electric box
The electric switch board is mad e according to e lectromagnetic compatibility norms CEE 73/23 a nd 89/336. The accessibi lity to the
board is possible after removing the front panel of the unit and t he OFF positioning of the ma in switch. The moisture protection
degree is IP55. In all ITMBT units are installe d, standard, t he compressors sequence relay who disables th e operation of the
compressor in case the power supply phase sequence is not the correct one (scroll compressor s in fact, can be damaged if the y
rotate reverse wise). The following components are also standard installed: main switch, magnetic-thermal switches (as a protection
of pumps and f ans), compressors fuses, contr ol circuit automatic breakers, compressor contactors. The terminal board is also
supplied with voltage free contacts for remote ON-OFF.
Microprocessors
All ITMBT units are supplied standard with microprocessor controls. The microprocessor controls the following functions: compressor
timing, automatic defrost cycles, alarms. An appropriate LCD display shows the operation mode of the unit, set point and alarms.

ITMBT Low temperature dehumidifiers
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Control and protection devices
All units are supplied with the following control and protection devices: defrost thermostat, who signals to the microprocessor control
that a defrost c ycle is needed and controls its termination, high pressure swi tch with manual reset, low p ressure switch with
automatic reset, high pressure safety valve, compressor thermal overload protection, fans thermal overload protection
Test
All the units are fully assembled and wired at th e factory, ca refully evacuated an d dried after leak tests under pressure and t hen
charged with refrigerant R407C. They are all fully operational test ed before shipment. T hey all conform to European Directives and
are individually marked with the CE label and provided with Conformity Declaration
OTHER VERSIONS
TEMPERATURE CONTROL VERSION (ITMBTZ): These unit s are equipped of an external remote condenser and needs to be
connected to the dehumidifier through refrigerant connections. The remote condenser is supplied, standard, of a main switch and a
fan speed controller. The use of the remote condenser allows the control of temperature and humidity at the same time, operating in
cooling or dehu midifying mode. All the unit s of ITMBTZ series , to work correct ly, have to be connected to a thermostat and a
humidistat.
Remote condenser (Only for ITMZ/BT versions)
The remote condensers are made of copper pipes and aluminium fins. The diameter of the copper pipes is 3/8” and the thickness of
the aluminium fins is 0,1 mm. The tubes are mechanically expanded into the aluminium fins to improve the heat exchange factor.
The geometry of these condensers guarantees a low air side pressure drop and then the use of low rotation (and low noise
emission) fans. The fans are axial type with aluminium aerofoil blades complete of the safety fan guard. The protection class of the
motors is IP 54. Furthermore the remote condenser is supplied of the low ambient condensing pressure control. This device controls
the cooling circuit condensing pressure at different ambient temperatures, to keep it correct.
ACCESSORIES
Built-in or remote mechanical hygrostat: supplied with a regulation kno b and working range from 30 % to 100 % wit h
precision of 3%.
Available static pressure: with high efficiency fan; available up to 200 pa.
Air filter with ducted installation: Complete with EU2 efficiency air filter which can be removed by the side and frame
for ducted installation.
Floor trolley version: To be used with movable applications. They are not available for ITMBTZ versions.

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TECHNICAL DATA
Mod. 330 330Z 400 400Z
Refrigerant R407C R407C R407C R407C
Dehumidification capacity (1) l/24h 155,8 155, 8 189, 8 414,8
Cooling capacity (2) kW --- 10,1 --- 12,4
Compressor input power (1) kW 5,3 6,0 6,6 6,6
Maximum input power (1) kW 7,0 7,4 8,0 7,9
Nominal input current (1) A 16,0 18,0 17,6 19
Maximum input current A 18,5 20,0 24,0 19,7
Power supply V/Ph/Hz 400/3+N/50
Total air flow m3/s 1,055 1,055 1,111 1,111
Supply fan available static pressure Pa 50 50 50 50
Compressor tipo SCROLL
n° 1 1 1 1
Refrigerants circuits n° 1 1 1 1
Capacity steps 1 1 1 1
Sound power level (5) dB(A) 73 73 75 75
Sound pressure level (6) dB(A) 66 66 68 68
Length mm 1004 1 004 1 004 1004
Width mm 635 635 635 635
Height mm 1283 1 283 1 283 1283
Weight Kg 184 184 188 188
TECHNICAL DATA REMOTE CONDENSERS
Mod. 330 330Z 400 400Z
Refrigerant --- R407C --- R407C
Maximum input current A --- 5,0 --- 5,0
Power supply V/Ph/Hz 230/1/50
Total air flow m3/s --- 3,2 --- 3,2
Sound power level (5) dB(A) --- 73 --- 73
Sound pressure level (7) dB(A) --- 45 --- 45
Length mm 1292 --- 1292
Width mm 480 --- 480
Height mm 610 --- 610
Weight Kg 45 --- 45
Performances are referred to the following conditions:
(1 Ambient temperature 30 °C relative humidity 80%;
(2) Ambient temperature 30 °C relative humidity 80%; ambient temperature 35°C.
(5) Sound power level calculated according to ISO 3746.
(6) Sound pressure level measured in free field, at 1 mt from the unit, directional factor Q=2 according to ISO 3746.
(7 Sound pressure level measured in free field, at 10 mt from the unit, directional factor Q=2 according to ISO 3746

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OPERATION LIMITS
Relative humidity (%)
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
-10 0 10 20 30 40
Room temperature (°C)
Ambient temperatures
ITMBT units are designed to operate with ambient temperatures from 1°C to 18°C, relative humidity from 50% to 99%
WARNING: The units MUST be used within the operation limit indicated in the diagrams (see above). the
warranty will be invalidated if the units are used in ambient conditions outside the limits reported. If there
is the necessity to operate in different conditions, please contact our technical office.
SOUND DATA INTERNAL UNIT
Mod. Octave band (Hz) Lw Lp1 63 125 250 500 1K 2K 4K 8K dB dB(A) dB(A)
dB dB dB dB dB dB dB dB
330 86,1 77,3 71,2 69,7 68,6 63,2 59,8 50,7 86,9 73 66
400 88,1 79,3 73,2 71,7 70,6 65,2 61,8 52,7 88,9 75 68
330Z 86,1 77,3 71,2 69,7 68,6 63,2 59,8 50,7 86,9 73 66
400Z 88,1 79,3 73,2 71,7 70,6 65,2 61,8 52,7 88,9 75 68
SOUND DATA EXTERNAL UNIT (ONLY FOR Z VERSION)
Mod. Octave band (Hz) Lw Lp2 63 125 250 500 1K 2K 4K 8K dB dB(A) dB(A)
dB dB dB dB dB dB dB dB
330Z 86,1 77,3 71,2 69,7 68,6 63,2 59,8 50,7 86,9 73 45
400Z 86,1 77,3 71,2 69,7 68,6 63,2 59,8 50,7 86,9 73 45
Lw: Sound power level according to ISO 3746.
Lp1: Sound pressure level measured at 1 mt from the unit in free field conditions direction factor Q=2 according to ISO 3746.
Lp2: Sound pressure level measured at 10 mt from the unit in free field conditions direction factor Q=2 according to ISO 3746.
Standard
operation
99%

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SAFETY DEVICE
The frost on the coil, obstructs t he air flow, redu ces the available exchange area and conseque ntly the unit performances and c an
seriously damage the system. All the unit s are supplied, standar d, with a control which defrost a utomatically the heat exchanger if
necessary. This control provides a temperature probe (defrost thermostat) on the unit evaporator. When the defrost cycle is required,
the microprocessor control (according to set parameters) starts working (the yellow led turns on) according to these modalities:
- hot gas defrost: the fan is switched off while the compressor keeps on wo rking. An appropriate switching on the refrigerant syste m
is activated.
For both the modalities, at the end of the defrost cycle, there is the dripping time (the green led starts flashing)
HYGROSTAT
The hygrostat enables or disables unit operation depending on the humidity value desired.
To verify its correct operation, rotate t he control knob clock wise (or set the de sired value t hrough the instrum ent keyboard i f a
keyboard instru ment should be present) and set the humidity desired value close to lower lim it. At this point verify that fan a nd
compressor (after a time delay) will be started in sequence. Verify as well that the unit is stopped when humidity set is reached
THERMOSTAT (Z versions only)
The thermostat enables or disables unit operation depending on the temperature value desired.
To verify its correct operation, rotate t he control knob clock wise (or set the de sired value t hrough the instrum ent keyboard i f a
keyboard instrument should be present) and set the temperature desired value close to lower limit. At this point verify the fan is all
the time running and that compressor, after a time delay, is started.
Verify as well that the compressor is stopped when temperature set is reached.
If temperature switch should be present, it takes priority on the humidity switch. The humidity switch is
enabled only when temperature set is reached
HIGH PRESSURE SWITCH
The high pressure switch stops the unit when the condensing pressure is higher than the set value. The restart is manual (you need
to press the butt on on the pressure switch) and it can be carried out only when t he pressure is u nder the value indicated by th e
differential set (see table below).
LOW PRESSURE SWITCH
The low pressure switch stops t he unit when the evaporation pressure is lower than the set value. The restart is automatic and it is
only possible when the pressure back over the value indicated by the differential set (see table below).
DEFROST THERMOSTAT
It’s a device which signals to the electronic control, the necessity to make the defrost cycle. Once the defrost cycle is activated, the
defrost thermostat determines also its conclusion
SAFETY DEVICE SETTING
Device Set-point Differential Reset
Antifreeze thermostat °C 1 3 MANUAL
High pressure switch Bar 26 7,7 MANUAL
Low pressure switch Bar 0,7 1 MANUAL
ELECTRICAL DATA
Power supply V/~/Hz 400 / 3+N/ 50 Control circuit V/~/Hz 24 / 1 / 50
Auxiliary circuit V/~/Hz 230 / 1 / 50 Fans power supply V/~/Hz 230 / 1 / 50
Remote condenser fan supply (ITMBTZ versions only) V/~/Hz 230 / 1 / 50

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INSPECTION
When installing or servicing th e unit, it is necessary to strict ly follow the rules reported on this manual, to conform to all the
specifications of the labels on the unit, and to ta ke any possibl e precautions of t he case. Not ob serving the rule s reported on this
manual can cre ate dangerous situations. After r eceiving the unit , immediately check its integrity. The unit left the factory in perfect
condition; any eventual damage must be questioned to the carrier and recorded on the Delivery Note before it is signed. HIDROS
must be informe d, within 8 da ys, of the extent of the damage. The Customer should prepare a written statement of any severe
damage.
LIFTING AND HANDLING
When unloading the unit, it is highly
recommended to avoid any sudden
move in order t o protect ref rigerant
circuit, copper tubes or any ot her
unit component. Units can be lifted
by using a forklift or, in alternative,
using belt s, be ing sure that t he
method of lifting does not damage
the lateral panels and the cover. It
is important to keep the unit
horizontal at all time to a void
damages to the internal
components.
LOCATION AND MINIMUM TECHNICAL CLEARANCES
ITMBT units are designed for internal installation; it is advisab le to create a proper basement, with a size similar to unit fo ot-print.
Unit vibration level is very low: it is advisable however, to fit a rigid rubber band between basement and unit base-frame. If it is the
case, it is po ssible to install ant i-vibration mounts (spring or rub ber), to keep vibrations at a very low level. Absolute care must be
taken to ensure adequate minimum technical cle arances, necessary to guarantee checking and maintenance operation. For these
reasons it is necessary to observe the clearances indicated in the below table.
Mod
A
B C D E
ITMBT330 1000 1000 800 1000 3000
ITMBT400 1000 1000 800 1000 3000
WARNING: The unit should be installed so that maintenance and/or repair services be possible. The
warranty does not cover costs due to lifting apparatus, platforms or other lifting systems required by the
warranty interventions.

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WARNING: All the maintenance operation must be done by TRAINED PEOPLE only.
WARNING: Before every operation of servicing on the unit, be sure that the electric supply is
disconnected.
WARNING: Inside the unit some moving components are present. Be very careful when operating in their
surroundings even if the electric supply is disconnected.
WARNING: The top shell and discharge line of compressor are usually at high temperature level. Be very
careful when operating in their surroundings.
WARNING: Aluminium coil fins are very sharp and can cause serious wounds. Be very careful when
operating in their surroundings.
WARNING: After servicing operation close the unit with cover panels, fixing themwith locking screws
CONDENSATE DRAINING CONNECTIONS
Condensate draining should be done with a rubber pipe passing through the condensate draining connection located on the suction
side of the unit. The discharge hole is lo cated inside the unit and with a 3/4” fem ale thread diameter. On the con densate discharge
pipe it must be installed a syphon with a minimum height equal to the suction pressure of the fan.

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DUCTWORK UNIT CONNECTION
All the ITMBT units are supplied with ductable centrifugal fan.
If it’s necessary to duct only th e discharge side, use a flange with overall dimensions larger than the mouth of the fan, on t he
superior part of the unit (refer to the dimensional drawing of the unit).
If also the suction side has to be ducted, rem ove the filter panel , use a flang e with overall dimensions larger than the suctio n
opening on the front on the unit. Take care to install always a filter on the suction side.
WARNING: It is extremely important to fit a filter on the suction side otherwise the operation mode of the
units can be compromised or damaged.
WARNING: When ductworks are connected it is IMPORTANT to check if the airspeed through the
evaporator is around +/-15%.This parameter allows the unit to operate with the maximum efficiency.
STANDARD UNIT
UNIT WITH FRAME FOR DUCTED INSTALLATION

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REFRIGERANT CONNECTIONS FOR Z VERSIONS
Inspection
The Z version units are supp lied of a remote condenser and t hey need to be connected with th e dehumidifier t hrough refrigerant
lines. The rem ote condenser is equipped of a main swit ch and a fan speed control. Ple ase refer to th e following
paragraphers for the regrigerant connections and to the next chapter for the electrical ones.
Line path/course and max. distance between the sections
For the units in Z version with separate sections, the path/course of the refrigerant pipes is influenced by the location of the sections
themselves and by the structure of the build ing. The pipes have to be in any case as short as p ossible, so that they can
contain/hold the charge lacks and reduce the quantity of refriger ant present in the refrigerant circ uit: Tthe connections must
be iso lated and their length m ust not e xceed 30 m. Our Company is ava ilable for any info rmation even in case of
applications not included in the limits indicated above
Indications for the realisations of the refrigerant connection
According to the relative position of the dehumidifier and of the remote condenser, there are some indications to follow regarding the
realisation of the refrigerant connection.
Condenser installed at a lower level than the dehumidifier:
a) On the rising vertical pipes, oil traps should be fitted every 6 metres to allow oil circulation in the system;
b) Install a collection pit immediately downstream from the bulb of the thermostatic valve;
c) On horizont al suction pipelines a min imum 1% slope should be allowed in order to let the oil easily come back to compressor.
Pipelines diameter can be read in Table II depending on the unit size and the length of refrigerant pipelines
Condenser installed at a higher level than the dehumidifier:
a) Install a liquid trap on suction line at the evaporator outlet whit the same height of the evaporator so that liqu id refrigerant, when
the system is not running, will not fall into compressor;
b) On horizontal suction pipelines a minimum 1% slope should be allowed in order to let the oil easily come back to compressor
Refrigerant diameters lines forversion ITMBTZ
Distance [m] 10 20 30
Mod. gas
[mm] Liquid [mm] gas [mm] Liquid [mm] gas [mm] Liquid [mm]
330 15,8 7,94 15,8 7,94 15,8 7,94
400 15,8 7,94 18 9,52 18 9,52
Liquid line refrigerant charge
Liquid line diameter Refrigerant charge g/m Liquid line diameter Refrigerant charge g/m
7,94 mm 30 9,52 mm 50
Cooling capacity correction factors
Mod. Refr. Line = 0 mt. Refr. Line = 10 mt. Refr. Line =20 mt. Refr. Line =30 mt.
ITMBTZ 1 0,98 0,96 0,95

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REFRIGERANT LAY-OUT VERSION ITM/BT
M
M
EV
FL
EXV
MFC
MFC
SHP
SLP
CND
L
D
YMI
CH CH
SAA
MC
YBP
S
REFRIGERANT LAY-OUT VERSION ITMZ/BT
M
M
M
EV
FL
EXV
MFC
MFC
SHP
SLP
CH CH
CH
CND
CND
MFA
BP
VRL
SV
VRL
YME
YMI
YRR
YRD
SV
L
L
DD
SV
CH CH
CH
IV
SAA
MC YBP
6
6
S
D
CND Condenser FL Liquid line filter
CH Charging plug SV Manual valve
EXT Expansion valve MFC Centrifugal fan
EV Evaporator LR Liquid receiver
SHP High pressure switch VRL One way valve
YRD Solenoid valve YRR Solenoid valve
YMI Solenoid valve BP Pressure transducer
YME Solenoid valve

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ELECTRICAL CONNECTIONS
The power supply must correspond to the electric nominal data (tension, phases, frequency) reported on the label in the front p anel
of the unit. Power connections must be made in accordance to the wiring diagram enclosed with the unit and in accordance to the
norms in force. Power cable and line protection must be sized according to the specification reported on the wiring diagram enclosed
with the unit.
WARNING: The line voltage fluctuations can not be more than ±5% of the nominal value, while the voltage
unbalance between one phase and another can not exceed 2%. If those tolerances should not be
respected, please contact our Company.
WARNING: Electric supply must be in the limits shown: in the opposite case warranty will terminate
immediately. Before every operation on the electric section, be sure that the electric supply is
disconnected.
START UP
Before start-up
Check that all power cables are properly connected and all terminals are hardly fixed.
The voltage at the phase R S T is the one shown in the unit labels.
Check that there is not any refrigerant leakage.
Check that crankcase heaters are powered correctly.
Check that all water connections are properly installed and all indications on unit labels are observed.
Before proceeding to start up check that a ll the cover panels a re re-located in the proper position and locked with fastening
screws.
WARNING: Crankcase heaters must be powered at least 12 hours before start up by closing the main
switch (heaters are automatically supplied when main switch is closed). The crankcase heaters are
working properly if after some minutes the compressor crankcase temperature is about 10÷15°C higher
than ambient temperature.
WARNING: Never switch offthe unit for temporary stop.
WARNING: Never modify internal wiring connections; warranty will be invalidated.

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Before proceeding to start up close the main switch.
All the units are provided with microprocessor control that manages all the various functions of the unit.
The functions described below are applied both for local board control and remote panel control.
To start the unit turn the green switch ON (the inner led will light up).
a) Dehumidification only version: activate humidity switch by rotating the knob o by pressing the instrument keyboard depending
on the type of instrument installed;
a) b) Dehumidification and coolin g Z version unit s: activate humidity and temperature switch by rotating the knob o by pressin g
the instrument keyboard depending on the type of instrument installed;
If the green electrical supply led should not light up (see following page), please reverse two electrical
phases on the connection to the main switch.
CONTROL PANEL
Units are provided with signalling lighting leds that indicate unit operational status.
Below is reported a brief description of their meaning.
-Electrical supply (green): indicates that green switch has been turned in On position and the u nit is
electrically supplied with the following meanings:
led ON: unit running;
led slowly blinking: unit turned off from remote