Itelco-Clima units MQH4 Installation and Maintenance Manual

Brand: Itelco-Clima units

Model: MQH4

Category: Heat pumps

Type: Installation and Maintenance Manual

English

Air cooled water chillers and air-to-water reverse cycle heat pumps

Refroidisseurs de liquide à condensation par air et pompes à chaleur

réversibles air-eau

Installation and maintenance manual

Manuel d’installation et de maintenance

IOM MQLH-N.1GBF

Date : November / Novembre 2005

Supersedes / Annule et remplace : None

MQL/MQH 4 ÷ 17

4.5



16.5 kW

4.6



18.4 kW

Français

Page 1

Table of contents

English

1 FOREWORD

1.1 Introduction 2

1.2 Warranty 2

1.3 Emergency stop/Normal stop 2

1.4 An introduction to this manual 2

2 SAFETY

2.1 Foreword 3

2.2 Definitions 3

2.3 Access to the unit 4

2.4 General precautions 4

2.5 Precautions against residual risks 4

2.6 Precautions during maintenance

operations 5

2.7 Safety labels 6

2.8 Safety regulations 7

3 TRANSPORT, LIFTING

AND POSITIONING

3.1 Inspection 10

3.2 Unit Handling 10

3.3 Anchoring 10

3.4 Storage 10

4 INSTALLATION

4.1 Installation advices 11

4.2 Water connections 13

4.3 Pressure Drop in Tubes and

Accessories 14

4.4 Hydraulic connection 14

4.5 Principle diagram of water circuit

4.6 Draining the defrosting waste water

(for heat pump unit only) 14

4.7 Power supply 15

4.8 Electrical connections 15

5 START-UP

5.1 Preliminary check 16

5.2 Start-up 16

5.3 Checking the operation 17

5.4 Delivery to the customer 17

6 MINICHILLER CONTROL

6.1 Operating instructions 18

6.2 Failure Diagnostics 19

7 GENERAL DESCRIPTION

7.1 Introduction 20

7.2 General specifications 20

7.3 Compressors 21

7.4 Coolant Circuit 21

7.5 Water-exchanger 21

7.6 Air exchanger 21

7.7 Fans 21

8 TECHNICAL DATA

8.1 Technical Data 24

8.2 Unit Electrical Data 28

8.3 Overall dimensions 30

8.4 Clearances 31

9 MAINTENANCE

9.1 General requirements 32

9.2 Planned maintenance 32

9.3 Refrigerant charge 33

9.4 Compressor 33

9.5 Condenser 33

9.6 Fans 33

9.7 Dehydrating filter 33

9.8 Thermostatic expansion valve

(only MQL-MQH 4-8) 34

9.9 Evaporator 34

10 TROUBLESHOOTING 35

11 SPARE PARTS

11.1 Spare parts list 37

11.2 Oil for compressors 37

11.3 Wiring diagram 37

12 DISMANTLING, DEMOLITION

AND SCRAPPING

12.1 Generalities 38

Table of contents

Manuale MQL-MQH 10.6.2005 12:25 Pagina 1

Page 2

Foreword

1 FOREWORD

1.1 Introduction

Itelco-Clima units, manufactured to state-of-the-art de-

sign and implementation standards, ensure top per-

formance, reliability and fitness to any type of air-

conditioning system.

These units are designed for cooling water or gly-

coled water* (and for water heating in heat pump

models) and are unfit for any purposes other than

those specified in this manual.

This manual includes all the information required for

a proper installation of the units, as well as the rele-

vant operating and maintenance instructions.

It is therefore recommended to read this manual

carefully before installation or any operation on the

machine. The chiller installation and maintenance

must be carried out by skilled personnel only (where

possible, by one of Itelco-Clima’s Authorised Service

Centers).

The manufacturer may not be held liable for any

damage to people or property caused by improper

installation, start-up and/or improper use of the unit

and/or failure to implement the procedures and in-

structions included in this manual.

1.2 Warranty

These units are delivered complete, tested and ready

for being operated. Any form of warranty will be-

come null and void in the event that the appliance is

modified without Itelco-Clima’s preliminary written

authorisation.

This warranty shall apply providing that the installa-

tion instructions have been complied with (either is-

sued by Itelco-Clima, or deriving from the current

practice).

In order for this warranty to be valid, the following

conditions shall be met:

hMaintenance must be performed only by skilled

personnel - from one of Itelco-Clima’s Authorised

After-Sales Centers.

hUse only original Itelco-Clima spare parts.

hCarry out all the planned maintenance provided

for by this manual in a timely and proper way.

Failure to comply with any of these conditions will

automatically void the warranty.

1.3 Emergency stop / Normal stop

The emergency stop of the unit can be enabled using

the master switch on the control panel (move down

the lever).

For a normal stop, press the relevant push-buttons.

To restart the appliance, follow the procedure de-

tailed in this manual.

1.4 An introduction to the manual

For safety reasons, it is imperative to follow the in-

structions given in this manual. In case of any dam-

age caused by non-compliance with these instruc-

tions, the warranty will immediately become null and

void.

Conventions used throughout the manual:

The Danger sign recalls your attention to a

certain procedure or practice which, if not

followed, may result in serious damage to

people and property.

The Warning sign precedes those proce-

dures that, if not followed, may result in seri-

ous damage to the appliance.

The Notes contain important observations.

The Useful Tips provide valuable informa-

tion that optimises the efficiency of the ap-

pliance.

This manual and its contents, as well as the docu-

mentation which accompanies the unit, are and re-

main the property of Itelco-Clima, which reserves

any and all rights thereon. This manual may not be

copied, in whole or in part, without Itelco-Clima’s

written authorization.

USEFUL TIPS

*Note: minimum leaving water temperature from evapo-

rator: + 5°C.

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Page 3

English

Safety

2 SAFETY

2.1 Foreword

These units must be installed in conformity with the

provisions of Machinery Directive 98/37/EC, Low

Voltage Directive 73/23/EC, Pressure Vessels Direc-

tive 97/23/EC, Electromagnetic Interference Direc-

tive 89/336/EC, as well as with other regulations

applicable in the country of installation. If these pro-

visions are not complied with, the unit must not be

operated.

The unit must be grounded, and no installa-

tion and/or maintenance operations may

be carried out before deenergising the elec-

trical panel of the unit.

Failure to respect the safety measures mentioned

above may result in electrocution hazard and fire in

the presence of any short-circuits.

Inside the heat exchangers, the compres-

sors and the refrigeration lines, this unit

contains liquid and gaseous refrigerant un-

der pressure. The release of this refrigerant

may be dangerous and cause injuries.

The units are not designed to be operated

with natural refrigerants, such as hydrocar-

bons. Itelco-Clima may not be held liable

for any problems deriving from the replace-

ment of original refrigerant or the introduc-

tion of hydrocarbons.

Itelco-Clima units are designed and manufactured

according to the requirements of European Standard

PED 97/23/EC (pressure vessels).

– The used refrigerants are included in group II (non-

hazardous fluids).

– The maximum working pressure values are men-

tioned on the unit’s data plate.

– Suitable safety devices (pressure switches and safe-

ty valves) have been provided, to prevent any

anomalous overpressure inside the plant.

– The vents of the safety valves are positioned and

oriented in such a way as to reduce the risk of con-

tact with the operator, in the event that the valve is

operated. Anyway, the installer will convey the dis-

charge of the valves far from the unit.

– Dedicated guards (removable panels with tools)

avoid contacts with potential dangerous zones.

The guards of the fans must be always

mounted and must never be removed be-

fore de-energising the appliance.

It is the User’s responsibility to ensure that

the unit is fit for the conditions of intended

use and that both installation and mainte-

nance are carried out by experienced per-

sonnel, capable of respecting all the recom-

mendations provided by this manual. It is

important that the unit is adequately sup-

ported, as detailed in this manual. Non-

compliance with these recommendations

may create hazardous situations for the

personnel.

The unit must rest on a base which meets

the characteristics specified in this manual;

a base with inadequate characteristics is

likely to become a source of serious injury

to the personnel.

The unit has not been design to withstand

loads and/or stress that may be transmitted

by adjacent units, piping and/or structures.

Each external load or stress transmitted to

the unit may break or cause breakdowns in

the unit’s structure, as well as serious dan-

gers to people. In these cases, any form of

warranty will automatically become null

and void.

The packaging material must not be dis-

posed of in the surrounding environment or

burnt.

2.2 Definitions

OWNER: means the legal representative of the com-

pany, body or individual who owns the plant where

Itelco-Clima unit has been installed; he/she has the

responsibility of making sure that all the safety regu-

lations specified in this manual are complied with,

along with the national laws in force.

INSTALLER: means the legal representative of the

company who has been given by the owner the job

of positioning and performing the hydraulic, electric

and other connections of Itelco-Clima unit to the

plant: he/she is responsible for handling and prop-

erly installing the appliance, as specified in this man-

ual and according to the national regulations in

force.

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Page 4

Safety

OPERATOR: means a person authorised by the own-

er to do on Itelco-Clima unit all the regulation and

control operations expressly described in this manu-

al, that must be strictly complied with, without ex-

ceeding the scope of the tasks entrusted to him.

ENGINEER: means a person authorised directly by

Itelco-Clima or, in all EC countries, excluding Italy,

under his full responsibility, by the distributor of Itel-

co-Clima product, to perform any routine and extra-

ordinary maintenance operations, as well as any

regulation, control, servicing operations and the re-

placement of pieces, as may be necessary during the

life of the unit.

2.3 Access to the unit

The unit must be placed in an area which can be ac-

cessed also by OPERATORS and ENGINEERS; oth-

erwise the unit must be surrounded by a fence at not

less than 2 meters from the external surface of the

machine.

OPERATORS and ENGINEERS must enter the fenced

area only after wearing suitable clothing (safety

shoes, gloves, helmet etc.). The INSTALLER personnel

or any other visitor must always be accompanied by

an OPERATOR.

For no reason shall any unauthorised personnel be

left alone in contact with the unit.

2.4 General precautions

The OPERATOR must simply use the controls of the

unit; he must not open any panel, other than the one

providing access to the control module.

The INSTALLER must simply work on the connections

between plant and machine; he must not open any

panels of the machine and he must not enable any

control.

When you approach or work on the unit, follow the

precautions listed below:

hdo not wear loose clothing or jewellery or any oth-

er accessory tat may be caught in moving parts

hwear suitable personal protective equipment

(gloves, goggles etc.) when you have to work in

the presence of free flames (welding operations) or

with compressed air

hif the unit is placed in a closed room, wear ear pro-

tection devices

hcut off connecting pipes, drain them in order to

balance the pressure to the atmospheric value be-

fore disconnecting them, disassemble connections,

filters, joints or other line items

hdo not use your hands to check for any pressure

drops

huse tools in a good state of repair; be sure to have

understood the instructions before using them

hbe sure to have removed all tools, electrical cables

and any other objects before closing and starting

the unit again

2.5 Precautions against residual risks

Prevention of residual risks caused by the

control system

hbe sure to have perfectly understood the operating

instructions before carrying out any operation on

the control panel

hwhen you have to work on the control panel, keep

always the operating instructions within reach

hstart the unit only after you have checked its perfect

connection to the plant

hpromptly inform the ENGINEER about any alarm

involving the unit

hdo not reset manual restoration alarms unless you

have identified and removed their cause

Prevention of residual mechanical risks

hinstall the unit according to the instructions provid-

ed in this manual

hcarry out all the periodical maintenance opera-

tions prescribed by this manual

hbefore opening any panelling of the machine,

make sure that it is secured to it by hinges

hdo not touch air condensation coils without wear-

ing protective gloves

hdo not remove the guards from moving elements

while the unit is running

hcheck the correct position of the moving elements’

guards before restarting the unit

Prevention of residual electrical risks

hconnect the unit to the mains according to the in-

structions provided in this manual

hperiodically carry out all the maintenance opera-

tions specified by this manual

hdisconnect the unit from the mains by the external

disconnecting switch before opening the electrical

board

hcheck the proper grounding of the unit before start-

hcheck all the electrical connections, the connecting

cables, and in particular the insulation; replace

worn or damaged cables

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Page 5

English

Safety

hperiodically check the board’s internal wiring

hdo not use cables having an inadequate section or

flying connections, even for limited periods of time

or in an emergency

Prevention of other residual risks

hmake sure that the connections to the unit conform

to the instructions provided in this manual and on

the unit’s panelling

hif you have to disassemble a piece, make sure that

it has been properly mounted again before restart-

ing the unit

hdo not touch the delivery pipes from the compres-

sor, the compressor and any other piping or com-

ponent inside the machine before wearing protec-

tive gloves

hkeep a fire extinguisher fir for electrical appliances

near the machine

hon the units installed indoor, connect the safety

valve of the refrigeration circuit to a piping net-

work that can channel any overflowing refrigerant

outside

hremove and leak of fluid inside and outside the unit

hcollect the waste liquids and dry any oil spillage

hperiodically clean the compressor compartment, to

remove any fouling

hdo not store flammable liquids near the unit

hdo not disperse the refrigerant and the lubricating

oil into the environment

hweld only empty pipes; do not approach flames or

other sources of heat to refrigerant pipes

hdo not bend/hit pipes containing fluids under pres-

sure

2.6 Precautions during maintenance

operations

Maintenance operations can be carried out by au-

thorised technicians only.

Before performing any maintenance operations:

hdisconnect the unit from the mains with the external

disconnecting switch

hplace a warning sign “do not turn on - mainte-

nance in progress” on the external disconnecting

switch

hmake sure that on-off remote controls are inhibited

hwear suitable personal protective equipment (hel-

met, safety gloves, goggles and shoes etc.)

To carry out any measurements or checks which re-

quire the activation of the machine:

hwork with the electrical board open only for the

necessary time

hclose the electrical board as soon as the measure-

ment or check has been completed

hfor outdoor units, do not carry out any operations

in the presence of dangerous climatic conditions

(rain, snow, mist etc.)

The following precautions must be always adopted:

hdo not scatter the fluids of the refrigeration circuit

in the surrounding environment

hwhen replacing an eprom or electronic cards, use

always suitable devices (extractor, antistatic

bracelet, etc.)

ho replace a compressor, the evaporator, the con-

densing coils or any other weighty element, make

sure that the lifting equipment is consistent with the

weight to be lifted

hin air units with independent compressor compart-

ment, do not access the fan compartment unless

you have disconnected the machine by the discon-

necting switch on the board and you have placed

a warning sign “do not turn on - maintenance in

progress”

hcontact Itelco-Clima for any modifications to the re-

frigeration, hydraulic or wiring diagram of the

unit, as well as to its control logics

hcontact Itelco-Clima if it is necessary to perform

very difficult disassembly and assembly operations

huse only original spare parts purchased directly

from Itelco-Clima or the official retailers of the com-

panies on the recommended spare parts list

hcontact Itelco-Clima if it is necessary to handle the

unit one year after its positioning on site or if you

wish to dismantle it.

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Page 6

Grounding connection - On the electrical

board, adjacent to the connection

Final Test Certificate -

Inside the external door

Fitting identification -

Adjacent to fittings

EIN - INLET

ENTRÉE - ENTRATA

AUS - OUTLET

SORTIE - USCITA

Safety

2.7 Safety labels

The labels below will be affixed to each unit in the indicated point:

Identification of the unit -

Outside, on the right-hand front column

Electrical warning

Adjacent to the master switch

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Page 7

Safety

2.8 Safety regulations

English

Refrigerant data

Toxicity Low

Contact with skin If sprayed, the refrigerant is likely to cause frost burns. If absorbed by

the skin, the danger is very limited; it may cause a slight irritation, and

the liquid is degreasing. Unfreeze the affected skin with water. Remove

the contaminated clothes with great care - in the presence of frost

burns, the clothes may stick to the skin. Wash with plenty of warm wa-

ter the affected skin.

In the presence of symptoms such as irritation or blisters, obtain med-

ical attention.

Contact with eyes

Ingestion

Inhalation

Recommendations

Prolonged exposure

Vapours do not cause harmful effects. The spraying of refrigerant may

cause frost burns. Wash immediately with a proper solution or with tap

water for at least 10 minutes, and then obtain medical attention.

Very unlikely - should something happen, it will cause frost burns.

Do not induce vomiting. Only if the patient is conscious, wash out

mouth with water and give some 250 ml of water to drink. Then, obtain

medical attention.

R407C: remarkable concentrations in the air may have an anaesthetic

effect, up to fainting. The exposure to considerable amounts may cause

irregular heartbeat, up to the sudden death of the patient. Very high

concentrations may result in the risk of asphyxia, due to the reduction in

the oxygen percentage in the atmosphere. Remove the patient to fresh

air and keep warm and at rest.

If necessary, give oxygen. In case of breathing difficulties or arrest, pro-

ceed with artificial respiration. In case of cardiac arrest, proceed with

cardiac massage. Then, obtain medical attention.

Semiotics or support therapy is recommended. Cardiac sensitisation

has been observed that, in the presence of circulating catecholamines

such as adrenalin, may cause cardiac arrhythmia and accordingly, in

case of exposure to high concentrations, cardiac arrest.

R407C: a study on the effects of exposure to 50,000 ppm during the

whole life of rats has identified the development of benign testicle tu-

mour. This situation should therefore be negligible for personnel ex-

posed to concentrations equal to or lower than professional levels.

Professional levels

Stability R407C: Not specified

R407C: Recommended threshold: 1000 ppm v/v - 8 hours TWA.

Conditions to avoid Do not use in the presence of flames, burning surfaces and excess hu-

midity.

Safety data: R407C

Hazardous reactions May react with sodium, potassium, barium and other alkaline metals.

Incompatible substances: magnesium and alloys with magnesium con-

centrations > 2%.

Hazardous decomposition

products R407C: Halogen acids produced by thermal decomposition and hy-

drolysis.

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Page 8

Safety

Respiratory system protection

Storage

Protective clothing

Accidental release measures

Disposal

Fire fighting information

Cylinders

Protective fire fighting

equipment

If you are in doubt about the concentration in the atmosphere, it is rec-

ommended to wear a respirator approved by an accident-prevention

Authority, of the independent or oxygen type.

Cylinders must be stored in a dry and fresh place, free from any fire

hazard, far from direct sunlight or other sources of heat, radiators etc.

Keep a temperature below 45°C.

Wear overalls, protective gloves and goggles or a mask.

It is important to wear protective clothing and a respirator. Stop the

source of the leak, if you can do this without danger. Negligible leaks

can be left evaporating under the sun, providing that the room is well

ventilated. Considerable leaks: ventilate the room. Reduce the leak with

sand, earth or other absorbing substances. Make sure that the liquid

does is not channelled into gutters, sewers or pits where the vapours

are likely to create a stuffy atmosphere.

The best method is recovery and recycling. If this method is not practi-

cable, dispose according to an approved procedure, that shall ensure

the absorption and neutralization of acids and toxic agents.

R407C: Not flammable in the atmosphere.

In case of fire, wear an independent respirator and protective clothing.

The cylinders, if exposed to fire, shall be cooled by water jets; other-

wise, if heated, they may explode.

Do not inhale concentrated vapours. Their concentration in the atmos-

phere should not exceed the minimum preset values and should be

maintained below the professional threshold. Being more weighty than

the air, the vapour concentrates on the bottom, in narrow areas. There-

fore, the exhaust system must work at low level.

General precautions

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Page 9

English

Safety

Refrigerant oil data Safety data: Polyolester oil (POE)

Classification

Contact with skin

Contact with eyes

Ingestion

Inhalation

Conditions to avoid

Protection of the respiratory

system

Protective clothing

Accidental release measures

Disposal

Fire fighting information

Cylinders

Fire fighting protective

equipment

Not harmful

May cause slight irritation. Does not require first aid measures. It is rec-

ommended to follow usual personal hygiene measures, including wash-

ing the exposed skin with soap and water several times a day. It is also

recommended to wash your overalls at least once a week.

Wash thoroughly with a suitable solution or tap water.

Seek medical advice immediately.

Strong oxidising substances, caustic or acid solutions, excess heat.

May corrode some types of paint or rubber.

Use in well ventilated rooms.

Always wear protective goggles or a mask. Wearing protective gloves

is not mandatory, but is recommended in case of prolonged exposure

to refrigerant oil.

It is important to wear protective clothing and, especially, goggles.

Stop the source of the leak. Reduce the leak with absorbing substances

(sand, sawdust or any other absorbing material available on the mar-

ket).

The refrigerant oil and its waste will be disposed of in an approved in-

cinerator, in conformity with the provisions and the local regulations

applicable to oil waste.

In the presence of hot liquid or flames, use dry powder, carbon dioxide

or foam. If the leak is not burning, use a water jet to remove any

vapours and to protect the personnel responsible for stopping the leak.

The cylinders exposed to a fire will be cooled with water jets in case of

fire.

In case of fire, wear an independent respirator.

Manuale MQL-MQH 10.6.2005 12:26 Pagina 9

3 TRANSPORT, LIFTING

AND POSITIONING

Refrigerators are supplied assembled. The equip-

ment are full of refrigerant and oil (except to the con-

densing unit), in the quantity required for a proper

operation.

3.1 Inspection

When the unit is delivered, it is recommended to

check it carefully and to identify any damage oc-

curred during transportation. The goods are shipped

ex-factory, at the buyer’s risk. Check that the delivery

includes all the components listed in the order.

In case of damage, note it down on the carrier’s de-

livery note and issue a claim according to the instruc-

tions provided in the delivery note.

In the presence of any serious damage, that does not

affect the surface only, it is recommended to inform

Itelco-Clima immediately.

Please note that Itelco-Clima may not be held liable

for any damage to the equipment during transporta-

tion, even though the carrier has been appointed by

the factory.

3.2 Unit Handling

Sharp edges and coil surfaces are a poten-

tial hazard. Avoid contact with them.

Be careful to avoid rough handling of the unit. Do

not push or pull the unit anything other than the

base. Block the pushing vehicle away from the unit

to prevent damage to the sheet metal cabinet and

end frame (see picture 1).

Page 10

3.3 Anchoring

It is not essential to secure the unit to the foundations,

unless in areas where there is a serious risk of earth-

quake, or if the appliance is installed on the top of a

steel frame.

3.4 Storage

When the unit is to be stored before installation,

adopt a few precautions to prevent any damage or

risk of corrosion or wear:

hplug or seal every single opening, such as water

fittings

hdo not store the appliance in a room where the

temperature exceeds 50°C for the units using

R407C and, if possible, do not expose to direct

sunlight

hit is recommended to store the unit in a roof where

traffic is minimized, to prevent the risk of acciden-

tal damage

hthe unit must not be washed with a steam jet

htake away and leave to the site manager all the

keys providing access to the control board

Finally, it is recommended to carry out visual inspec-

tions at regular intervals.

Transport, Lifting and Positioning

Blocking required across

(full width)

Picture 1

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Page 11

English

Installation

4 INSTALLATION

4.1 Installation advices

Unit placement

The MQL/MQH water chillers are cooled by air.

Thereby, they must be installed in the open air, in

an area where the flow of air to and from the con-

denser coil must not be limited. A space restriction,

which reduces the air flow, will decrease the cool-

ing capacity, increase the power input and, in

some cases, prevent the unit from operating

because of an excess of condensation pressure.

The MQL/MQH water chillers are equipped with

propeller type condenser fan. Therefore, they will

not operate with ductwork on the fan outlet.

In case of installation in an area subject to be hit by

strong wind, direct effect of the wind on the dis-

charge surface of the fan should be avoided.

Care should be taken, at the time of installation, to

leave enough clearances around the unit for mainte-

nance works.

The minimum clearances are shown on picture 2

and must be considered, both to ensure that the unit

operates correctly and to allow easy access.

Picture 2

MQL

The units should be installed on a flat and hard,

preferably concrete base.

When fixing the unit, a slope of 1 cm/m is recom-

mended to allow draining of rain water.

Units MQL/MQH 4 and 6 cannot be

installed with advanced inclination to 10°.

For reverse cycle models, if the outdoor temperature

is likely to fall below +1 °C, provide a system to

prevent the condensates from freezing (e.g. heating

cord).

For installation in difficult climates, temperatures

below 0 °C, snow or humidity, it is recommended

to elevate the unit about 20 cm above the floor.

The plastic grille is used to protect the

operators from injury risks on heat

exchanger at the time of handling and

installation.

However, risks of clogging by freeze or

hoar frost can be occured on reverse cycle

units installed in cold or mountainous

regions and exposed to the elements.

To prevent all risks, a shelter is to be pro-

vided or simply remove the protective

grille.

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Page 12

Fixing dimensions

The fixing dimensions of the unit are shown on the

figure opposite. Vibration isolators are recommend-

ed for all roof mounted installation or wherever

vibration transmis-sion is a consideration.

Picture 3 shows the location of each isolator.

Installation

Maintenance access

After installation, each side of the unit must allow

easy access for periodic maintenance works.

The removal of panel 1 allows access to compres-

sor, refrigerant circuit as well as hydronic module.

The fan-motor assembly is accessible after removing

the panel 2 .

20 1142

1182

4xØ13

22,5 349 22,5

ARIA

Picture 3

Photo 1

Photo 2

Remark: The panel 1 is removable independently

of other panels and allows a start-up by maintain-

ing the operating characteristics of the unit.

panel 2

panel 1

Photo 3

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Page 13

English

4.2 Water connections

Water Piping

Local authorities can supply the installer with the

proper building and safety codes required for safe

and proper installation.

Install piping with minimum bends and

changes in elevation to minimize pressure

drop.

Consider the following when installing

water piping:

1. Vibration eliminators to reduce vibration and

noise transmission to the building. Check the free

volume expansion of the connection piping.

2. Shut-off valves to isolate the unit from the piping

system during unit servicing.

3. Manual or automatic air vent valves at the high-

est points of the chilled water piping.

4. A means of maintaining adequate system water

pressure (expansion tank or regulating valve).

5. Temperature and pressure indicators located at

the unit to aid in unit servicing.

6. To avoid all risks of penetration of for-

eign matters and to keep system perfor-

mance up, it is mandatory to install a

strainer at the inlet of the unit.

Protection from freezing

It is recommended to protect the water system from

freezing whatever the model used (cooling only or

reverse cycle). The table below shows the anti-

freeze concentration to be used depending on the

minimum outdoor temperature.

Installation

0 -5 -10 -15 -25 -30

10 20 30 40 50 60

Safety Differential Pressure Switch

A safety differential pressure switch (ref. 6) is facto-

ry mounted on water inlet piping of evaporator, in

order to ensure adequate water flow to evaporator

before starting up the unit.

It comes into operation in case of drop in water

flow owing to the fact that the pump failed to oper-

ate.

The safety differential pressure switch is the main

protective device of the machine.

It is not our policy to make recommenda-

tions on water treatment. The general con-

tractor or owner should contact a local

water treatment company regarding water

treatment. However, this topic is critical

and care should be taken to make sure it is

done properly to prevent problems related

to flow. A fouled water system will lead to

premature component failure.

Water connections could be damaged by

an important stress when screwing them.

Use a second spanner to compensate the

stress of tightening.

Minimum

outdoor temp. °C

Concentration

in %

Manuale MQL-MQH 10.6.2005 12:26 Pagina 13

* Maximum height 15 meters

Page 14

Installation

4.3 Pressure Drop in Tubes and

Accessories

To determine the appropriated pipe section, see

table n° 1 which shows the values of pressure drop

for various water flows and the diameter of stan-

dard copper pipes for hydraulic installations.

4.4 Hydraulic connection

The water inlet/outlet fittings shall conform to the in-

structions provided by the plates affixed neat the

connection points.

4.5 Principle Diagram

of Water Circuit

The MQL/MQH are to be connected with the termi-

nal units such as fan coil units, cassettes or wall

mounted units. Each terminal unit connected with

the MQL/MQH water chiller and provided with its

own control is therefore completely independent of

the chiller (see diagram of principle on the left).

* If the terminal unit is on a lower level than the

MQL/MQH water chiller, make sure the water

pressure in the chiller is at least 0.5 bar.

4.6 Draining the defrosting waste

water (for heat pump unit only)

When heat pump units work in heating mode, dur-

ing defrosting cycles, they may discharge water

from the base.

The heat pump units must be installed in positions

where the defrosting water cannot create any dam-

age.

Table n° 1

Pressure drop (mm WG / m)

Velocity (m/s)

Nominal diameter

13 x 15 16 x 18 20 x 22 26 x 28 33 x 35

Flow

(l/h)

600 172

1,25 65

0,83 22

0,53

400 86

0,84 32

0,55

800 286

1,67 108

1,11 37

0,71 10

0,42

1000 158

1,38 55

0,88 16

0,52 5

0,32

1200 216

1,65 75

1,06 22

0,63 7

0,39

1400 284

1,93 99

1,24 28

0,73 9

0,45

1600 124

1,41 36

0,84 12

0,52

1800 133

1,59 44

0,94 14

0,58

2000 184

1,77 52

1,04 17

0,65

2200 217

1,94 62

1,15 20

0,71

2400 254

2,12 72

1,25 23

0,78

Tabella n° 2

1 mm WG = 9,81 Pa.

Equivalent length (m)

Nominal diameter

0,2 0,2 0,3 0,4 0,5Ball check valve

0,2 0,2 0,26 0,35 0,545° Bend

0,4 0,4 0,5 0,7 1,090° Bend

0,3 0,3 0,4 0,6 0,8690° Curve

0,8 0,8 1,0 0,5 2,0T-piece

13 x 15 16 x 18 20 x 22 26 x 28 33 x 35

Accessories

The grey area shows pressure drop in mm of water

gauge/m and the velocity in m/s recommended for

various flows and diameters.

Intermediate values are determined through interpo-

lation.

Values outside the grey area correspond to exces-

sive pressure drops and should be avoided.

Table n° 2 shows the equivalent length pipe with

the same diameter, of a few common accessories

for this type of installation.

Manuale MQL-MQH 10.6.2005 12:26 Pagina 14

4.7 Power supply

Before carrying out any operations on the

electrical system, make sure that the unit is

deenergised.

It is important that the appliance is ground-

ed.

The company in charge of the installation

shall conform to the standards applicable to

outdoor electrical connections.

Itelco-Clima may not be held liable for any damage

and/or injury caused by failure to comply with these

precautions.

The unit conforms to EN 60204-1.

The following connections shall be provided:

hA link for the power supply and the earth connec-

tion

hThe electrical distribution system shall meet the

power absorbed by the appliance.

hThe disconnecting and magnetothermal switches

must be sized to control the starting current of the

unit.

hThe power supply lines and the insulation devices

must be designed in such a way that every line in-

dependent.

hIt is recommended to install differential switches,

to prevent any damage caused by phase drops.

hThe fans and compressors are supplied through

contactors controlled from the control panel.

hEach motor is provided with an internal safety

thermal device and external fuses.

hThe power supply cables must be inserted into

dedicated openings on the front of the unit, and

the will enter the electrical board through holes

drilled on the bottom of the board.

Page 15

English

Installation

4.8 Electrical connections

The unit must be installed on site according to the

Machinery Directive (98/37/EC), the Low Voltage Di-

rective (73/23/EC), the Electromagnetic Interference

Directive (89/336/EC) and the usual procedures and

standards applicable in the place of installation. The

unit must not be operated if its installation has not

been carried out according to the instructions provid-

ed in this manual.

The power supply lines must consist of insulated cop-

per conductors, dimensioned for the maximum ab-

sorbed current.

Connection to terminals must be performed accord-

ing to the diagram of connections provided in this

manual and according to the wiring diagram which

accompanies the unit.

Before connecting the power supply lines,

check that the available voltage value does

not exceed the range specified in the Elec-

tric Data (Chapter 8).

For 3-phase systems, check also that the unbalance

between the phases does not exceed 2%. To perform

this check, measure the differences between the volt-

age of each phase couple and their mean value dur-

ing operation. The maximum % value of these differ-

ences (unbalance) must not exceed 2% of the mean

voltage. If the unbalance is unacceptable, contact

the Energy Distributor to solve this problem.

Supplying the unit through a line whose un-

balance exceeds the permissible value will

automatically void the warranty.

It’s recommended to check the correct se-

quence of the three supply phases R-S-T- be-

fore the unit start up.

Manuale MQL-MQH 10.6.2005 12:26 Pagina 15

Page 16

Start-up

5 START-UP

On MQL-MQH Chiller the first start up must

be done by an authorized technician. Fol-

lowing suggestions should be applied in or-

der to do the operation properly.

5.1 Preliminary check

The checks listed below shall be performed before

starting the unit .

hCheck the section of power supply and grounding

cables; make sure that terminals are tightened and

check the correct operation of contactors, with the

master switch open.

hCheck that any voltage and phase variation in the

power supply does not exceed the prefixed thresh-

olds.

hCheck that the components of the external water

circuit (user equipment, filters, power supply tank

and reservoir, if any) have been installed proper-

ly, and according to the manufacturer’s instruc-

tions.

hCheck the filling of the hydraulic circuits, and

make sure that the fluid circulation is correct, with-

out any trace of leaks and air bubbles.

hCheck that the direction of rotation of the pumps is

correct, and that fluids have been circulating for at

least 4 hours. Then, clean the filters on the suction

side of the pumps.

hAdjust the liquid distribution network in such a way

that the flow rate is within the specified range.

hCheck that the water quality is up to the specifica-

tions.

hCheck that oil heaters, if any, have been turned on

at least 4 hours before (It is mandatory if the tem-

perature is under 15°C).

5.2 Start-up

Start-up sequence:

hTurn on the main switch disconnector (at least 4

hours before).

hCheck that the oil in the compressor has reached

the requested temperature (the minimum tempera-

ture outside the pan must be approx. 40°C) and

that the auxiliary control circuit is energised.

hCheck the operation of all the external equipment,

and make sure that the control devices of the plant

are properly calibrated.

hStart the pump and check that the water flow is

correct.

hSet the desired fluid temperature on the control

board.

hStart the appliance (see Chapter 6).

hCheck the correct direction of rotation of compres-

sors. Scroll compressors cannot compress the re-

frigerant when they rotate in the opposite direc-

tion. To make sure that they are rotating in the cor-

rect direction, simply check that, just after the start-

up of the compressor, the pressure drops on the LP

side and rises on the HP side. Furthermore, if a

scroll compressor rotate in the opposite direction,

there is a considerable rise in the sound level of

the unit, as well as in a dramatic reduction of cur-

rent absorption compared to normal values. In

case of wrong rotation, the scroll compressor can

be definitely damaged.

Manuale MQL-MQH 10.6.2005 12:26 Pagina 16

Page 17

English

Start-up

5.3 Checking the operation

Check the following:

hThe temperature of the water entering the evapo-

rator.

hThe temperature of the water leaving the evapora-

tor.

hThe level of the water flow rate in the evaporator,

if possible.

hThe current absorption upon the start of the com-

pressor and in case of stabilised operation.

hThe fan’s current absorption.

Check that the condensing and evaporation temper-

atures, during operation at high and low pressure

detected by the pressure gauges of the refrigerant,

are within the following range:

(On the units not provided with HP/LP pressure

gauges for the refrigerant, connect a pressure gauge

to the Schreader valves on the refrigeration circuit).

5.4 Delivery to the customer

hTrain the user according to the instructions provid-

ed in Section 6.

Approx. 15 to 21°C above the

temperature of the air entering the

condenser, for R407C units.

Approx. 2 to 4°C below the tem-

perature of the leaving chilled wa-

ter, for R407C units.

HP side

LP side

Manuale MQL-MQH 10.6.2005 12:26 Pagina 17

Doing this, you can display the shop setting,

which is 12 °C. This setting can be increased or

decreased by scrolling its value up or down,

through the relevant keys.

Once the desired value has been displayed, sim-

ply press both keys for 2 seconds to accept it and

to go back to the previous level. If you scroll the

text, the “HEA” message is displayed and the

heating set point can be modified through the

same procedure adopted to modify the cooling

set point.

At the end of the setting process, you can go back

to the first level, by holding both keys down for

2 seconds, as described in the paragraph “User

Interface”.

4) To display other useful temperatures, go

to level 1 as described above and then scroll the

display up until the “tp” message is displayed;

then, repeat the procedure in order to go to the

lower level. At this point, scroll the display until

the t01, t02, t03 messages appear.

Going to the next level, while the t02 message is

being displayed, allows you to display the leav-

ing water temperature, while repeating this opera-

tion when the tp03 message appears allows you

to display the surface temperature of the coil.

5) The unit is shop-preset for summer/winter switch-

ing with the keyboard. If a remote summer/

winter switching contact has been provided,

it is necessary to switch the H27 software parame-

ter to re-configure the unit accordingly.

To do this, press the two keys at the same time, so

as to go to the upper level, and then scroll the dis-

play up until the “Par” message appears. Press

the two keys again at the same time, so as to go to

the upper level, and then scroll the display up until

the “Cnf” message appears; then repeat this oper-

ation to go to the upper level.

Once you have reached this level, scroll the dis-

play up until the “H27” message appears, and

then press the two keys again to reach the lower

level.

At this point, modify the setting of the parameter

from 0 to 1. Confirm the change and repeat the

procedure (holding the keys down for two sec-

onds), in order to go back to the first level.

Page 18

6 MINICHILLER CONTROL

6.1 Operating instructions

6.1.1 Before start-up

Before starting the equipment:

1) Turn on the master switch of the power line.

2) For an ideal heating of the oil in the compressor’s

cup and for a proper removal of the refrigerant

from the oil, the operation described in sub-para-

graph 1) above should be performed several

hours before the actual start-up of the equipment.

6.1.2 Starting and using the Unit

To properly use the unit in full safety, please read

and understand the instructions provided below.

1) To start the unit, press the key for two

seconds ; the unit will stop if you carry out the

same operation while it is running. When the

equipment does not work, the control system’s dis-

play shows a red hyphen or the message “E00”,

if a remote Run/Stop contact has been provided.

2) If the unit is of the heat pump type, the key

makes it possible to select either the cooling or the

heating mode.

When you press this key, the mode cyclically

switches from standby to cooling, heating, stand-

by etc. The cooling mode is highlighted by the

lighting-up of the LED positioned under the

ideogram, while the heating mode is highlighted

by the lighting-up of the LED positioned under the

ideogram.

3) To modify the set-points, press both keys at

the same time.

When the “Set” message appears on the display,

this operation must be repeated to go to the next

level. Scroll the text on the display up or down, in

order to display the “Coo” and “HEA” messages

alternatively. The heating set point can be modi-

fied by pressing both keys at the same time, so as

to switch to the next level.

Control System

Manuale MQL-MQH 10.6.2005 12:26 Pagina 18

Page 19

English

Control System

6) In case of summer/winter switching through re-

mote contact, the unit will operate in cool-

ing mode when this contact is closed and

in heating mode when it is open.

If the unit is powered by 3-phase current, it

is essential that the compressor turns in the

correct direction. The direction of rotation

of scroll compressors is fixed. The direction

of rotation is wrong when, while the unit is

working, you can feel:

• an anomalous noise in the compressor

• the lack of the correct differential between dis-

charge pressure and suction pressure (i.e. if

the discharge pressure is just above the suc-

tion pressure).

If you exchange the connections of two out of

three phases, the compressor inverts the direc-

tion of rotation and these phenomena disappear

suddenly.

6.2 Failure Diagnostics

Alarms Table

Code

Meaning Possible cause Corrective action

E00 Remote On-Off Turning off of the remote On-Off

contact Turn on the remote contact

E01

Excessive discharge pressure

(automatic energizing, just an in-

tervention in an hour)

1. The air circuit is clogged

Altered calibration of the dis-

charge pressure contro

3. HP set point setting error

Excessive refrigerant charge

5. Fan malfunctioning

6. Dirty refrigerant/air exchang-

7. Off-range operation

8. Low water flow rate (in heat-

ing mode)

9. Dirty water filter (in heating

mode)

1. Remove any obstacle

2. Set-up the regulator

3. Increase the set point

4. Check the charge

5. Check the functioning and connection

of the fan’s motor

6. Clean the exchanger

7. Ensure compliance with the working

range

8. Adjust the flow rate

9. Clean the air filter

E02 Insufficient discharge pressure

(automatic energizing until the

first two interventions in an hour)

1. Low water flow rate

2. Dirty refrigerant/air

exchanger

3. Clogged refrigerant filter

4. Low discharge pressure

5. Refrigerant leaks

1. Adjust the flow rate

2. Clean the exchanger

3. Replace the refrigerant filter

4. Check the set point of the discharge

pressure

5. Identify and remove any leaks

E05 Antifreezing protection

(automatic energizing until the

first two interventions in an hour)

1. Low water flow rate 1. Adjust the flow rate

E06 Failure of sensor ST2

(water outlet) Occurs when ST2 is interrupted,

in short-circuit or off-range Check ST2 and replace it if necessary

E07 Failure of sensor ST3

(refrigerant/water exchanger) Occurs when ST3 is interrupted,

in short-circuit or off-range Check ST3 and replace it if necessary

E41 Alarm is automatically resetted

up to first three events occurring

in one hour.

No water flow rate Check the differential pressure switch, the

pump and the hydraulic system

Manuale MQL-MQH 10.6.2005 12:26 Pagina 19

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Itelco-Clima units MQH4 Installation and Maintenance Manual

Brand: Itelco-Clima units

Model: MQH4

Category: Heat pumps

Type: Installation and Maintenance Manual

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Itelco-Clima units MQH4 Installation and Maintenance Manual

Itelco-Clima units MQH4 Installation and Maintenance Manual

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