Liebert CBH 028, CBH 020, CLH 023, CBH 025, CBH 017 Service Manual

S [017-032]

HIGH PERFORMANCE AIR COOLED CHILLER

SERVICE MANUAL

English

Cod. 272902

Rev. 25.05.2005

Issued by T.D.Service

Caution

It is recommended that:

S the manual is retained for the entire service life of the machine;
S the user reads the manual carefully before carrying out any operations on the machine;
S the machine is used exclusively for the purpose for which it is intended; incorrect use of the machine shall release the

manufacturer from any liability.

This manual has been prepared to enable the end ---user to carry out only those operations that can be done with the panels
closed. Any operations that require the opening of doors or equipment panels must be carried out only by qualified person­nel.
Each machine is equipped with an electric isolating device which allows the operator to work in conditions of safety. This
device must always be used to eliminate risks during maintenance (electric shocks, scalds, automatic restarting, moving
parts and remote control).
The panel key supplied with the unit must be kept by the person responsible for maintenance.

For identification of the unit (model and serial no.) in case of the necessity for assistance or spare parts, read the identification
labels affixed to the outside and inside of the unit.

IMPORTANT:

Index

1-- Introduction 1...............................................................................

1.1 --- Foreword 1....................................................................................

1.2 --- Responsibility 1................................................................................

1.3 --- Inspection 1...................................................................................

1.4 --- General description 1............................................................................

2 -- Preliminary Operations 1....................................................................

2.1 --- Operating limits 1...............................................................................

2.2 --- Sound pressure levels 1.........................................................................

2.3 --- Transport 2....................................................................................

2.4 --- Foundations 2..................................................................................

2.5 --- Service area 2..................................................................................

3 -- Installation 2................................................................................

3.1 --- Hydraulic connections 2.........................................................................

3.2 --- Connection of the safety valve discharge 3.........................................................

3.3 --- Electrical connections 4..........................................................................

4 -- Start--Up and Operation 4...................................................................

4.1 --- Initial check 4..................................................................................

4.2 --- First start ---up (or after a long stop) 5...............................................................

4.3 --- Starting and stopping 5..........................................................................

4.4 --- Chillers serving special plants 5...................................................................

4.5 --- Freecooling 5..................................................................................

4.6 - -- Microprocessor control 5.........................................................................

5 -- Refrigerant and Oil Charge 5.................................................................

5.1 --- Refrigerant charge 5............................................................................

5.2 --- Oil charge 5...................................................................................

6 -- Safety Devices Settings 6....................................................................

6.1 --- Setting thermostatic expansion valve 6.............................................................

7 -- Maintenance 7..............................................................................

7.1 --- Spare parts 7..................................................................................

7.2 --- Dismantling the unit 7...........................................................................

8 -- Options and Accessories 7...................................................................

8.1 --- Pump set 7....................................................................................

8.2 --- Water chiller with partial heat recovery (20%) 7......................................................

8.3 --- Water chiller with total heat recovery (100%) 8.......................................................

8.4 --- Hydraulic circuit accessories 8....................................................................

8.5 --- Water chiller with inertia tank 8....................................................................

This manual may be subject to modification; for complete and up --- to ---date information the user should
always consult the manual supplied with the machine.

Ta b l e s 9..........................................................................................

Drawings 15......................................................................................

Circuits 23........................................................................................

1 --- Introduction

C

1.1 --- Foreword

This handbook is aimed at enabling both the installer and the op­erator to carry out the correct installation, operation and mainte­nance of the refrigerating machine, without damaging it or caus­ing injuries to the relevant staff.
The handbook is thus an aid for the qualified staff in the arrange­ment of the specific equipment for the correct installation,opera­tion and maintenance in compliance with the local regulations
in force.

The MATRIX S [017 --- 032] water chillers can be identified as fol-
lows:

BH023

Cooling C apacity “kW”

Nominal cooling capacity x 10

Compressor:
H Hermetic Scroll

Version:
B Base
L Low Noise
Q Quiet

Execution:
C Chiller
S Superchiller

1.2 --- Responsibility

Liebert Hiross accepts no present or future responsibility for
damage to persons, things or to the machine itself due to opera­tors’ negligence, failing to comply with the installation, operation
and maintenance instructions of this handbook, failed applica­tion of the safety norms in force for the system and the qualified
staff charged with the operation and maintenance.

1 . 3 --- I n s p e c t i o n

All units are fully assembled and wired in the manufacturing
plant. Before shipment they are charged with the necessary
quantities of refrigerant and oil and then tested at the operating
conditions normally required by the customer. The machine’s
hydraulic circuit is equipped with drain plugs and open vent
valves; the freecooling coils are supplied dry to avoid possible
problems due to frostin the storage period. Immediately inspect
the machine carefully on delivery to check for damage during
transportation or missing components; possible claims must be
made immediately to the carrier and the factory or its representa­tive.

1 . 4 --- G e n e r a l d e s c r i p t i o n

MATRIX S units with air cooled condensers have been designed
and manufactured for producing chilled water.
They are also available in versions with a built -- -in freecooling
module, in versions with heat recovery for simultaneous heating
of thermal circuit water, with a pump assembly installed on the
machine and/or inertial buffer tank inside the machine; the chill­ing units can be equipped with several options indicated in the
price list.
The ”MATRIX S” product line has been designed utilising the
state---of---the---art techniques available nowadays in the indus-

try, and includes all the components necessary for automatic
and efficient operation.

Each unit is completely factory assembled; after evacuation, the
necessary quantity of refrigerant is added to the refrigerant cir­cuit(s) and the unit is tested.
All the units are equipped with oneor two independent refrigerat­ing circuits, each one composed of: an air cooled condenser , a
hermetic Scroll compressors and a braze --- welded plate evapo­rator. The components of the liquid line are the charging valves,
filters dryers, solenoid valve, shut---off valve, moisture indicator
and thermostatic expansion valve.
The hydraulic circuit -- - with max. working pressure 5 bar --- is
made up of carbon steel pipes connected with grooved--- end
(Victaulic) fittings and couplings and include also a flow switch
(optional) and, in the freecooling versions, chilled water coils
and a three ---way valve.

The hermetic scroll compressors are complete with the following
protection/safety devices: oil heater, electronic protection moni­toring the temperature of the motor windings and the direction
of rotation (the latter may be enclosed in the electronics of the
compressororexternal, depending on the model). The ”MATRIX
S” water chillers are controlled by the ”MICROFACE” micropro­cessor,managing all the unit operating conditions.The user can
change and/or modify the operating parameters through the di­splay keyboard installed on the electrical panel.
The electrical control board is equipped with all the safety and
operating devices required for reliable operation. The compres­sor motors are equipped with protection on all three phases and
are started by three --- pole contactors.

2 --- Preliminary Operations

2.1 --- Operating limits

The units can operate within the indicated operating ranges (see
Tab. 7). These limits apply to new machines, subject to correct
installation and maintenance.

S Ambient air minimum temperature: ---25ûC for Superchiller,

+15ûC for Chiller without fan speed control (Operation al­lowed only in summer mode), --- 10ûC for Chiller with contin­uous fan speed control (Either Triac or EC fan);

S Maximum outdoor air temperature is in relation to each mod-

el, as indicated in Tab. 7. In any case outdoor temperatures
aver 45ûC are not admitted; such limits are determined by
electrical and electronic components fitted on units;

S Maximum water flow allowed: depending on the pressure

drop corresponding to the required thermal difference (usu­ally not lower than 3.5ûC --- 4 ûC);

S Minimum allowed water flow: compatible with a sufficient

evaporation temperature, to avoid the intervention of the
safety devices (to be evaluated for a thermal difference not
higher than 8ûC);

S Temperature range of the water exiting the evaporator: 4ûC

--- 1 5 ûC;

S Maximum temperature of the water entering the unit: 20ûC;

higher temperatures are allowed only at the system start--­up and not during normal operation;

S Maximum glycol concentration: 50% (35% with the optional

pump assembly installed on the machine);

S Minimum allowed glycol concentration: depending on the

minimum temperature of the ambient air expected at the
installation site (see Tab. a);

S Maximum pressure of the hydraulic circuit: 5 bar;
S Voltage range for the electric supply: 400 V

phase difference: 3%; tolerance on frequency: 1%.

Storage conditions: from --- 20ûCto45ûCforallMATRIXSmod-
els

Note:
Avoid positioning in areas with strong dominant winds that may
impair the operation and effect the indicated limits.

+

/

10%; max.

---

1

2.2 --- Sound pressure levels

The Tab. 4 shows the noise data for the units in standard config­uration (without pumps), operating continuously and measured
according to the ISO 3744 norm, in free field conditions.
The highest noise levels are detected on the condenser coil side.

Note:
Avoid positioning in areas with possible reverberation of the
sound waves, which can adversely effect the noise levels.

2 . 3 --- T r a n s p o r t

S Handle the unit by lifting it with a crane from above;
S The lifting holes are positioned in the frame’s base (when lift-

ing, use spreader bars to protect the sides, see Fig. 2).

Note:
Place the lifting tubes in the holes in the base indicated by ”LIFT
HERE”. Lock the ends of the tubes with the locking pins and
splits pins as shown in Fig. 2.
The capacity of the lifting gear must be adequate to lift the load
in question. Check the weight of the units, the capacity of the lift­ing gear and ropes and the condition and suitability of the afore­mentioned equipment.

2.4 --- Foundations

S The unit must be placed on a level surface which will support

its weight.

S If necessary, position the unit on suitable anti ---vibration sup-

ports that can be supplied as an option (in rubber or spring --­type). Refer to the manual ”Installation of the spring anti --­vibration supports” for their correct positioning.

S When positioned, level the unit.
Note:

For weight distribution see Fig. 3.
Note:

The weights and their distribution refer to standard units without
options; if the pump assembly, or other options are installed on
the machine, add the weights of the installed accessories to
those of the standard units (see Tab. 8).

2.5 --- Service area

S In order to allow free air flow and maintenance of the unit, a

minimum area must be left free of obstructions around the
unit (see Fig. 1).

S The hot air expelled by the fans must be allowed to rise unim-

peded by obstacles for a minimum height of 2.5 m.

S Avoid recirculation of hot air between the suction and dis-

charge, otherwise the unit performance may be impaired or
the standard operation can be interrupted.

3 --- Installation

3.1 --- Hydraulic connections

3.1.1 -- Hydraulic circuit construction (Fig. a)

The piping must be connected to the chiller. Construct a chilled
water circuit as described below, see Fig. a:

1) Place shut ---off valves within the circuit to allow servicing;

2) Install a pump system suitable for the flow rate required at
a pressure head equal to the sum of all the pressure drops
(see project data).
Matrix S chillers can be equipped, upon request, with
pumps having performance as indicated in Tab. 8;

3) Install manometers at the chiller inlet/outlet;

4) Install thermometers at the chiller inlet/outlet;

5) Connect the pipes to the chiller by flexible joints to avoid
transmitting vibrations and to balance the thermal expan­sion; proceed in the same way even if the pump set is out­side the chiller;

6) It is useful to include a water pressure switch to give an early
warning of low water pressure;

7) Place a mesh filter at the inlets of the pump and water chiller
(Can be supplied as an optional accessory --- Not fitted);

8) Install, at the highest points in the circuit, apparatus which
allows the bleeding of air and possibly the filling of glycol;

9) Place a drain valve at the lowest point in the circuit and im­mediately at the outlet of the water chiller;

10) Install a water filling set including the following:
a) filling water meter;
b) manometer;
c) non---return valve;
d) air separator;
e) removable supply tube, which must be disconnected

after each charge/top---up;

11) For maximum protection ensure that all tubing exposed to
low outdoor temperatures is fitted with anti ---freeze heaters
and insulated using closed cell synthetic rubber (elasto­mer);

12) The circuit must include an expansion vessel (with safety
valve) of suitable capacity;

13) Connect the lines avoiding stresses on the machine inner
parts.

Note:
If the water chiller is complete with an expansion vessel (sup­plied as an option), check if the capacity is enough, and install
a second vessel in the circuit, if required (see par. 8.4).
Follow the indications in Fig. c for the correct sizing.

Note:
The whole circuit must contain a water volume suitable for the
capacity of the installed chiller. Check if the inertial capacity giv­en by the sum of the hydraulic volume inside the machine (in­cluding the volume of the optional interna tank, if fitted) and the
system volume is sufficient, or possibly install a tank in the circuit.
Follow the indications in Fig. b for the correct sizing.

Note:
The hydraulic circuit must ensure a constant water supply to the
evaporator in every operating condition. Otherwise, the com­pressors may be damaged by repeated returns of liquid refriger­ant on their suction.

Note:
The water flow switch is a compulsory safety component that
must be installed and correctly wired to the Matrix S chillers,
otherwise the guarantee will be invalidated.
It is installed, as standard, on units with the optional on --- board
pump set, and is available as a option for units without pumps
on board: in the latter case the flow switch, if not installed on the
machine, can be installed on the hydraulic circuit by the installer,
butitiscompulsorythatitiswiredtotheelectricpanelterminal
board, as indicated on the wiring diagram.

3.1.2 -- Addition of water and ethylene glycol

Very important:
Add water and ethylene glycol to the circuit with a % depending

on the minimum temperature of the outside air expected at the
installation site. Do not exceed the nominal operating pressure
of the circuit’s components.

Notes:
S To avoid stratification run the circulation pump for at least 30

minutes after adding any glycol.

S After adding water to the hydraulic circuit always discon-

nect the water supply coming from the sanitary supply;

this avoids the danger of glycol entering the sanitary water
system.

S After any topping --- up of the water check the concentration

and add glycol if necessary.

3.1.3 -- Water--glycol mixture

Water---glycol mixtures are used as the thermal carrier fluid in
very cold climates or with temperatures below zero degrees cen­tigrade. Determine the ethylene glycol % which must be added
to the water, with the assistance of Tab. a.

2

Tab.a--Ethyleneglycoltobeaddedtowater

(% in weight of total mixture)

Ethylene glycol

(% in weight)

Freezing tempera-

(*)

ture, ûC

Mixture density at

(*)

,kg/l

20ûC

(*) Values are for Shell antifreeze 402. For different brands, check

manufacturer’s data.

For the chiller internal water volume refer to Tab. 1. If the optional
buffer tank is installed on the machine, add the tank hydraulic
volume.

0 10 20 30 40 50

0 --- 4 . 4 ---9 . 9 --- 1 6 . 6 --- 2 5 . 2 --- 3 7 . 2

--- 1.017 1.033 1.048 1.064 1.080

ALWAYS CHARGE THE HYDRAULIC CIRCUIT WITH THE RE­QUIRED GLYCOL % NECESSARY FOR THE MINIMUM AMBI­ENT TEMPERATURE AT THE INSTALLATION SITE. FAILING
TO COMPLY WITH THIS INSTRUCTION SHALL INVALIDATE
THE UNIT WARRANTY.

3 . 2 --- C o n n e c t i o n o f t h e s a f e t y v a l v e

discharge

Safety valves are installed on the high pressure side of the refrig­eration circuit: the discharge of these valves must be conveyed
outside through a suitable pipe, having a diameter of at least that
of the valve outlet, without burdening the valve body.Convey the
discharge to areas where the jet cannot harm people and the
surrounding environment.

Fig. a --Ideal chilled water circuit

disconnect af-

ter charge

10e

10d10c10b10a

12

Fig. b --Inertia tank sizing

The total optimum hydraulic volume of the system where the Matrix S chiller is installed can be calculated by the
following formula:

43 x Rt

V =

where:

--- V=minimum required total water volume expressed in litres

--- Rt=refrigeration capacity expressed in kW

--- Xd=differential band set on the control and expressed in degrees centigrade

Xd

flow

9

Vpt

Ta n k

1 1327436

5

T T

CHILLER

5 5 9

USER

11

11

4

8

Please note that the sum of the hydraulic volume of the Matrix S chiller (Vm) plus the volume of the hydraulic circuit
connected to it (Vpc) must be greater than, or equal to the minimum required total water volume (V). If this condi­tion is not satisfied, it is necessary to install an inertia tank (Vpt, as indicated in the Fig. a) with a volume at least
equal to the following value: Vpt=V ---Vm---Vpc

3

Fig. c --Sizing of the expansion vessel

The total volume of the expansion vessel is calculated with the following formula:

C x e

V =

1 --

Pi
Pf

where:

-- - C=quantity of water inside the system expressed in litres

-- - e=water expansion coefficient, with water at 10ûC as a reference

-- - Pi=absolute pressure of initial charging, equivalent to the vessel pre --- charge pressure (typical value

2.5 bara)

-- - Pf=absolute final tolerated pressure, lower than the operating pressure of the safety valve calibration
pressure (typical value 4.0 bara).

Use the values of the water expansion coefficient indicated in the table below:

H2OT[°C] Density [kg/m3] Expansion coefficient “e”

10 999.6 --- --- ---

20 997.9 0.0017

30 995.6 0.0040

40 992.2 0.0075

50 988.1 0.0116

3.3 --- Electrical connections

1) Before proceeding with the electrical connections, ensure
that:

S all electrical components are undamaged;
S allterminalscrewsaretight;
S the supply voltage and frequency are in accordance with

the rating (with tolerance in accordance with IEC 8--- 6
norms, March 1990)

S the allowed phase to phase variability is 3% maximum

(see Fig. d). Variability in excess of 3% invalidates the
guarantee.

2) Supply cable connections (see Tab. 6):

S Connect the cable to the supply terminals.
S Use appropriately sized 3--- pole cable. An earth wire

must also be connected.

S After having opened the passagein the framework (pre -- -

punched knock ---outs) for the supply line entry, restore
the original degree of protection using suitable accesso­ries for the wiring and junction boxes.

Fig. d --Example of calculating phase

1) The 400 V supply has

2) The average voltage is:

3) The maximum deviation from the average is:

4) Thephasetophasevariabilityis:

Note:
The power supply should never be disconnected, except when
performing maintenance.

to phase variability

the following variability:

RS = 388 V
ST = 401 V
RT = 402 V

388 + 401 + 402

3

402 --- 397 = 5 V

5

x 100 = 1.26 (acceptable)

397

RS T

= 397

Operate (open) the main switch before carrying out any mainte­nance work on electrical components.

Note:
It is forbidden to work on the electrical components without
using insulating platforms, and in the presence of water or fog
or mist.

Note:
The supply to the external pump assembly mustbe made before
starting the chiller and must be kept on as long as the chiller is
in use. Incorrect operation will cause the unit to lock--- out be­cause of the internal protections (flow switch intervention).

Note:
The compressors are equipped with an electronic protectionde­vice blocking their start if the phase sequence is not correct, or
stopping their operation if a thermal relay intervenes. This device
is essential for the integrity of the mechanical and electrical com­ponents of the compressors. Reset the standard functions by
isolating this device and removing the causes of the lock---out.

Note:
The chillers are equipped with their own microprocessor control
adjustment. The use of the remote ON --- OFF input (located in
the electric panel terminal board) as a system temperature con­trol element is forbidden.

4 --- S t a r t --- U p a n d O p e r a t i o n

4.1 --- Initial check

1) Check all water connections.

2) Open the shut---off valve on the liquid line.

3) Ensure that the intake pressure is higher than 4.0 bar; if this
is not the case, prolong pre --- heating of the compressor (if
possible) and check that the refrigerant shut --- off valve is
properly sealed, see Fig. 9.

4) Open all isolating valves and/or water ball valves.

5) In case of climates with temperatures below zero degrees C,
make sure the chilled water circuit is filled with the correct
concentration of water/glycol.

6) Bleed all air out of the chilled water circuit.

7) Verify the water flow rate and its direction.

8) Ensure that the thermal load is sufficient for start---up.

Caution:
The ambient air temperature probe must be positioned in the
shade and protected against the weather.

4

4 . 2 --- F i r s t s t a r t --- u p

(or after a long stop)

Operate as follows:

1) At least 8 hours before the start ---up, power the crank-

case heaters by setting the main isolator switch ON.
Make sure the auxiliary circuit has been powered and
check the operation (a fault due to an incorrect proce­dure will invalidate the compressor guarantee).

2) Open the valves of the refrigeration circuit that had been
closed before the initial check.

3) Check the machinery supplying the thermal load connected
with the unit and start the system pump(s).

4) MAKE SURE THE COMPRESSOR OIL HAS BEEN HEATED
FOR AT LEAST 8 HOURS; start the unit only then.

5) Make sure the fans rotate in the correct direction (anticlock­wise): check the electrical connections, if necessary .

6) Make sure the pumps rotate in the correct direction.

7) During the unit start ---up an inlet water temperature

higher than 20ûC is allowed. Under standard operating
conditions check that the limits indicated in paragraph

2.1 are not exceeded.

8) Check the correct operation of the control and safety de­vices.

9) Check the outlet temperature of the chilled water (check if
the set--- point set on the controller is reached).

10) Check the oil level in both compressors.

11) With the compressors at full load, check there are no
bubbles visible in the frefrigerant sight glass. If there are any,
charge the unit according to par. 5.

4.3 --- Starting and stopping

ALWAYS ENSURE THAT THE COMPRESSOR OIL HAS BEEN
PREHEATED.
FOR BRIEF STOPPAGES MAINTAIN THE SUPPLY TO THE
CRANKCASE HEATER.

S Start the unit setting the Microprocessor switch ON.
S Stop the unit setting the Microprocessor switch OFF.
S In case of long stops, turn the machine off using the Micro-

processor switch OFF.
In this case the compressor crankcase heaters remain pow­ered.

S For seasonal shutdown of the unit operate the main switch

locatedon the main electrical power supply. This will discon­nect the compressor crankcase heaters.

4.4 --- Chillers serving special plants

The units are capable of cooling a water ---glycol mixture to tem­peratures close to 0ûC without the need for significant modifica­tions. In the case of modification, the set values of the safety and
control components must also be changed. This can be carried
out in the factory (at the time of testing) or at the time of installa­tion, only by qualified and authorised personnel.

4 . 5 --- F r e e c o o l i n g

The “freecooling” is a system of pre ---cooling and/or cooling the
water/glycol mixture using ambient air when the latter is at a tem­perature below the return mixture temperature. If the outside
temperature is sufficiently low to dissipate the entire heat load,
the refrigeration compressors automatically switch off, and the
mixture’s temperature is controlled by the fan speed adjust­ment.
If the mixture temperature is too high for freecooling, the com­pressors will operate as long as necessary to ensure the correct
water/glycol mixture temperature.

4.6 --- Microprocessor control

Consult the ”Microface and Hiromatic” Service Manual.

5 --- R e f r i g e r a n t a n d O i l C h a r g e

All work on pipes or components of the refrigerating circuit un­der pressure must be exclusively carried out by qualified staff,
competent in such works.

5 . 1 --- R e f r i g e r a n t c h a r g e

WHILST REPAIRING THE REFRIGERATING CIRCUIT RE­COVER ALL THE REFRIGERANT IN A CONTAINER: DO NOT
ALLOW IT TO ESCAPE. NEVER U SE THE COMPRESSOR
FOR THE SYSTEM VACUUM (THIS INVALIDATES THE
WARRANTY).

S The unit is delivered charged according to the Tab. 5.
Warning for the refrigerant charge:

S Ensure there are no refrigerant leaks.
S Check the refrigerant type in the refrigeration circuit: a unit

originally charged by the manufacturer with R407C cannot
be charged with R22 and vice versa; possibly apply to the
Technical Support Department.

S Charge with the compressor in operation, connecting the

cylinder with the charge connector after the thermostatic ex­pansion valve.
Flush the connection pipe between the cylinder and the
charging point; tighten the seal joint and then start charging
the unit. It is imperative that the cylinder is weighed both be­fore and after the operation.

S For the units with R407C the refrigerant charge must be

made exclusively with liquid refrigerant.

S Charge the unit until the bubbles in the sight glass have dis-

appeared and the working conditions of the entire refrigera­tion circuit have returned to normal (sub ---cooling and su­perheating within the limits indicated below).

S Measure the superheating as follows:

1) Detect the temperature on the suction line, close to the
bulb of the thermostatic expansion valve, using a contact
thermometer.

2) Connect a pressure gauge (by max. a 30 --- cm pipe) with
the Schraeder connection and read the corresponding
saturated evaporating temperature.

3) The superheating is the difference between the two
readings.

4) For the units with R407C refer to the pressure gauge
scale indicated with the initials D.P. (Dew Point)

S Verify that the superheating is 5ûC --- 8 ûC.
S Measure the sub---cooling as follows:

1) Detect the temperature on the liquid line using a contact
thermometer.

2) Connect a pressure gauge (by max. a 30 --- cm pipe) with
the Schraeder connection on the liquid line and read the
corresponding saturated condensing temperature.

3) The sub --- cooling is the difference between the two read­ings.

4) For the units with R407C refer to the pressure gauge
scale indicated with the initials B.P. (Bubble Point)

S Verify that at the condenser outlet, sub--- cooling is 3ûC---

5ûC.

IT IS IMPORTANT TO CARRY OUT CHARGING CORRECTLY.
An excess of refrigerant causes an increase in sub ---coolingand
consequent operating difficulties in the hot season; a shortage
of charge generates an increase in superheating and possible
compressor stoppages. Whenever work is carried out on the
unit, ensure afterwards that the working conditions are correct,
checking sub---cooling and superheating.

5 . 2 --- O i l c h a r g e

Contact the TechnicalSupport Department for the specifications
of the oil to be used for topping up; the oil changes according to
thetypeofusedrefrigerant.

NEVER MIX DIFFERENT OILS TOGETHER. CLEAN THE PIP­ING COMPLETELY BEFORE CHANGING THE TYPE OF OIL
USED.

5

TOP ---UPS OF UP TO 20---30% OF THE TOTAL AMOUNT OF
OIL CONTAINED IN THE COMPRESSOR CRANKCASE ARE
PERMITTED; FOR LARGER PERCENTAGES CONTACT THE
TECHNICAL SUPPORT DEPARTMENT.

5.2.1 -- Procedure for oil topping--up

If there has been any loss of oil then this must be topped up as
follows:

1) T ake a clean, dry, transparent container (with volume cal­ibrations) and fill it with at least twice the amount of oil re­quired.

2) Isolate the compressor by closing the cock on the liquid line.

3) Connect to the fittings on the compressor body (Schraeder
valves) and empty it of refrigerant until atmospheric pres­sure (1 bar) is reached.

4) Using a pipe, connect the oil containerto the oil service fitting
on the lower part of the compressor.

5) Open the oil service cock, lifting the container, so that the oil
flows by gravity.

6) Charge the required quantity of oil (make sure the tube al­ways remains below the oil level in the container).

7) Stop the oil flow by closing the oil service fitting, open the
shut---off cock on the refrigerating circuit and restore the
drained refrigerant charge.

6 --- Safety Devices Settings

The water chiller has already been tested and set up by the manufacturer. The following setting values are suggested in the field.

COMPONENT SETTING NOTES

diff.set

Operation with R407C/R22

Low pressure switch (LP)

(standard factory setting):

START : 3.6 bar
DIFF. : 0.8 bar
STOP : 2.8 bar

0.2

5

1.5

0.5

bar

bar

Operation with R407C/R22
(standard factory setting):

High pressure switch (HP)

STOP : 26 bar
START : 20 bar
DIFF. : 6 bar (fixed)

The settings for the safety valves installed on the machine are indicated below:

MODELS SETTINGS SAFETY VALVE

CBH/CLH/CQH 017 --- 020 ---023 ---025 ---028

SBH/SLH 017---020---023 ---025 ---028

SQH 017 ---020 ---023 ---025

6.1 --- Setting the rmostatic expansion
valve

THIS OPERATION MUST BE PERFORMED BY AN EXPERI­ENCED REFRIGERATION TECHNICIAN.
Before beginning this adjustment be sure that the refrigerant

charge is correct, checking the the sub --- cooling (3ûC --- 5ûC, as

specified in par. 5.1).
The valve has already been factory --- set and should be reset
when the superheating is not between 5ûC --- 8 ûC, as follows:

1) Important:

Ensure that the instructions in par.5.1 have been carried out.

2) Allow the compressor to operate for 15 mins.

3) Measure the superheating as follows:

a) Connect a manometer to the Schraeder connection lo-

29 bar high pressure side

a) Remove the protective cover;
b) Turn the adjustment screw to return to the optimum val-

ues, tightening it in a clockwise direction to increase the
superheating, or slackening it to reduce the superheat-

ing.
c) Wait about 10 minutes;
d) Measure the superheating and repeat the operation if

necessary.

N.B:
If the superheating is too low, there is a risk of poor lubrication

and consequent breakage of the compressor as a result of pres­sure shock.
If the superheating is too high the output of the system is limited
and the compressor overheats.

cated on the evaporator outlet tube, and read the mano­metric temperature on the scale for the refrigerant used
(for the units with R407C refer to the pressure gauge
scale indicated with the initials D.P. = Dew Point).

b) Using a contact thermometer, measure the temperature

on the tube coming out of the evaporator, next to the
socket used for the manometer.

c) The superheating is the difference between the two

readings (b ---a).

4) The superheating must be 5ûC --- 8 ûC; if not, set the expan-

sion valve as follows:

reset

6

7 --- Maintenance

The Maintenance Programme below must be carried out by a
qualified technician, preferably working under a maintenance
contract.
Before any intervention on the unit or accessing the inner com­ponents (removing the outer panels), always ensure the ma­chine is switched off. If the front upper panels are removed (coil
compartment) wait for the fan(s) to come to a complete stop be­fore accessing the compartment; if the front lower panels are re­moved, pay special attention when working near the com­pressor upper part and the discharge line: they are very hot;
possibly wait for them to cool. Be very careful when operating
closeto the finned coils, as the fins are very sharp. Do not remove
the fan protection grille before electrically isolating the whole
machine. Do not insert foreign matter through the fan protection
grille. After the maintenance interventions, always close the unit
with the suitable panels, fastened by the tightening system.

Maintenance programme -- Monthly check

S Check that the fan motor rotates freely without any abnormal noise, and ensure that the

FANS

CONDENSER AND AIR FILTER

CONTROL S Check that the control equipment, LEDs and display are operating correctly.

ELECTRICAL CIRCUIT

REFRIGERATION CIRCUIT

CHILLED WATER CIRCUIT

bearings are not running hot.

S Also check the current absorption.

S Check the conditions of the filters (if they are supplied); if necessary clean them (including

the electrical panel ventilation filter).

S Check the condenser coils and clean if necessary with compressed air or soft brushes.

S Check the electrical supply on all phases.
S Ensure that all electrical connections are tight.

S Check the condensing and the evaporating pressures (to be done by a refrigeration techni-

cian).

S Check the compressor’s current absorption, the delivery temperature and possible unusual

noises.

S Check the refrigerant charge by means of the sight glass.
S Check that the safety devices operate correctly.

S Check the correct operation of the thermostatic valve (superheating between 5ûC --- 8ûC).
S Check that the oil level indicated by the compressor sight glass is higher than the min. value.

S Ensure that there are no water leaks.
S Bleed any air out of the hydraulic circuit using the bleed valves.
S Verify that the water flow rate is correct.
S Check the inlet --- outlet liquid temperature and pressure.
S Check the correct operation of the three--- way valve (Versions with free--- cooling only).
S Check if the system is charged with the specified glycol percentage and that no ice has

formed in the hydraulic circuit.

S Check the evaporator cleanliness.

7.1 --- Spare parts

The use of original spare parts is recommended.
When placing an order refer to the ”Component List” enclosed
with the machine and quote the unit model no. and serial no.

7.2 --- Dismantling the unit

The machine has been designed and built to ensure continuous
operation.
The working life of some of the main components, such as the
fans and the compressors, depends on the maintenance that
they receive.
If the unit has to be dismantled, the job must be done by skilled
refrigeration technicians.
The refrigerant and the lubricating oil in the circuit must be dis­posedofinconformitywiththelawsinforceinyourcountry.

8 --- O p t i o n s a n d A c c e s s o r i e s

8 . 1 --- P u m p s e t

The centrifugal pump units are direct driven, with cl ose--­coupled motors and a single shaft; the induction motor has 2
poleswithIP55protectionandclassFinsulation.

Pump casings and impellers are in cast iron EN -- -GJL 200, shafts
are in stainless steel, the shaft seal is a unbalanced, mechanical
shaft seal with dimensions according to DIN 24 960 and assem­bly length according to EN 12 756, brass neck ring permits ideal
conditions for the use of water mixtures containing ethylene gly­col. The pump housing, the motor stool and the motor stator
housing are electrocoated.

The pump units have been chosen and sized to operate within
specific limits, namely:

S Water / ethylene glycol mixtures up to 65% / 35% by weight;
S Temperatures of the standard pumped fluid not lower than

4°C.

The motor stool forms connection between the pump housing
and the motor, and is equipped with a manual air vent screw for
venting of the pump housing and the shaft seal chamber. It is
very important to carry out this operation as the circulation of liq-

uid through the duct of the air vent screw ensures lubrication and
cooling of the shaft seal.

Between the outlets of the two chambers and the discharge
flange, twin --- head pumps have a non --- return flap valve in
EPDM rubber. The flap is opened by the flow of the pumped liq­uid and cuts off the port of the idle pump chamber.

In the electrical panel there are automatic circuit breakers for
each pump; the microprocessor control manages the operating
rotation between the two pumps and start - --up of the stand--- by
pump if the primary pump fails.

For the technical features of the pumps and the hydraulic sche­matic see Tab. 8, Fig. 10 and Fig. 11.

8.2 --- Water chiller with partial heat

recovery (20%)

This option enables the recovery of up to 20% of the heat normal­ly rejected by the condensers (see Tab. 2). The system does not
require any adjustment and is made up of plate heat exchangers
installed on each circuit before the condenser. The exchangers
are protected by a suitable anti---frost heater that operates when

7