McQuay ALZ "B" Manual

Air cooled water chillers
Air cooled motocondensing unit
ALZ “B” 011.1 ÷ 038.2
ALP “B” 011.1 ÷ 038.2
Cooling capacity from 40 to 145 kW
50Hz –Refrigerant: HFC 407C
Scroll Compressors
Installation and maintenance manual
304 C –02/06 D
Date: June 2002
Supersedes: 304 C-02/01 C

304 C –02/06 D –pag. 2/16
Introduction
Purpose of the manual
The manual allows the installer and the operator to perform correctly all the operations referred to the installation
and maintenance of the chiller without provoking any damages to the unit or to the qualified personnel.
Therefore the manual is a great help for the qualified personnel that have to arrange the equipment to provide the
correct installation in accordance with local codes and regulation.
Inspection
When the equipment is received, all items on the bill of lading should be carefully checked to insure a complete
shipment. All units should be carefully checked and all shipping damage should be reported to the carrier. The unit
serial plate should be checked before unloading the unit to be sure that it agrees with the power supply available.
Physical damage to unit after acceptance is not McQuay responsability.
Responsabilities
McQuay Italia declines all present and future responsabilities referred to injuries to people and damage to things
and unit, coming from operators negligence, the unrespected installation/maintenance data carrier in this manual,
the lacking of the current regulations respect referred to the safety of the equipment and the qualified personnel.
Servicing and maintenance
Servicing and maintenance of these unit must carried out by experienced personnel with specifing training in
refrigeration. Repeated check the safety devices and continous cycling of control components must be analyzed
and corrected before being reset.
The simple design of the refrigeration circuit totally eliminates potential problems during normall unit operation. No
maintenance work is needed on the refrigeration circuit as long as the unit is operating normally.
Characteristics
General description
McQuay International introduces their newest air cooled water chiller ALZ/ALP equipped with scroll compressors
and electronic control system. McQuay have once again succeded in developing a high quality product with
extraordinary performance which is able to satisfy HVAC applications.
McQuay units are completely factory assembled, piped, wired and charged with refrigerant and shipped ready for
the installation.
Each unit consists of scroll compressors, condenser coils with independent subcooler circuits, multiple propeller
type direct drive condenser fans with independent fan motors, heavy-gauge weatherproof casing and weatherproof
electrical control centre containing all necessary and operating controls and motor starting equipment.
ALZ/ALP units are high thermodynamic engineering products, studied with high accuracy in balancing
compressors, condensers and evaporators in order to offer high performances and wide safety margins. The
choose of the materials and the equipments adopted for the products has been made without any compromises,
taking care of quality and long life purposes. The products meet ISO 9001 requirements, an assurance, beyond
any doubts, of the high producing standards followed by McQuay.

304 C –02/06 D –pag. 3/16
Electrical data ALZ/ALP “B”
Unit size 011.1
013.1
017.1
020.1
022.2
025.2
029.2
033.2
036.2
038.2
Standard voltage (1) 400 V -3f –50 Hz + NEUTRAL
Nominal unit current (2) A
32,3 37,8 45,4 54,8 64,1 75,9 83,9 93,5 99,4 109,8
Max compressor current (3) A
29,3 35,4 44,4 54,6 61,0 74,4 83,8 95,2 98,0 109,6
Fans current A
5,4 5,4 5,4 5,4 8,1 8,1 8,1 8,1 10,8 10,8
Max unit current (3) A
34,7 40,8 49,8 60,0 69,1 82,5 91,9 103,3
108,8
120,4
Max unit inrush current (4) A
151,6
154,3 203,1 207,8 186,2
195,0
246,0 253,2
260,4
268,2
Max unit current for wires sizing (5) A
45,4 63,4 65,4 75,4 88,1 124,1
126,1 128,1
140,8
150,8
Notes: (1) Allowed voltage tolerance ± 10%. Voltage unbalance between phases must be within ± 3%.
(2) Nominal current are based on: 12/7 °C entering/leaving evaporator water temperature and 35°C ambient temp.
(3) Maximum current are based on: 14/9 °C entering/leaving evaporator water temperature and 40°C ambient temp.
(4) Inrush current of biggest compressor + nominal absorbed current of the other compressors.
(5) Compressor FLA + fans current.
Operating limits
Entering evaporator
water temperature Leaving evap. water temp.(without glycol) Evaporator water ∆∆t Ambient temperature ALZ Min. (°C) Max (°C) Min. (°C) Max (°C) Min. (°C) Max (°C) Min.(°C)(*) Max (°C)
011.1 820 415 4815 42
013.1 820 415 4815 42
017.1 820 415 4814 42
020.1 820 415 4812 40
022.2 820 415 4815 42
025.2 820 415 4813 40
029.2 815 410 4812 40
033.2 815 410 4810 40
036.2 820 415 4815 42
038.2 820 415 4815 40
(*) for ambient temperature down to –18°C low ambient kit is required (fan speed control)
Altitude correction factor
Elevation above sea level (m) 0300 600 900 1200 1500 1800
Barometric pressure (mbar) 1013 977 942 908 875 843 812
Cooling capacity correction factor 1,000 0,991 0,981 0,972 0,962 0,953 0,943
Ethylene glycol and low ambient temperature correction factors
Air ambient temperature °C -3-8-15 -23 -35
% of ethylene glycol correction factor 10 20 30 40 50
Cooling capacity correction factor 0,986 0,980 0,973 0,966 0,960
Flow rate correction factor 1,023 1,054 1,092 1,140 1,200
Water pressure drops correction factor 1,061 1,114 1,190 1,244 1,310
Low temperature operation performance factors
Ethylene glycol/water leaving temperature °C 20-2-6-8
Cooling capacity correction factor 0,842 0,783 0,725 0,6150,562
Power input compressors correction factor 0,950 0,934 0,918 0,870 0,845
Min % of ethylene glycol 10 20 20 30 30
Max air ambient temperature °C 40 40 38 34 32
Fouling factor
Fouling factor
m2 °C / kW Cooling capacity correction factor
0,044 1,000
0,132 0,986
0,308 0,939

304 C –02/06 D –pag. 4/16
Physical data ALZ “B” HFC 407C units
Unit size 011.1 013.1 017.1 020.1 022.2
Cooling capacity (1) kW 42,7 49,4 60,6 71,8 84,3
Power input (1) kW 13,9 16,9 22,0 27,4 29,4
Cooling cap. heat recovery cond.(2) kW 43,5 52,762,5 79,7 87,5
Heating capacity (2) kW 56,2 67,0 82,2 103,7 113,5
Power input heat recovery cond. (2) kW 14,5 16,3 22,2 27,2 29,6
Desuperheaters heating capacity (3) kW 10,4 12,2 14,8 17,7 21,0
Desuperheaters pressure drops (3) kPa 14 18 15 20 18
Scroll compressors
No. of compressors / No of circuits 1 Tandem/1
1 Tandem/1
1 Tandem/1
1 Tandem/1
2 Tandem/2
Oil charge l6,5 6,5 10,4 13,2 6,5+6,5
No. of reduction steps 22222
Refrigerant charge kg 5,5 6,0 7,0 8,5 11,0
Plate heat exchange
Water volume l2,6 2,9 3,6 4,4 5,2
Max. water pressure bar 30 30 30 30 30
Condenser fans
No. of fans / Diameter mm 2 / 630 2 / 630 2 / 630 2 / 630 3 / 630
Motor power / rotation regime kW / rpm
0,6 / 880 0,6 / 880 0,6 / 880 0,6 / 880 0,6 / 880
Dimensions and weights
Unit length mm 2780 2780 2780 2780 3530
Unit width mm 1200 1200 1200 1200 1200
Unit height mm 1400 1400 1400 1400 1400
Standard unit shipping weight kg 453 576 609 662 733
Unit with two pumps and tank weight kg 503 666 699 762 833
Unit size025.2 029.2 033.2 036.2 038.2
Cooling capacity (1) kW 95,3 107,5 117,2 133,5 144,5
Power input (1) kW 36,2 41,3 47,7 49,6 54,8
Cooling cap. heat recovery cond.(2) kW 100,4 116,1 123,9 143,9 151,3
Heating capacity (2) kW 132,4 152,4 166,3 189,6 200,9
Power input heat recovery cond. (2) kW 35,8 41,5 47,9 51,2 55,4
Desuperheaters heating capacity (3) kW 23,4 26,6 28,4 32,7 35,7
Desuperheaters pressure drops (3) kPa 20 19 24 24 25
Scroll compressors
No. of compressors / No of circuits 2 Tandem/2
2 Tandem/2
2 Tandem/2
2 Tandem/2
2 Tandem/2
Oil charge l6,5+6,5 6,5+10,4 10,4+10,4 10,4+13,2 13,2+13,2
No. of reduction steps 22222
Refrigerant charge kg 13,0 16,0 18,0 23,0 23,0
Plate heat exchange
Water volume l5,8 6,8 7,6 9,7 9,7
Max. water pressure bar 30 30 30 30 30
Condenser fans
No. of fans / Diameter mm 3 / 630 3 / 630 3 / 630 4 / 630 4 / 630
Motor power / rotation regime kW / rpm
0,6 / 880 0,6 / 880 0,6 / 880 0,6 / 880 0,6 / 880
Dimensions and weights
Unit length mm 3530 3530 3530 4280 4280
Unit width mm 1200 1200 1200 1200 1200
Unit height mm 1400 1400 1400 1400 1400
Standard unit shipping weight kg 860 892 940 1115 1140
Unit with two pumps and tank weight kg 960 992 1040 1215 1240
Notes: (1) Nominal cooling capacity and power input are based on: 12/7 °C entering/leaving evaporator water temperature;
35°C ambient temperature.
(2) Nominal cooling capacity, power input and heating capacity are based on: 12/7 °C entering/leaving evaporator
water temperature; 45°C leaving HR water temperature.
(3) Desuperheaters heating capacity and pressure drops are based on: 12/7°C entering/leaving evaporator water
temperature; 40/45°C entering/leaving desuperheater water temperature; 35°C ambient temperature.

304 C –02/06 D –pag. 5/16
Safety measures
The unit must be suitably clamped to ground.
It is necessary to follow these cautions and warnings:
-The unit must be lifted only by using the proper tools able to support the weight of the unit.
-No admittance to unauthorized or unqualified personnel.
-No operation on electrical components is allowed without having switched off electricity supply.
-No operation on electrical components is allowed without using insulated platforms; no water or moisture should
be present.
-All the operation on refrigerant circuit and pressurised components are to be performed by qualified personnel
only.
-Compressor substitution or oil addition in this one must be performed by qualified personnel only.
-Sharp edges and coil surface are a potential injury hazard. Avoid contact with them.
-Disconnect all power to the unit while servicing condenser fan motors. Failure to do so may cause body injury.
-Avoid unrelated bodies into the water piping during the unit connection to the water system.
-It is necessary a mechanical filter for the piping connected to the exchangers entry.
Installation
Before any operation please check the instruction for use.
Warning
Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and
regulations, and who are experienced with this type of equipment. Must be avoided the unit installation in places
that could be considered dangerous for all the maintenance operations.
Transport
It is necessary to be sure of the stability of the unit during transportation. Therefore the unit is supplied with a
transversal wooden beam placed on the unit base that must to be removed only after the final destination. In case
the unit has to be moved again, a similar solution is necessary.
Handling and lifting
Care should be taken to avoid rough handling or shock due to the unit drop. Do not push or pull the unit from
anything else than the base. When it is necessary to lift the unit suitable buttonholes are provided in unit base to
arrange spreader bars and cables to prevent damage to the condenser coils or cabinet.
Location
The ALZ units are produced for outside installation on roofs, floors or below ground level on condition that the area
is free from obstacles for the passage of the condensation air. The unit should be positioned on solid foundations
and perfectly level; in the case of installation on roofs or floors, it may be advisable to arrange the use of suitable
weight distribution beams. When the units are installed on the ground, a concrete base at least 250 mm wider and
longer than the unit’s footprint should be laid. Furthermore, this base should be sufficiently robust to withstand the
unit weight mentioned in the technical data table. When the units are positioned in areas which are easily
accessible by persons or animals, it is advisable to fit guards (option) to protect the condenser coil and the
compressors.
Besides to obtain the best performance the location area it is necessary to follow the next precaution and advise:
•Avoid air flow recirculation.
•Take care that obstacle do not obstruct air flow.
•Breezy ambient is required to ensure the right air suction and delivery.
•To reduce noise and vibration a stiff floor is required.
•To avoid that condenser coils get dirty avoid dusty ambient.
•Chiller water must be quite clean and deprived of oil trace and rust particles. It is necessary a water filter on the
entering water pipes.

304 C –02/06 D –pag. 6/16
Space requirements
The ALZ units are air-cooled, hence it is important to observe the minimum distances which guarantee the best
ventilation of the condenser coils. Limitations of space reducing the air flow could cause significant reductions in
cooling capacity, and increase in electricity consumption. The fans do not allow the use of ducts which have high
flow resistance, hence is should be ensured that the output air cannot recycle itself inside the condenser coils. The
units should be positioned such that there is sufficient distance between the coils and any obstacles to improve
ventilation and also to facilitate inspection (fig. 1).
When two or more units are positioned side by side it is recommended that the condenser coils are at least 2500
mm distance from one another (fig. 2). Smaller distances could cause the recirculation of hot air. If the units are
positioned in places surrounded by walls or obstacles of the same height as the units, the units should be at least
2000 mm from said obstacles (fig. 3). In the event the obstacles are higher than the units, the units should be at
least 2500 mm from the obstacle (fig. 4). For other installation solutions, consult McQuay technicians.
Acoustic protection
The low noise levels of the ALZ units means that they meet most of the most restrictive regulations. When the
noise level must meet special requirements it will be necessary to pay the maximum attention to ensure the perfect
insulation of the unit from the support base by applying appropriate vibration-dampening devices, applying
vibration-dampening mounts on the water pipes and on the electrical connections (by the customer).
Water piping
§Shut-off valves should be provided at the unit so that normal servicing can be accomplished without draining
the system.
§It is recommended that temperature and pressure indicators are installed at the heat exchangers inlet and
outlet to aid the normal checking and servicing.
§It is recommended the installation of a wire mesh stainer at the pump suction to protect the pump and the
exchangers from foreign matter.
§Before insulating the piping and filling the system, a preliminary leak check should be made.
§Vibration eliminators are recommended in all lines connected to the unit.
§Automatic flow control devices, although not furnished with the chiller as they are plant components, must be
necessary be installed.
Evaporator and condenser water connections size are 2” for all ALZ units.

304 C –02/06 D –pag. 7/16
Freeze protection
If the unit is installed in an area where the ambient temperature can fall below 0°C, the heat exchanger, the piping
and the inertial water tank can be damage by frost, despite the electric heater (standard supplied on the heat
excharger and the tank). In this case is recommended to add ethylene glycol with an adeguate concentration (see
table on page 3) to protect the installation down to a temperature of 10 K below the lowest temperature likely to
occur at the installation site (for example if the minimum forecast temperature is –13°C, must be considered a
temperature of –23°C). If the unit is switched off and if the above-mentioned precautions are not followed, it is
recommended to drain the hydraulic circuit.
Damage due to freezing is not covered by the warranty.
Microprocessor ALZ 011.1 ÷ 020.1
Compact µchiller is a versatile electronic controller as compact as a standard thermostat, specifically designed for
the control of heat pumps.
Main functions
•Control of water temperature at evaporator inlet (inlet air)
•Time-based and/or temperature-based defrosting cycles
•Control of fan speed
•Full alarm management
•Can be linked up to serial line for supervisory telemaintenance control
•Can be linked up to an external terminal unit
Controlled devices
•Compressor
•Condensation fans
•Water pump or supply fan (air-to-air)
•Antifreeze heaters
•Alarm signalling device
User interface
Display -The display consists of 3 digits, with the automatic display of the decimal point between -19.9 and +
19.9°C; outside this measurement range, the value is automatically displayed without decimal (although in its
inside the machine is always operating by taking into account the decimal part). During the normal operation, the
displayed value corresponds to the temperature being read by the probe B1, that is the evaporator water inlet
temperature.
Status of the unit -The User is informed of the status of the unit by means of four LEDs on the display.
Meaning of LEDs in single-compressor units
LED Flashing Steady
Compressor Request for compressor Compressor actuated
Cooling -Cooling
Heating --
Χ100 -Visualized value x100
Parameters setting (see page 13)
Alarms and signalling
Any time an alarm condition is detected, the controller will prompt the following actions:
•the buzzer sounds
•the alarm relay energizes
•the temperature value blinks on display
•the alarm code appears on the LCD alternatively with the temperature value

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After the alarms have been cleared either with automatic reset or by pressing the and buttons simultaneously for 5
seconds (for alarms with manual reset), the controller will restore normal operating conditions:
•the buzzer turns off
•the alarm relay disenergizes
•the temperature value blinks no longer
•the alarm code disappears from the LCD
If the alarm condition persists, the actions described above will be performed again.
Alarm table
Display Tipo comp. pump fan resist. valve alarm
H1 high pressure OFF -ON --ON
L1 low pressure OFF -OFF --ON
t1overload OFF OFF OFF --ON
FL flow detector OFF OFF OFF --ON
E1,E2,E3 probe OFF OFF OFF --ON
n1 automatic timer ------
EE eeprom run ------
EL zero crossing -----ON
d1 defrosting ON ------
r1 defrosting error ------
A1 antifreeze OFF OFF --ON
LO low ambient temperature -----ON
EU low supply voltage ------
EO high supply voltage OFF OFF OFF OFF OFF OFF
EP eeprom boot OFF OFF OFF OFF OFF OFF
Cn discon. remote terminal ------
Ht high temperature -----ON
Electrical features
Power supply
Voltage supply range 24V -15%...+10% 50/60 Hz (20,4V~ 26,4 Vac)
Maximum power absorbed by the device 3 W
Characteristics of the fuse (obligatory) to be inserted in series
to the unit power supply 315mAT
Power driving
Below, as “Group A” is defined the grouping
of the following outputs valve, pump, compressor, resistance
Max. current for each power connector 2 A
Relay output current (each relay, resistive load) 2A 250 V~
Relay output current (maximum 1 relay, resistive load) 3A 250 V~
Switching maximum number (each relay) 70000
Switching maximum number (each relay) 10 s
Microprocessor ALZ 022.2 ÷ 038.2
"µchiller" is based on two integrated systems (the 'Base' section including controller, inputs and outputs, and the
'terminal' section with User Interface functions). The Base and Terminal components can be enhanced by adding
optional boards allowing further auxiliary functions.

304 C –02/06 D –pag. 9/16
Main board (single tandem)
The main board represents the core of the system, where the signals coming from the probes are processed. The
modular structure of "µchiller" allows to get great flexibility and high performance. The compressor board, for
example, can be upgraded by adding a module for the regulation of the capacity-controlled routine of the
compressor or for the activation of a second tandem.
On this board you can locate clockwise the following connection “areas”:
•Gand G0 terminals for power source connection (24Vac)
•analog inputs (from B1 to B3) for probe connection
•24V terminal (with D.C.) for the supply of any pressure probes
•digital inputs (from ID1 to ID7) for alarm connection
•jumper connector for expansion board connection
•digital relay outputs to manage any controlled device
•the Y1 GND analog output for the connection of the optional boards for the management of condensation fans
(ON/OFF regulation mode or with continuous rotation speed variation)
•telephone connector for user terminal connection
Within the board itself you can also locate other four important areas:
•the SERIAL jumper for connection of an optional serial board for the interfacing to a supervisory and/or
telemaintenance centralized system
•the KEY jumper for connection of an optional board (removable hardware key) for the immediate programming
of all data
•P1÷P5 pin-strips for the function mode selection of the analog inputs (B1÷B5)
•P6 pin-strip relative to the Y1 analog output (to be normally left open, except in particular situations –see
parameters F3 and F4).

304 C –02/06 D –pag. 10/16
The single compressor board has been designed so as to support two connected terminals, allowing therefore
data access from two different points; it can also work without any connected terminal, ensuring this way a total
safety to the data.
Second tandem board
It represents an expansion of the main board. The connection areas are the following (clockwise):
•analog inputs (B4 and B5) for the probes connection (relative to the second circuit)
•24V terminal (with D.C.) for the supply of any pressure probe
•digital inputs (from ID8 to ID11) for safety connections (relative to the second circuit)
•digital relay outputs to manage any controlled device
•the Y2 GND analog output for the connection of the optional boards for the management of condensation fans
(ON/OFF regulation mode or with continuous rotation speed variation)
•the flat cable for the connection to the single compressor main board
•P1 pin-strip relative to the Y2 analog output (to be normally left open, except in particular situations –see
parameters F3 and F4).
User Interface (Terminal)
The terminal allows the access to the data of the unit. On the terminal there are 5 LED indicators to indicate the
status of the unit, the status of the compressors (ON/OFF) and the timer for compressors/pump after 100
operating hours. An internal buzzer signals any maloperating in the unit.
Display -The display consists of 3 digits, with the automatic display of the decimal point between -19.9 and +
19.9°C; outside this measurement range, the value is automatically displayed without decimal (although in its
inside the machine is always operating by taking into account the decimal part). During the normal operation, the
displayed value corresponds to the temperature being read by the probe B1, that is the evaporator water in-let
temperature.
Status of the unit -The User is informed of the status of the unit by means of five LED indicators on the terminal
display and two LED indicators (yellow and green) placed on the main board.