Thermocold MEX VS 15 RH Service manual

CHILLERS AND INVERTER AIR/WATER HEAT
PUMPS WITH AXIAL FANS
TECHNICAL BULLETIN
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. MUI141247820-05
This manual has been created for informative purpose. The company declines any responsibility for the results of any projecting or any installation based on the
explanations and/or on the technical specifications provided in this manual. It is besides forbidden the reproduction under any form of the texts and of the figures
contained in this manual.
"This manual is a translation from the official italian language version. For reasons of environmental respect the Company will not provide the hard copy in the
original language which could be directly requested or downloaded from the Company website at any time. In case of any dispute, the original language manual
will be the trusted one".

MEX VS Chillers and inverter air / water heat pumps with axial fans
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CE CONFORMITY DECLARATION
DICHIARAZIONE DI CONFORMITÁ CE
THE COMPANY TCM SRL –VIA DEI CICLAMINI 25 70026 MODUGNO BARI –ITALY
LA SOCIETÀ TCM SRL / VIA DEI CICLAMINI 25 70026 MODUGNO BARI - ITALY
DECLARES
DICHIARA
that the unit:
che la macchina:
Definition :
Definizione :
Chiller and inverter air/water heat pumps with axial fans /
Refrigeratori e pompe di calore inverter aria/acqua con
ventilatori assiali
Model N° :
N° modello :
MEX VS 15 RH/16 RH/18 RH/19 RH/112 RH/112T RH/115
RH/115T RH
MEX VS KA 15 RH/16 RH/18 RH/19 RH/112 RH/112T
RH/115 RH/115T RH
Serie N°:
N° di serie:
MEETS THE REQUIREMENTS OF DIRECTIVE 2006/42/CE
È CONFORME AI REQUISITI DELLA DIRETTIVA 2006/42/CE
1. The unit is in CAT. I, so it’s free from the application of Directive 2014/68/UE (Reference to Art. I, paragraph 2, point f)
L’attrezzatura a pressione rientra nella CAT. I. L’unità è quindi esente dall’applicazione della normativa PED 2014/68/UE (Riferimento Art. I, paragrafo 2 punto f).
2. Harmonized standards applied to designing and manufacture : UNI EN 378-1, UNI EN378-2, UNI EN 12735-1
Norme armonizzate applicate alla progettazione ed alla costruzione : UNI EN 378-1, UNI EN378-2, UNI EN 12735-1
3. Others European Directives and harmonized standards applied to the equipment : 2014/35/UE, 2014/30/UE, 2011/65/UE, 2012/19/UE, CEI EN 60335-2-40, CEI
EN 55014-1, CEI EN 55014-2, CEI EN 61000-3-2, CEI EN 61000-3-3, CEI EN 62233
Eventuali altre Direttive Europee e norme armonizzate applicate all’attrezzatura : 2014/35/UE, 2014/30/UE, 2011/65/UE, 2012/19/UE, CEI EN 60335-2-40, CEI EN
55014-1, CEI EN 55014-2, CEI EN 61000-3-2, CEI EN 61000-3-3, CEI EN 62233
The manufacturer states, also, that the technical file is compiled and kept at TCM Srl.
Il fabbricante inoltre dichiara che il fascicolo tecnico della macchina è costituito e custodito presso TCM Srl.

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INDEX
1PURPOSE AND CONTENT OF THE MANUAL ............................................................................................................................ 5
1.1 CONSERVATION OF THE MANUAL .......................................................................................................................................... 5
1.2 GRAPHIC SYMBOLS................................................................................................................................................................. 5
2SAFETY LAWS ......................................................................................................................................................................... 5
3PERMITTED USES ................................................................................................................................................................... 6
4GENERAL SAFETY GUIDELINES................................................................................................................................................ 6
4.1 WORKERS’ HEALTH AND SAFETY ............................................................................................................................................ 6
4.2 PERSONAL SAFETY EQUIPMENT ............................................................................................................................................. 7
4.3 SAFETY SYMBOLS.................................................................................................................................................................... 7
4.4 REFRIGERANT SAFETY DATA SHEET ........................................................................................................................................ 8
5TECHNICAL CHARACTERISTICS................................................................................................................................................ 8
5.1 FRAME.................................................................................................................................................................................... 9
5.2 REFRIGERANT CIRCUIT ........................................................................................................................................................... 9
5.3 COMPRESSORS ....................................................................................................................................................................... 9
5.4 AIR SIDE EXCHANGERS............................................................................................................................................................ 9
5.5 FANS ....................................................................................................................................................................................... 9
5.6 USER SIDE HEAT EXCHANGERS ............................................................................................................................................... 9
5.7 ELECTRIC BOX ......................................................................................................................................................................... 9
5.8 CONTROL SYSTEM .................................................................................................................................................................. 9
5.9 MONITORING AND PROTECTION DEVICES ........................................................................................................................... 10
5.10 HYDRAULIC CIRCUIT ............................................................................................................................................................. 10
5.11 FAN SPEED CONTROL............................................................................................................................................................ 10
6AVAILABLE VERSIONS .......................................................................................................................................................... 10
6.1 OPTIONAL ACCESSORIES ...................................................................................................................................................... 11
7INSTALLATION...................................................................................................................................................................... 12
7.1 GENERALITY.......................................................................................................................................................................... 12
7.2 LIFTING AND HANDLING....................................................................................................................................................... 12
7.3 LOCATION AND MINIMUM TECHNICAL CLEARANCES .......................................................................................................... 12
CAUTION: IT IS OBLIGATORY TO INSTALL THE UNIT ON A FIRM AND APPROPRIATE BASEMENT TO SUPPORT ITS WEIGHT.CONSIDERING THE WEIGHT OF THE
UNIT,POSSIBLE VIBRATIONS AND RESULTANT NOISE,WE DO NOT RECOMMEND SUSPENSION INSTALLION OF THE UNIT;IN THIS CASE,THE FIRM IS NOT
RESPONSIBLE FOR ANY DAMAGE OR INCONVENIENCE THAT MAY RESULT............................................................................................................ 13
7.4 HYDRAULIC CONNECTIONS .................................................................................................................................................. 13
7.4.1 Drainage connection .................................................................................................................................................... 13
7.4.2 Plant circuit charging.................................................................................................................................................... 13
7.4.3 Plant drainage system .................................................................................................................................................. 14
7.4.4 Hydraulic circuit............................................................................................................................................................ 14
7.5 REFRIGERANT DIAGRAM OF 06-08 ....................................................................................................................................... 15
7.6 REFRIGERANT DIAGRAM OF 10-12 ....................................................................................................................................... 15
7.7 REFRIGERANT DIAGRAM OF 14-16 ....................................................................................................................................... 15
7.8 ELECTRICAL CONNECTIONS .................................................................................................................................................. 15
7.8.1 Wiring terminal block ................................................................................................................................................... 16
7.8.2 Terminal block and the electric box.............................................................................................................................. 17
8START UP ............................................................................................................................................................................. 17
9SHUTDOWNS FOR LONG PERIODS........................................................................................................................................ 18
10 MAINTENANCE AND PERIODICAL CONTROLS ................................................................................................................... 18
10.1 ENVIRONMENTAL PROTECTION ........................................................................................................................................... 19
11 APPLIANCE RECYCLING ..................................................................................................................................................... 19
12 TECHNICAL DATA.............................................................................................................................................................. 20
13 ELECTRIC DATA OF THE UNIT AND AUXILIARIES ............................................................................................................... 22
14 HYDRAULIC CIRCUIT AVAILABLE HEAD PRESSURE ............................................................................................................ 22

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15 OPERATION LIMITS .......................................................................................................................................................... 24
15.1 EVAPORATOR WATER FLOW RATE ....................................................................................................................................... 24
15.2 COLD WATER TEMPERATURE (SUMMER OPERATION)......................................................................................................... 24
15.3 HOT WATER TEMPERATURE (WINTER OPERATION)............................................................................................................. 24
15.4 AMBIENT AIR TEMPERATURE AND SUMMARIZING TABLES ................................................................................................. 24
16 CORRECTION FACTORS FOR USE OF GLYCOL .................................................................................................................... 26
17 DIMENSIONS .................................................................................................................................................................... 26
17.1 MODELS MEX VS 15 RH/16 RH.............................................................................................................................................. 26
17.2 MODELS MEX VS 18 RH/19 RHIN/OUT: 1”M......................................................................................................................... 26
17.3 MODELS MEX VS 112 RH /112T RH /115 RH /115T RH ........................................................................................................ 27
17.4 INTERNAL PARTS OF THE UNIT ............................................................................................................................................. 27
17.4.1 Mod. MEX VS 15 RH / 16 RH......................................................................................................................................... 27
17.4.2 Mod. MEX VS 18 RH / 19 RH......................................................................................................................................... 28
17.4.3 Mod. MEX VS 112 RH / 112T RH / 115 RH / 115T RH ................................................................................................... 28
18 WIRING DIAGRAMS.......................................................................................................................................................... 29
18.1 MODELS MEX VS 15 RH /16 RH /18 RH /19 RH.................................................................................................................... 29
18.2 MODELS MEX VS 112 RH /115 RH ........................................................................................................................................ 32
18.3 MODEL MEX VS 112T RH /115T RH ...................................................................................................................................... 35
19 HYDRAULIC DIAGRAM TYPE ............................................................................................................................................. 38
20 CONTROL LOGICS ............................................................................................................................................................. 38
21 HANDBOOK FOR SOME CONFIGURATIONS OF INSTALLATIONS........................................................................................ 38

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The manual of MEX VS units collects all the necessary information for the better use of the equipment under safety conditions for
the operator thus meeting the requirements listed in the 2006/42/CE Equipment Directive and following amendments.
1PURPOSE AND CONTENT OF THE MANUAL
This manual provides basic information as for the installation, the operation and the maintenance of the 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.
WARNING: Although this manual is also destined for the end-user utilizations, some discibed activities are allowed
only for trained technical personnels who should be in possession of Vocational and Technical Training allowing
them to be responsible for carrying out the activity. They should be properly updated with courses approved by the
competent authorities. These activities includ: installation, both ordinary and extraordinary maintenance,
appliance disposal and any other activity required by "qualified staff."
After the end of installation and/or maintenance of the appliance, the qualified operator has a duty to properly
inform the end-user about the use of the appliance and the necessary periodical checks.
The installer is responsible to deliver all necessary documentation (including this manual) to the user and should
ensure him to keep it in a safe place near the appliance where it can be available at any time.
This 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, therefore, is not constrained to update the manuals for previous versions of machines.
It’s recommended that, the user must follow the instructions contained in this booklet, especially those concerning the safety and
routine maintenance.
1.1 CONSERVATION OF THE MANUAL
The manual has to be always kept by the user for future reference. It has to be stored in a safe place, away from dusts and
moisture. It has to be available and accessible to all users who shall consult it when 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.
1.2 GRAPHIC SYMBOLS
Indicates operations that can be dangerous for people and/or disrupts the correct operation of the equipment.
Indicates prohibited operations.
Indicates important information that the operator has to follow in order to guarantee the correct operation of the
equipment in complete safety.
2SAFETY LAWS
The MEX VS units have been designed in compliance with the following Directives and Harmonised Norms concerning the safety of
the appliances:
97/23/CE, 2014/35/UE, 2014/30/UE, 2011/65/UE, 2012/19/UE Community Directives
UNI EN 378-1, 378-2, UNI EN 12735-1 Norms
CEI EN 60335-2-40 Norms
CEI EN 55014-1, CEI EN 55014-2, CEI EN 61000-3-2, CEI EN 61000-3-3, CEI EN 62233 Norms
And the following directives and regulations concerning the energy labeling and the eco-friendly products:
Community directive 2009/125/CE and subsequent transpositions
Community directive 2010/30/UE and subsequent transpositions
Regulation UE No 811/2013
Regulation UE No 813/2013

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3PERMITTED 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.
4GENERAL SAFETY GUIDELINES
Before beginning to operate on MEX VS 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 this manual.
It’s strictly forbidden to remove and/or tamper with any safety device.
Children or unassisted disabled persons are not allowed to use the appliance.
Do not touch the appliance when barefoot or parts of the body are wet or damp.
Do not clean the unit when the power is ‘ON’.
Do not pull, remove or twist the electrical cables coming out from the unit, even if it is disconnected from the main
power supply.
Do not step with your feet on the appliance, sit down and/or place any type of object.
Do not spray or pour water directly on the unit.
Do not dispose of, abandon or leave within reach of children packaging materials (cardboard, staples, plastic bags,
etc.) as they may represent a hazard.
Any routine or not-routine maintenance operation shall be carried out when the equipment has been shut down,
disconnected from electric power sources.
Do not put neither your hands nor insert screwdrivers, spanners or other tools into moving parts of the equipment.
The equipment supervisor and the maintenance man have to receive suitable training for the performance of their
tasks in safety.
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.
4.1 WORKERS’ HEALTH AND SAFETY
The European Community has adopted a number of directives on workplace’s health and safety, which are 89/391/CEE,
89/686/CEE, 2009/104/CE, 86/188/CEE and 77/576/CEE directives, and the subsequent integrations/modification. Every employer
shall implement such provisions and ensure that their workers to respect them. We observe therefore that:
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/or damage the equipment
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 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.
The unit operates with R410A refrigerant gas, which is a greenhouse gas according to the F-gas Regulation (EU) 517/2014
(mandatory in the European area). This Regulation, among the provisions, requires all operators intervening in greenhouse gas
systems to be in possession of a certificate issued or recognized by the competent authority, attesting to a successful completion
of an examination entitling them to carry out such work. In particular:
Device contains up to 3kg of the total amount of refrigerant gas: Category II certificate.
Device contains 3kg or more than 3kg of the total amount of refrigerant gas: Category I certificate.
The refrigerant R410A in gaseous form is heavier than air and tends to concentrate highly in little ventilated environments when a
leak occurs. Its inhalation can cause dizziness, suffocation and can develop lethal gas if it becomes in contact with open flames or
hot objects, (please see “REFRIGERANT SAFETY DATA SHEET” paragraph 4.4).

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For any intervention on the heat pump:
Wear appropriate Personal Protective Equipment (PPE) specifically, gloves and goggles.
Ensure that the workplace is well ventilated. Do not work in closed rooms or ditches with weak air circulation.
Do not work on the refrigerant near open flames or near hot parts.
Avoid any refrigerant leakage into the environment and pay particular attention to leakage from pipes and/or
fittings after evacuating the refrigerant circuit.
4.2 PERSONAL SAFETY EQUIPMENT
When operating and maintaining the MEX VS units, it is required to 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.
4.3 SAFETY SYMBOLS
The unit features the following safety signs, which has to be complied with:
General hazards
Electric shock hazard
Presence of moving organs
Presence of surfaces that may cause injures
Presence of hot surfaces that can cause burns

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4.4 REFRIGERANT SAFETY DATA SHEET
Name:
R410A (50% Difluoromethane (R32); 50% Pentafluoroethane (R125).
RISKS INDICATIONS
Major risks:
Asphyxia
Specific risks:
The rapid evaporation may cause freezing.
FIRST AID
General information:
Never give anything by mouth to an unconscious person.
Inhalation:
Move to fresh air.
Oxygen or artificial respiration if necessary.
Do not administer adrenaline or similar drugs.
Eyes contact:
Rinse carefully with water for at least 15 minutes and consult a doctor.
Contact with skin:
Wash immediately with plenty of water.
Take off immediately the contaminated clothing.
FIRE PREVENTION
Extinguishing Media:
Whatever.
Specific risks:
Increase in pressure.
Specific methods:
Use water spray to cool containers
ACCIDENTAL RELEASE ACTIONS
Personal precautions:
Evacuate personnel to safe areas.
Provide adequate ventilation.
Use personal protective equipment.
Environmental precautions:
Evaporate.
Cleaning method:
Evaporate.
HANDLING AND STORAGE
Manipulation
Action/technical precautions:
Provide sufficient air exchange and/or suction in work places.
Recommendations for safe use:
Do not breathe vapors or aerosol.
Storage:
Close tightly and store in a cool, dry and well ventilated place.
Store in original container. Incompatible products: explosive, flammable materials, Organic peroxide
EXPOSURE CONTROL / PERSONAL PROTECTION
Control parameters:
AEL (8-h e 12-h TWA) = 1000ml/m³ for each of the two components.
Respiratory protection:
For rescue and maintenance operation in storage tanks use self-contained respirator apparatus.
The vapors are heavier than air and can cause suffocation by reducing oxygen available for breathing.
Eyes protection:
Safety glasses.
Protection of hands:
Rubber gloves.
Hygiene measures:
Do not smoke.
PHYSICAL AND CHEMICAL PROPERTIES
Colour:
Colourless.
Odor:
Light.
Boiling point:
-52.8°C at atmospheric pressure.
Lighting point:
It does not ignite.
Density:
1.08kg/l at 25°C.
Solubility in water:
Negligible.
STABILITY AND REACTIVITY
Stability:
No reactivity when used with the appropriate instructions.
Materials to avoid:
Highly oxidizing materials. Incompatible with magnesium, zinc, sodium, potassium and aluminum.
The incompatibility is more serious if the metal is present in powdered form or if the surfaces were, recently,
unprotected.
Decomposition products
These products are halogenated compounds, hydrogen fluoride, carbon oxides (CO, CO2), carbonyl halides.
Risks:
TOXICOLOGICAL INFORMATION
Acute toxicity:
(R32) LC50/ inhalation /4 hours/on rat >760 ml/l
(R125) LC50/ inhalation /4 hours/on rat >3480 mg/l
Local effects:
Concentrations substantially above the TLV may cause narcotic effects.
Inhalation of decomposed products of high concentrations may cause respiratory failure (pulmonary edema).
Long term toxicity:
Did not show carcinogenic, teratogenic or mutagenic effects in animal experiments.
ECOLOGICAL INFORMATION
Global Warming Potential
2088
GWP (R744=1)
Ozone Depletion Potential
0
ODP (R11=1):
Disposal considerations:
usable with reconditioning.
5TECHNICAL CHARACTERISTICS

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The MEX VS water chillers and heat pumps series are designed for applications in residential and commercial areas, These units
are extremely versatile and can operate in heat pump mode with the ability of producing hot water at a temperature of 58°C for
environmental heating and sanitary applications. The INVERTER compressor with brushless DC motor technology, matched with
electronic expansion valve, pump and variable speed blower are generally used for optimizing the power consumption and
efficient operation of the refrigerating components.
5.1 FRAME
All the unist of MEX VS series are made up of hot-galvanised thick sheet metal, painted with polyurethane powder enamels at
180°C to ensure the best resistance against atmospheric agents. The frame is self-supporting with removable panels. All screws
and rivets for outdoor installations are in galvanized steel.
5.2 REFRIGERANT CIRCUIT
The refrigerant gas used in these units is R410A. The refrigerant circuit has been manufactured by means of international primary
brands components and according to the UNI EN 13134 Rule concerning welding procedures. The refrigerant circuit includes: 4
way reverse cycle valve, electronic expansion valve, liquid separator, liquid receiver, valves for maintenance and control, pressure
safety device, pressure transducers to accurately adjust the evaporating and condensing pressures, filters for throttling valve to
avoid its clogging.
5.3 COMPRESSORS
The installed DC inverter compressors are rotary hermetic twin rotary type designed to be used with R410 refrigerant.
The compressors are mounted in a separate chamber, isolated from the air stream in order to reduce the noise, and are equipped
with crankcase heater, In order to avoid the oil dilution which may cause seizure of the compressor. The crankcase heater
operates when the compressor remains off for at least 30 minutes and if the discharge temperature is below 20°C (with hysteresis
of 2.0°C). When the compressor restarts, the crankcase heater will stop operation. The crankcase heater works even if the unit is
in shut off mode, which will protect the compressor from restartup failure.
We recommend you to turn ON the unit and to put it in standby mode at least for 6 hours before starting the operation, especially
if the system has been completely turned off for a period of time.
The checking of the compressors is possible through removing the frontal and lateral panels of the unit allowing easy maintenance
of the compressors even when the unit is operation.
5.4 AIR SIDE EXCHANGERS
The air side exchangers are made up of copper pipes and aluminium fins. The tubes are mechanically expanded into the
aluminium fins to improve the heat exchange factor. The geometry of these condensers guarantee a low air side pressure drop
and, then, the use of low rotation (and low noise emission) fans.
5.5 FANS
The fans are axial type with aluminium aerofoil blades. They are statically and dynamically balanced and supplied complete of the
safety fan guard according to the CEI EN 60335-2-80 Rule (safety for electrical apparatus of domestic and similar use). They are
mounted on the unit frame by interposition of rubber vibration dampers. The electric motors are all brushless DC type with 8
poles (about 200/1000 rpm). The motors are directly driven with an integrated thermal overload protection. The protection class
of the motors is IP X44.
5.6 USER SIDE HEAT EXCHANGERS
The user side heat exchangers are made up of AISI 304 stainless steel braze-welded plates type. The user heat exchangers are
factory insulated with flexible close cell material and can be equipped with antifreeze heater (KA optional). Each heat exchanger is
provided with a temperature sensor working as antifreeze protection that activates the circulator, even in the case when the unit
is turned off when the conditions set in the controller have been occurred.
5.7 ELECTRIC BOX
The electric box is manufactured according to the current European Union laws. The accessibility to the board is possible after
removing the cover panel of the unit using proper tools. The protection degree is IP24. The terminal board is supplied with voltage
free contacts for remote ON-OFF, winter/summer change over, auxiliary heater, sanitary water temperature sensor control of
external 3-way valve and free contacts for remote control panel and for the management of the dual set point of operation.
5.8 CONTROL SYSTEM
All the units of MEX VS series are standard supplied with a microprocessor adopting an overheating control logic program through
the electronic expansion valve which is driven by the pressure transducers signals. The microprocessor is also capable of
controlling the following functions: water temperature regulation, antifreeze protection, compressors’ time setting, compressor
automatic starting sequence, alarm reset, alarm management and operating LED. Upon request, the microprocessor can be
connected to a BMS remote control system and to the simpler HNS system with our terminal units. The control system together
with the INVERTER technology and the on board sensors continuously monitor and adapt the performance of the inverter
compressor, of the pump and of the fan (2 fans for the models: 112 RH, 112T RH, 115 RH and 115T RH) according to the value of
cooling power at any working conditions requested by the user.

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5.9 MONITORING AND PROTECTION DEVICES
All units are standard supplied with the following monitoring and protection devices: return water temperature sensor installed at
the return water pipe line from the plant, operating and antifreeze sensor installed at the outlet pipe of the water to the plant,
high pressure transducer, low pressure transducer, compressor’s inlet and outlet temperature sensors, compressors thermal
protection device, fans thermal protection device, water side installed water flow switch to protect the evaporator, high pressure
HP flow switch.
5.10 HYDRAULIC CIRCUIT
The MEX VS chillers units are supplied with an integrated hydraulic circuit including: circulating pump with high efficiency DC
brushless motor (EEI≤0,23 for the sizes 112 RH and 115 RH, however for 15 RH, 16 RH, 18 RH and 19 RH EEI≤0,20), suitable for
chilled water utilization and directly run by a controller on board, plate heat exchanger, expansion vessel (The expansion vessel
capacity depends on the size of the unit, refer to the technical data shown in chapter 12), safety valve (6 bar) that have to be
connected with a colleting tank, the manual air release valve and the flow switch.
5.11 FAN SPEED CONTROL
This type of control is managed by the microprocessor and is necessary for optimizing the pressure of evaporation/condensation
during summer/winter operation in order to allow proper running of the unit.
6AVAILABLE VERSIONS
MEX VS reversible heat pump with integrated hydronic system (expansion vessel, safety valve, pressure gauge, modulating pump,
flow switch, manual air release valve, load/unload valve).
The available models are: 15RH, 16 RH, 18 RH, 19 RH, 112 RH, 112T RH, 115 RH, and 115T RH. The sizes of 112 RH and 115 RH are
available in both single-phase and three-phase electric power. However the other sizes are all single-phase electric power units.
Accessory denomination:
Field
Variant
Description
Name
KA
1
The antifreeze kit uses a self-regulating heating cable wrapped around the
basement of the outdoor unit near the condensing coil and two in PET heaters
placed on the faces of the plate heat exchanger.
KA
WARNING: The antifreeze kit is an optional factory-installed accessory and cannot be mounted after purchasing
the unit.

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6.1 OPTIONAL ACCESSORIES
OPTIONAL ACCESSORIES NOT INSTALLED IN THE FACTORY
AG
Anti-vibration rubber pad to be installed in the chassis of the unit for possible shock absorption.
KDS
Kit for dual set point (already included in Hi-T) that allows the control of a second set point of operation for the plant
side.
IMPORTANT NOTE
ONLY THE OPTIONAL ACCESSORIES THAT ARE NOT INSTALLED IN THE FACTORY CAN BE REQUIRED AFTER THE ORDER OF THE
UNIT, WHILE THE FACTORY INSTALLED ACCESSORIES CAN NOT BE REQUIRED AFTER THE ORDER OF THE UNIT.
WARNING: The optional accessories are subject to revisions. They may be changed without the need to update the previous
manuals and without giving prior notice. If you are interested in buying these accessories after you have purchased the unit,
please contact our offices for the availability.

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7INSTALLATION
WARNING: All the operation described in next chapters MUST BE DONE BY TRAINED PEOPLE ONLY. Before any
operation on the unit, be sure that the electric supply is disconnected. Be sure also, using suitable obstructions,
that can avoid accidental power supply switching ON until the end of all operations.
7.1 GENERALITY
When installing or servicing the unit, it is necessary to strictly follow the rules listed in this manual, to conform to all the
specifications of the labels on the unit, and to take any possible precautions. Not observing the rules reported on this manual can
create dangerous situations.
After receiving the unit, immediately check its integrity. The unit left the factory in perfect condition; any eventual
damage has to be questioned to the carrier and recorded on the Delivery Note before signing it.
The company has to be informed, within 8 days, of the extent of the damage. The Customer should prepare a written statement of
any severe damage.
WARNING: The units are designed for outdoor installation. The place of installation must be entirely far away from
fire risk. All the necessary measures should be adopted in order to prevent the fire risk in the place of installation. The
outdoor ambient temperature shall not exceed 46°C. Above this value, the unit is no longer covered by the directives
in force in the area of pressure equipment.
WARNING: The unit should be installed so that adequate clearance is available for maintenance and repairation. The
warranty does not cover costs related to platforms or handling equipment necessary for any maintenance.
All maintenance and testing operations should be carried out only by QUALIFIED PERSONNEL.
Before any operation on the unit, make sure the power supply is disconnected.
WARNING: MOVING PARTS, RISK OF DEATH.
Disconnect the power supply and ensure that the fan is stopped before opening the front panel.
The temperatures of heads and discharge piping of the compressor are usually high.
Be careful when working near condensing coils.
The aluminum fins are very sharp and can cause serious injuries.
After the maintenance operations, close the panels tightly with the fastening screws.
7.2 LIFTING AND HANDLING
When unloading and installing the unit, it is highly recommended to
avoid any sudden move in order to protect the inner components.
Units can be lifted by means of a forklift or, in alternative, of belts,
being sure not to damage the lateral panels and the cover. It is
important to keep the unit horizontal during these operations.
7.3 LOCATION AND MINIMUM TECHNICAL CLEARANCES
The all MEX VS units are designed for outdoor installation: any cover over the unit and location near trees (even if they partially
cover the unit) has to be avoided in order to prevent air recirculation. It is advisable to create a proper basement, with a size
similar to unit foot-print. Unit vibration level is very low: it is advisable however, to fit a rigid rubber band between basement and
unit base-frame. It is also possible to install anti-vibration supports (springs or rubbers) to keep vibrations at a very low level.
Absolute care has to be taken to ensure adequate air volume to the condenser. Re-circulation of discharge air has to be avoided;
failure to observe this point will result in poor performance or activation of safety controls. For these reasons it is absolutely
necessary to respect the following clearances:
MOD.
A
B
C
D
E
MEX VS 15 RH
1500
500
400
400
500
MEX VS 16 RH
1500
500
400
400
500
MEX VS 18 RH
1500
500
400
400
500
MEX VS 19 RH
1500
500
400
400
500
MEX VS 112RH/112T RH
1500
500
400
400
500
MEX VS 115RH/115T RH
1500
500
400
400
500

MEX VS Chillers and inverter air / water heat pumps with axial fans
13
CAUTION: It is obligatory to install the unit on a firm and appropriate basement to support its weight.
Considering the weight of the unit, possible vibrations and resultant noise, we do not recommend suspension
installion of the unit; in this case, the firm is not responsible for any damage or inconvenience that may result.
7.4 HYDRAULIC CONNECTIONS
The hydraulic connections have to be installed in accordance with national and local regulations; pipes can be made up of steel,
galvanized steel or PVC. Pipes have to be designed depending on the nominal water flow and on the hydraulic pressure drops of
the system. All pipes have to be insulated with closed-cell material of adequate thickness. Chillers have to be connected to piping
by means of flexible joints. Piping should include:
•Hole thermometers to monitor the system’s temperature.
•Manual gate valves to separate the chiller from the hydraulic circuit.
•Y-shaped metallic filter and a dirt separator (to be mounted on the inlet pipe) with a mesh not larger than 1mm.
•Charging group and discharge valve, where necessary.
WARNING: Make sure that, when designing the pipe length and diameter, do not exceed the maximum head loss
on the plant side, please see the technical data given in the table of Paragraph 12 (available pressure head).
WARNING: Connect the pipes to the attacks by using always key against key system.
WARNING: The expansion vessel have a limited volume. The installator have to provide a further expansion vessel
if it is necessary.
WARNING: Unit water inlet pipe have to be in correspondence with the connection labelled: ”WATER INLET”,
otherwise the evaporator may freeze.
WARNING: It is compulsory to install on the WATER INLET connection a metallic filter (with a mesh not larger than
1mm) and a dirt separator. the warranty will no longer be valid If the water flow switch was manipulated or
altered or if the metallic filter and/or dirt separator were not installed. The filter and the dirt separator have to be
kept clean, therefore make sure that are clean after the unit installing the unit, and then check them periodically.
All units are standard supplied with the water flow switch (factory installed). The warranty will be invalidated if the
water flow switch was altered, removed, or if the water filter and the dirt separator were not installed on the unit.
Please refer to the wiring diagram for the water flow switch electric connections.
Make sur that the heating system and the safety valves must comply with the requirements of EN 12828.
7.4.1 Drainage connection
All the units of MEX VS series have been designed to use their own base as a drain pan; a plastic pipe fitting is standard provided
to be installed onto the lower part of the unit in the special housing enabling the connection of a drainage pipe.
Each unit is also provided, on the basement of the hydronic kit (at the heat exchanger side), with a hole that can allow to drain any
condensed water can leach from plumbing pipes. As the pipes must be well-insulated, the production of condensed water is
however very low and therefore the connection of a drainage pipe to that hole is not very required.
7.4.2 Plant circuit charging
WARNING: Verify all the charging/topping up operations.
WARNING: Before beginning the charging/topping up operation of the plant circuit, disconnect the unit for the
electric power supply.
WARNING: The charging/topping up of the plant circuit must always be done under controlled conditions of
pressure (max 1 bar). Make sure that you have installed on the line of charging/topping up a pressure
reducerdevice and a relief valve.
WARNING: The water on the charging/topping up pipe must be suitably pre-filtered from any impurities and
suspended particles. Make sure that you have installed a cartridge filter removable. Make sure that an extractable
cartridge filter and a dirt separator have been installed.
WARNING: It is required to proceed by air purging periodically in order to eliminate the accumulated air from the
plant circuit system.
WARNING: Make sure to install an automatic air vent valve at the highest point of the system.
Drainage pipe fitting
Drainage pipe fitting housing
Drainage pipe fitting connected to the unit

MEX VS Chillers and inverter air / water heat pumps with axial fans
14
7.4.3 Plant drainage system
When it is necessary to drain the plant, close at first the inlet and outlet manual gate valves (not supplied) and then remove the
pipes that are disposed externally on the water inlet and on the water outlet in order to spill away the liquid contained in the unit
(for easier operation, it is recommended to install externally two draining valves, on the water inlet and on the water outlet,
between the unit and the manual gate valves).
7.4.4 Hydraulic circuit
Models: MEX VS 15 RH and 16 RH
Models: MEX VS 18 RH and 19 RH
A
B
HF
G
ED
C
i-HWAK 06/08 V4
A
B
HF
G
ED
C
i-HWAK 10/12 V4
SERIE MEX VS 112 RH and 115 RH
A
B
H
F
G
E
D
C
i-HWAK 14/16 V4
KEY
A
Plate heat exchanger
E
Expansion vessel
B
Flow switch
F
Manual air vent valve
C
Service valve
G
Safety valve
D
High efficiency circulating pump with
H
Pressure gauge
You can use the service valve, when it is necessary to refill the plant or adapt the
concentration of glycol. Unscrew the cap of the service valve and connect to the
hose a pipe of 14 mm or (inner diameter size - check the faucet model that is
installed on your own unit) connected to the water network, and then load the
system by unscrewing the knurled nut. When the operation is concluded, retighten
the knurled nut and screw on the cap. In any case, we recommend you to use for
the water loading of the plant an external tap whose arrangement is by the
installer.
Cap with gasket
Knurled nut

MEX VS Chillers and inverter air / water heat pumps with axial fans
15
7.5 REFRIGERANT DIAGRAM OF 15RH-16 RH
IN OUT
DT
ST
LP HP
4WV
LR EEV
FL FL
C
CLS
Pr
PV
PV
MF
SE
M
P
C
COMPRESSOR
CLS
COMPRESSOR LIQUID SEPARATOR
ST
COMPRESSOR INLET TEMPERATURE
DT
COMPRESSOR OUTLET TEMPERATURE
HP
HIGH PRESSURE TRANSDUCER
Pr
HIGH PRESSURE FLOW SWITCH
LP
LOW PRESSURE TRANSDUCER
LS
LIQUID SEPARATOR (only for model 09)
4WV
INVERTING CYCLE VALVE
LR
LIQUID RECEIVER
EEV
ELECTRONIC EXPANSION VALVE
FL
FILTER
M
AXIAL FAN
MF
MUFFLER SILENCER
SE
OUTDOOR AIR TEMPERATURE
P
CIRCULATOR ON BOARD UNIT
IN
WATER INLET TEMPERATURE
OUT
WATER OUTLET TEMPERATURE
7.6 REFRIGERANT DIAGRAM OF 18 RH-19 RH
IN OUT
DT
OS
i-HWAK 10 / 12 V4
ST
LP HP
4WV
LR EEV
FL FL
FL
C
CLS
PrPr
PV
PV
CP
CP SE
M
P
C
COMPRESSOR
CLS
COMPRESSOR LIQUID SEPARATOR
OS
OIL SEPARATOR
ST
COMPRESSOR INLET TEMPERATURE
DT
COMPRESSOR OUTLET TEMPERATURE
HP
HIGH PRESSURE TRANSDUCER
Pr
HIGH PRESSURE FLOW SWITCH
LP
LOW PRESSURE TRANSDUCER
4WV
INVERTING CYCLE VALVE
LR
LIQUID RECEIVER
EEV
ELECTRONIC EXPANSION VALVE
FL
FILTER
M
AXIAL FAN
SE
OUTDOOR AIR TEMPERATURE
P
CIRCULATOR ON BOARD UNIT
IN
WATER INLET TEMPERATURE
OUT
WATER OUTLET TEMPERATURE
CP
CAPILLARY
7.7 REFRIGERANT DIAGRAM OF 112RH-115 RH
IN OUT
DT
OS
ST
LP HP
4WV
LR EEV
FL FL
FL
C
CLS
Pr
PV Pr
PV
CP
SE
MM
P
C
COMPRESSOR
CLS
COMPRESSOR LIQUID SEPARATOR
OS
OIL SEPARATOR
ST
COMPRESSOR INLET TEMPERATURE
DT
COMPRESSOR OUTLET TEMPERATURE
HP
HIGH PRESSURE TRANSDUCER
Pr
HIGH PRESSURE FLOW SWITCH
LP
LOW PRESSURE TRANSDUCER
4WV
INVERTING CYCLE VALVE
LR
LIQUID RECEIVER
EEV
ELECTRONIC EXPANSION VALVE
FL
FILTER
M
AXIAL FAN
SE
OUTDOOR AIR TEMPERATURE
P
CIRCULATOR ON BOARD UNIT
IN
WATER INLET TEMPERATURE
OUT
WATER OUTLET TEMPERATURE
CP
CAPILLARY
7.8 ELECTRICAL CONNECTIONS
Check out that the power supply meets the unit’s electric nominal data (tension, phases, frequency) reported on the label in the
unit’s side panel. Power connections have to be made in accordance to the wiring diagram enclosed with the unit and in
conformity with the national and international norms in force (providing equipment as general magnetothermic circuit breaker,
differential circuit breakers for each electric line, proper grounding for the plant, etc.). Power cables, electric protections and line
fuses have to be sized according to the specifications listed in the wiring diagram enclosed with the unit and in the electrical data
contained in the table of technical characteristics (see Paragraph 12).

MEX VS Chillers and inverter air / water heat pumps with axial fans
16
WARNING: The electrical panel is located under the coping plate. It is necessary to respect the minimum clearances
given in section 7.3 in order to be able to connect the wires.
WARNING: Installer has to provide a general circuit breaker (for example a magnetothermic circuit breaker) at the
beginning of unit circuit system.
WARNING: The supply voltage’s fluctuations cannot exceed ±10% of the nominal value. Should this tolerance not be
respected, please contact our technical department.
WARNING: The power supply have to respect the listed limits: failing this, warranty will terminate immediately.
Before any operation on the unit, be sure that the power supply is disconnected.
WARNING: The water flow switch (B component in the previous hydraulic circuit and factory installed) have ALWAYS
to be connected following the indications listed in the wiring diagram. Never bridge the water flow switch
connections in the terminal board. Should the water flow switch connections altered or not properly made, the
guarantee will be invalidated.
WARNING: The remote control panel is connected to the water chiller by means of no.4 wires having a 1,5 mm2
section. The power supply cables have to be separated from the remote control wires. The maximum distance is 50m.
WARNING: The remote control panel cannot be installed in areas with strong vibrations, corrosive gases, and excess
of dirtiness or high humidity levels. Leave free the area near the cooling openings.
7.8.1 Wiring terminal block
Electrical wiring have to be done only by qualified personnel.
The electrical connections have to be realized by qualified personnel. The terminal block is located under the cover of the unit
close to the side where the controller is positioned. To get access to the terminal block, please see the indications reported in the
paragraph 7.8.2. The wiring to the terminal block has to be realized in accordance to the below notes (the drawing is for
illustration).
The illustrations below are for the corresponding sizes 112T RH and 115T RH, as for the other models, the only difference is
concerning the power supply input terminals.
The connections indicated below are standard. Other connections are shown in the manual MCO of the on board control of MEX VS
unit (see "TABLE OF CONFIGURATIONS ALLOWED TO USER AND INSTALLER"), depending on the configurations adopted.
Terminal
Connection
Type
PE
Connect to the grounding wire of the power supply
Power supply input 1-Ph/N/PE,230V, 50Hz
(only for the sizes
15RH/16RH/18RH/19RH/112RH/115RH)
N
Connect to the neutral wire of the power supply
L
Connect to the phase wire of the power supply
PE
Connect to the grounding wire of the power supply
Power supply input for 3-Ph/N/PE, 400 Vac,
50Hz.
(only for the sizes 112T RH and 115T RH)
N
Connect to the neutral wire of the power supply
L1
Connect this therminal to L1 of the three-power supply
L2
Connect this therminal to L2 of the three-power supply
L3
Connect this therminal to L3 of the three-power supply
NC1
Normally closed terminal (230Vac).
Changeover contact, 1- phase power supply
230Vac, 50Hz, 5A resistives, 1A inductives
N
Terminal for neutral wire (230Vac).
NO1
Normally open terminal (230Vac).
NC2
Normally closed terminal (230Vac).
Changeover contact, 1- phase power supply
230Vac, 50Hz, 5A resistives, 1A inductives
N2
Terminal for neutral wire (230Vac)
NO2
Normally open terminal (230Vac).
R+
Modbus signal connection +for remote keyboard
Modbus communication
R-
Modbus signal connection -for remote keyboard
GNDR
Modbus ground reference terminal connection for remote keyboard
12V+
Remote keyboard power supply (12V, 50Hz, 500mA)
Output for 12Vac, 50Hz power supply
12V-
Remote keyboard power supply (12V, 50Hz, 500mA)

MEX VS Chillers and inverter air / water heat pumps with axial fans
17
SE/SE
Programmable analog input with sensor NTC-10kΏat 25°C β3435.
Or voltage-free digital input
Analog or digital input
AEHN
Terminal for neutral line of (230Vac)
Under-voltage output single phase 230Vac,
50Hz, 5A resistive, 1A inductive.
AEH
Terminal of phase line of (230Vac).
SAN/SAN
Programmable analog input with sensor NTC-10kΏat 25°C β3435.
Or voltage-free digital input
Analog or digital input
DO4N
Terminal for neutral line of single phase power supply (230Vac).
Under-voltage output single phase 230Vac,
50Hz, 5A resistive, 1A inductive.
Can be used in the versions without KA
DO4
Terminal for phase line of (230Vac).
DO5N
Terminal for neutral line of (230Vac).
Under-voltage output single phase 230Vac,
50Hz, 5A resistive, 1A inductive.
Can be used in the versions without KA
DO5
Terminal for phase line of (230Vac).
SW/SW
Input for summer/winter mode commutation from remote control panel (to
activate this function, please see corresponding paragraph in the control
manual)
Voltage-free digital input
onoff /onoff
on/off remote input
(closed = unit is ON / open =uniti s OFF)
Voltage-free digital input
0-10V+
Signal input: 0-10V (+) for set point adjustment
Analog input (ST10)
0-10V-
Signal input: 0-10V (-) for set point adjustment
7.8.2 Terminal block and the electric box
The following illustration shows the the removal procedure of the coping plate for the models 112 RH/115 RH, but the same
procedure is applicable for the other models
1.Remove the screws connecting the top plate. Two for each side of the unit and other two
crews connecting the top plate with the hole-cable plate holder. (For the small sizes, there is
only one fixing screw in the controller’s lateral part of the unit)
2.Remove the screws connecting the cover plate of the electric box then proceed to connect
wire to the terminal block.
3.Insert the cables PG cable glands located on the side of the unit to take them outside the unit
4.Close the electric box and the top panel of the unit with their fixing screws.
The above operations must be done after turning off the unit and disconnecting
it from the power supply (by mean of an appropriate disconnecting switch
which should be already mouted by the installer).
Operations to be performed by qualified personnel.
Remove the top cover without taking away the holder of hole-cabe plate.
The work is completed, please fix all the removed plates then tighten all screws
and washers (if expected).
8START UP
Before start-up:
Check out the availability of the supplied wiring diagrams and manuals of installed apparatus.
Check out the availability of the electrical and hydraulic diagrams of the plant in which the unit is installed.
Check that the shut-off valves of the hydraulic circuits are open.
Verify that the hydraulic circuit has been charged under pressure and air vented.
Check out that all water connections are properly installed and all indications on unit labels are observed.
Ensure that arrangements have been provided to drain the condensate.
Check out that all power cables are properly connected and all terminals are hardly fixed.
Check that electrical connections are carried out according to the norms in force including grounding.
Check out that the voltage is the one indicated in the unit labels.
Make sure the voltage is within the limits (±10%) of tolerance range.
Check out that crankcase heaters are powered correctly.
Check out that there is no refrigerant leakage.
Check out that all the cover panels are installed in the proper position and locked with fastening screws before start up.

MEX VS Chillers and inverter air / water heat pumps with axial fans
18
WARNING: The unit must be connected to the electrical network and should be in STAND-BY mode (powered) closing
the general switch in order to operate the crankcase heaters of the compressor for a minimum of 12 hours before
start up. (the heaters are automatically powered when the main switch is switched off). The crankcase heaters are
working properly if, after some minutes, the temperature of crankcase’s compressor is about 10°C ÷ 15°C higher than
ambient temperature.
WARNING: The weight of the pipes doesn’t load unit structure.
WARNING: Never switch off the unit (for a temporary stop) by switching off the main switch: this component should
be used to disconnect the unit from the power supply only for lengthy stoppages (e.g. seasonal stoppages). Besides,
failing the power supply, the crankcase’s heaters are not supplied thus resulting in a possible breakdown of the
compressors once the unit is switched on.
WARNING: Do not modify the internal wiring of the unit otherwise the warranty will terminate immediately.
WARNING: The summer/winter operating mode have to be selected at the beginning of the related season. Frequent
and sudden changes of this seasonal operating mode have to be avoided in order to prevent severe damages to
compressors.
WARNING: When you first install and start-up the unit make sure that the unit is working properly in both cooling
and heating modes.
9SHUTDOWNS FOR LONG PERIODS
The types of shutdown depends on the weather of the site where the unit is installed and on the period of the stop. The antifreeze
system, if it’s installed, stay on work also with the on-board control unit in “OFF” position.
If the time of stop is long and the temperature is low, we recommend to drain the hydraulic circuits or use a mixture of water and
glycol.
Drain the hydraulic circuits and shutdown the unit with this passage:
Turn off the unit by placing the switch of each unit to "OFF" position.
Close the water valves.
Place the general differential circuit breaker on "OFF" position, if it is installed upstream of the system.
If the temperature drops below 0°C there is serious danger of frost: add a mixture of water and glycol in the
plant, otherwise drain the hydraulic circuits of the plant and of the heat pump.
WARNING: the operation, although it was transient, with water temperatures below +5°C is not guaranteed on
the basis of the limits set out in Paragraph 15.4. Before you turn the unit on after a long off period, make sure
that the temperature of the mixture of water and glycol is higher than or at least equal to + 5°C.
10 MAINTENANCE AND PERIODICAL CONTROLS
WARNING: All the operations described in this chapter HAVE TO BE CARRIED OUT BY TRAINED STAFF ONLY.
Before any operation or before entering the inner components of the unit, be sure that the power supply is
disconnected. The compressor’s heads and discharge piping are usually at high temperature levels. Be very
careful when operating in their surroundings. Aluminium coil fins are very sharp and can cause serious wounds.
Be very careful when operating in their surroundings. After maintenance operations, re-install the cover panels,
and fix them by means of screws.
The refrigerant circuits must not be filled with different gas other than that indicated on the nameplate. The use
of a different refrigerant can cause severe damage to the compressor.
It’s forbidden to use oils other than those specified in this manual. The use of a different oil can cause serious
damage to the compressor.
The temperatures of heads and discharge piping of the compressor are usually high.
Be careful when working near condensing coils.
The aluminum fins are very sharp and can cause serious injuries.
After the maintenance operations, close the panels tightly with the fastening screws.
Be sure that only trained and qualified personnel to perform maintenance operation and periodical inspections on
the equipment. The EU Regulation 517/2014 establishes that users should assign a qualified personnel to be
responsible to regularly carry out inspections of the facilities, to perform tightness test and elimating eventual
leakages within the shortest possible time. Also has to check the obligatoriness and the necessary documentation
about the Regulation (EU) No 517/2014 and its subsequent amendment or repeal.

MEX VS Chillers and inverter air / water heat pumps with axial fans
19
It is a good rule to carry out periodic checks in order to verify the proper operation of the unit.
OPERATION
1 month
4 month
6 month
Filling the water circuit.
x
Presence of bubbles in the water circuit.
x
Check out that safety and control devices work correctly.
x
Check out possible oil leakage from compressor.
x
Check out possible water leakages from the hydraulic circuit.
x
Check out the proper working of the flow switches.
x
Check out that the crankcase electric heaters are properly supplied and functioning.
x
Clean the metallic filters of the hydraulic circuit.
x
Clean the finned coil by means of compressed.
x
Check out that all the terminals on the electric board as well as on the terminals of the
compressor are properly fixed.
x
Tightening of water connections.
x
Check out the tightening and the balancing of the fan blades.
x
Correct voltage.
x
Correct absorption.
x
Check the refrigerant charge.
x
Check the operating pressure, and superheat and subcooling.
x
Check of the efficiency of circulation pump.
x
Check the expansion tank.
x
If the unit should be out of service for a long period, discharge water from the piping and from
heat exchanger. This operation is necessary if, during seasonal stoppages, ambient
temperature is expected to go down below the freezing point of the employed fluid.
x
10.1 ENVIRONMENTAL PROTECTION
According to the norms dealing with the use of depleting stratospheric ozone substances, it is forbidden to release refrigerants
fluids in the atmosphere. They have to be collected and delivered to the seller or to proper gathering points at the end of their
operating life. Refrigerant R410A is mentioned among controlled substances and for this reason it has to be subjected to the
mentioned norms. A particular care is recommended during service operations in order to reduce as much as possible any
refrigerant loss.
11 APPLIANCE RECYCLING
Once the unit is arrived at the end of its life cycle and needs to be removed or replaced, the following operations are
recommended:
•the refrigerant has to be recovered by trained people and sent to proper collecting centre;
•compressors’ lubricating oil has to be collected and sent to proper collecting centre;
•the frame and the various components, if not serviceable any longer, have to be dismantled and divided according to their
nature, particularly copper and aluminium, which are present in conspicuous quantity in the unit. These operations allow easy
material recover and recycling process, thus reducing the environmental impact.
The user is responsable of the proper disposal of this product, according to national regulations in the country of destination of
the appliance. For more information you should contact the installation company or local competent authority.
An incorrect decommissioning of the appliance may create serious environmental damage and endanger people’s
safety. Therefore, it’s recommended that the unit shall be disposed only by authorized persons and technical training
who have followed training courses recognized by the competent authorities.
It is required to follow the same precautions described in the previous paragraphs.
Pay special attention during the disposal operation of the refrigerant gas.

MEX VS Chillers and inverter air / water heat pumps with axial fans
20
12 TECHNICAL DATA
TECHNICAL CHARACTERISTICS
Unit
Model MEX VS
15 RH
16 RH
18 RH
19 RH
Electric data
Power supply
230V/1/50Hz
230V/1/50Hz
Maximum power input
kW
3,3
4,8
5,1
6,1
Maximum current input
A
14,4
21,2
22,4
26,9
Cooling
Cooling capacity (min./nom./max.) (1)
kW
3,65 / 6,87 / 7,56*
4,65 / 8,52 / 9,12*
5,4 / 10 / 11,35*
5,4 / 11,9 / 13,1*
Power input (1)
kW
1,69
2,18
2,26
2,65
E.E.R. (1)
W/W
4,06
3,91
4,43
4,49
Cooling capacity (min./nom./max.) (2)
kW
2,32 / 5,07 / 5,58*
2,95 / 6,12 / 6,73*
3,27 / 7,56 / 8,83*
3,27 / 8,49 / 9,6*
Power input (2)
kW
1,74
2,11
2,43
2,74
E.E.R. (2)
W/W
2,91
2,90
3,11
3,10
SEER(5)
W/W
3,59
3,61
4,63
4,73
Heating
Heating capacity (min./nom./max.) (3)
kW
2,78 / 6,57 / 7,23*
3,54 / 8,01 / 8,81*
4,69 / 10 / 10,8*
4,69 / 12,1 / 12,7*
Power input (3)
kW
1,47
1,85
2,26
2,89
C.O.P. (3)
W/W
4,47
4,33
4,43
4,19
Heating capacity (min./nom./max.) (4)
kW
2,24 / 6,15 / 6,76*
2,85 / 7,92 / 8,71*
3,9 / 9,51 / 10,3*
3,9 / 11,3 / 12,1*
Power input (4)
kW
1,83
2,40
2,74
3,32
C.O.P. (4)
W/W
3,36
3,31
3,47
3,41
SCOP (6)
W/W
3,84
3,83
4,24
4,31
Energy efficiency water at 35°C/55°C
Class
A++ / A+
A++ / A+
A++ / A+
A++ / A+
Compressor
Type
Twin Rotary
DC Inverter
Twin Rotary
DC Inverter
Twin Rotary
DC Inverter
Twin Rotary
DC Inverter
Number
1
1
1
1
Refrigerant oil (type, quantity)
mL
ESTER OIL VG74, 670
ESTER OIL VG74, 670
ESTER OIL VG74,
1000
ESTER OIL VG74, 1000
Fan motor
Type
Brushless DC motor
Brushless DC motor
Brushless DC motor
Brushless DC motor
Number
1
1
1
1
Refrigerant
Type
R410A
R410A
R410A
R410A
Refrigerant quantity (11)
kg
2,05
1,9
3,8
3,8
Quantity of CO2equivalent (11)
ton
5,28
4,0
7,9
7,9
Design Pressure (high/low)
MPa
4,2 / 2,7
4,2 / 2,7
4,2 / 2,7
4,2 / 2,7
Circulator
Water flow rate (3)
m3/h
1,13
1,38
1,72
2,08
Available head pressure (3)
kPa
44,6
34,5
39,4
34,2
Rated power input (3)
kW
0,045
0,045
0,06
0,075
Max power input
kW
0,045
0,045
0,06
0,075
Max. current input
A
0,44
0,44
0,58
0,6
Energy Efficiency Index (EEI) circolatore
≤ 0,20
≤ 0,20
≤ 0,20
≤ 0,21
Hydraulic circuit
Expansion vessel
L
1
1
1
1
Hydraulic connections
inch
1” M
1” M
1” M
1” M
Minimum volume of water (7)
L
31
37
46
51
Noise level
Sound power (8)
dB(A)
62,0
62,5
63,0
63,5
Sound pressure at 1 m (9)
dB(A)
54
54,5
55
55,5
Sound pressure at 10 m (9)
dB(A)
34
34,5
35
35,5
Dimensions and
weight
Dimensions (LxDxW)
mm
925 x 785 x 380
925 x 785 x 380
1047 x 913 x 465
1047 x 913 x 465
Max. Packing dimensions (LxDxW) (10)
mm
995 x 944 x 415
995 x 944 x 415
1120 x 1080 x 520
1120 x 1080 x 520
Operating weight
kg
67
67,5
97
97
Net/Gross weight
kg
63,4 / 71,4
63,4 / 71,4
95,5 / 102
95,5 / 102
Operating conditions:
(1) Cooling: Outdoor air temperature 35°C; inlet/outlet water temperature 23/ 18°C.
(2) Cooling: Outdoor air temperature 35°C; inlet/outlet water temperature 12/7°C.
(3) Heating: Outdoor air temperature 7°C DB 6°C WB; inlet/outlet water temperature 30/35°C.
(4) Heating: Outdoor air temperature 7°C DB 6°C WB; inlet/outlet temperature 40/45°C.
(5) Cooling: Water temperature inlet/outlet 7/12°C.
(6) Heating: in average climate condition; Tbiv=-7°C; water temperature inlet/outlet 30/35°C.
(7) Calculated for a decrease of the water temperature of the plant with 10°C with a defrosting cycle of 6 minutes.
(8) Sound power heating mode condition (3); the value is determined respecting the measurements taken in accordance with the regulations UNI EN ISO
9614-2, in compliant with the Eurovent certification.
(9) Sound pressure level obtained with internal measurements made in accordance with ISO 3744, in case of the sound source located in free field positioned over
a reflecting plane.
(10) Packaging height including the pallet: in particular, the pallet height, for the models 15 RH/16 RH is 117mm, and for the models 18 RH/19 RH is 126mm.
(11) The data are only indicative and subject to change. For the correct data, refer to the technical label sticked on the unit.
(*) activating the Max Hz function.
The Power inputs include all circuit components such as fan motors, pumps, valves and controller, the test data is obtained according to EN 14511: 2013.