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User Manual
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Contents
Chapter 1 Overview ............................................................................................................................................................ 1
1.1 Model Description ................................................................................................................................................. 1
1.2 Product Introduction..............................................................................................................................................2
1.3 Product Appearance ............................................................................................................................................. 2
1.4 Main Components.................................................................................................................................................3
1.4.1 Indoor Unit ................................................................................................................................................. 3
1.4.2 Outdoor Unit .............................................................................................................................................. 4
1.4.3 iCOM Controller.........................................................................................................................................4
1.4.4 Remote Monitoring Software .....................................................................................................................4
1.5 Environmental Requirements................................................................................................................................4
1.5.1 Operating Environment..............................................................................................................................4
1.5.2 Storage Environment ................................................................................................................................. 4
Chapter 2 Mechanical Installation ....................................................................................................................................... 5
2.1 Movement, Unpacking And Inspection.................................................................................................................. 5
2.1.1 Transportation And Movement .................................................................................................................. 5
2.1.2 Unpacking.................................................................................................................................................. 5
2.1.3 Inspection .................................................................................................................................................. 7
2.2 Installation Notes ..................................................................................................................................................7
2.3 System Installation Arrangement .......................................................................................................................... 7
2.3.1 Overall System Arrangement..................................................................................................................... 7
2.3.2 System Installation Illustration .................................................................................................................10
2.3.3 Mechanical Parameters ........................................................................................................................... 11
2.4 Installing Indoor Unit ........................................................................................................................................... 19
2.4.1 Equipment Room Requirement ............................................................................................................... 19
2.4.2 Installation Space .................................................................................................................................... 19
2.4.3 Requirement Of Maintenance Space....................................................................................................... 20
2.4.4 Installation Procedures ............................................................................................................................ 21
2.5 Installing Outdoor Unit ........................................................................................................................................ 24
2.6 Piping..................................................................................................................................................................24
2.6.1 Piping For Air-Cooled Unit ....................................................................................................................... 24
2.6.2 Piping For Water-Cooled Unit.................................................................................................................. 28
2.7 Lowering Fan And Removing Fixtures (Downflow EC Fan System) ...................................................................29
2.7.1 Downflow Unit EC Fan Lowering ............................................................................................................. 29
2.7.2 Removing Transport Fastener And Vibration Absorber ........................................................................... 31
2.8 Installation Inspection ......................................................................................................................................... 34
Chapter 3 Electrical Installation.........................................................................................................................................35
3.1 Work Introduction And Installation Notes ............................................................................................................ 35
3.2 Wiring Of Indoor Unit ..........................................................................................................................................35
3.2.1 Locating Electrical Interface Of Indoor Unit ............................................................................................. 35
3.2.2 Connecting Power Cable Of Indoor Unit.................................................................................................. 36
3.2.3 Connecting Control Cables...................................................................................................................... 37
Page 3
3.2.4 Connecting Solenoid Valve Of Pipe Extension Kit (Options, For Site Installation)................................... 38
3.3 Wiring Of Outdoor Unit (For Air-Cooled Series) .................................................................................................. 38
3.3.1 Connecting Control Signal Cables Of Outdoor Unit ................................................................................. 38
3.3.2 Connecting Power Cables Of Outdoor Unit ............................................................................................. 39
3.4 Installation Inspection ......................................................................................................................................... 39
Chapter 4 System Power-On Commissioning ................................................................................................................... 40
4.1 Location Of MCBs............................................................................................................................................... 40
4.2 Power-On Commissioning Of Air-Cooled Series................................................................................................. 41
4.2.1 Preparation Before Commissioning ......................................................................................................... 41
4.2.2 Commissioning Procedures..................................................................................................................... 42
4.2.3 Inspection After Commissioning ..............................................................................................................43
4.3 Power-On Commissioning Of Water-Cooled Series ........................................................................................... 44
4.3.1 Preparation Before Commissioning ......................................................................................................... 44
4.3.2 Commissioning Procedures..................................................................................................................... 44
4.3.3 Inspection After Commissioning ..............................................................................................................46
Chapter 5 iCOM Controller................................................................................................................................................47
5.1 LCD..................................................................................................................................................................... 47
5.2 Button And Indicator Panel ................................................................................................................................. 47
5.3 Structure Chart Of Control Menu ........................................................................................................................49
5.4 Startup Interface .................................................................................................................................................49
5.5 Main Interface ..................................................................................................................................................... 49
5.6 USER MENUS .................................................................................................................................................... 50
5.6.1 PASSWORD............................................................................................................................................ 50
5.6.2 SETPOINTS ............................................................................................................................................ 50
5.6.3 EVENT LOG ............................................................................................................................................ 50
5.6.4 GRAPHICS..............................................................................................................................................51
5.6.5 SET ALARMS..........................................................................................................................................51
5.6.6 SENSOR DATA.......................................................................................................................................52
5.6.7 DISPLAY SETUP .................................................................................................................................... 52
5.6.8 TOTAL RUN HRS.................................................................................................................................... 53
5.6.9 SLEEP MODE ......................................................................................................................................... 54
5.6.10 SERVICE INFO ..................................................................................................................................... 54
5.6.11 ACTIVE ALARMS.................................................................................................................................. 54
5.7 SERVICE MENUS .............................................................................................................................................. 54
5.7.1 PASSWORD LEVEL ............................................................................................................................... 55
5.7.2 SETPOINTS ............................................................................................................................................ 55
5.7.3 STANDBY................................................................................................................................................ 56
5.7.4 WELLNESS ............................................................................................................................................. 56
5.7.5 DIAGNOSTICS........................................................................................................................................59
5.7.6 SET ALARMS..........................................................................................................................................61
5.7.7 CALIBRATION......................................................................................................................................... 62
5.7.8 NETWORK SETUP .................................................................................................................................63
5.7.9 OPTIONS SETUP ................................................................................................................................... 64
5.7.10 SERVICE INFO ..................................................................................................................................... 65
5.8 ADVANCED MENUS .......................................................................................................................................... 65
Page 4
5.8.1 PASSWORD LEVEL ............................................................................................................................... 65
5.8.2 FACTORY SETUP .................................................................................................................................. 65
5.9 MBV Settings ...................................................................................................................................................... 69
5.10 EVENT NAME AND DEFINITION.....................................................................................................................70
Chapter 6 Application Of INTELLISLOT............................................................................................................................ 74
6.1 Introduction Of Host Communication Cards........................................................................................................ 74
6.2 Installation Of Host Communication Cards .........................................................................................................74
6.3 Commission Of Host Communication Component.............................................................................................. 75
6.3.1 Setting HyperTerminal ............................................................................................................................. 75
6.3.2 Setting 485 Communication Card ............................................................................................................ 77
6.3.3 Setting TCP/IP Communication Card ...................................................................................................... 78
6.3.4 Setting SNMP Parameters Of TCP/IP Communication Card................................................................... 80
6.4 Host Communication Networking Diagram .........................................................................................................83
Chapter 7 System Operation And Maintenance ................................................................................................................ 84
7.1 System Diagnosing Test ..................................................................................................................................... 84
7.1.1 Self-diagnosis Function ........................................................................................................................... 84
7.1.2 Electric Control Part................................................................................................................................. 84
7.2 Filter....................................................................................................................................................................86
7.3 Fan Components ................................................................................................................................................86
7.3.1 FC Fan..................................................................................................................................................... 86
7.3.2 EC Fan ....................................................................................................................................................86
7.4 Infrared Humidifier ..............................................................................................................................................86
7.5 Electric Heater ....................................................................................................................................................88
7.6 Cooling System...................................................................................................................................................89
7.6.1 Suction Pressure ..................................................................................................................................... 89
7.6.2 Discharge Pressure ................................................................................................................................. 89
7.6.3 Suction Superheat Degree ...................................................................................................................... 89
7.6.4 Thermal Expansion Valve........................................................................................................................ 90
7.6.5 Hot Gas Bypass Valve (For Single Compressor System)........................................................................ 90
7.6.6 Air-Cooled Condenser ............................................................................................................................. 91
7.6.7 Water-Cooled Condenser ........................................................................................................................ 91
7.6.8 Compressor ............................................................................................................................................. 91
Chapter 8 Troubleshooting................................................................................................................................................93
Appendix 1 Composition Of Electrical Control Box ........................................................................................................... 99
Appendix 2 Circuit Diagram............................................................................................................................................. 101
Appendix 3 Menu Structure Of iCOM Controller ............................................................................................................. 102
Page 5
Page 6
The Liebert.PEX series air conditioner is professional equipment, which should be placed away from the public.
This chapter introduces the model description, product introduction, features, main components, requirements on
transportation and storage environment of Liebert.PEX series air conditioner.
1.1 Model Description
The model description of the Liebert.PEX series air conditioner is shown in Figure 1-1.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
P2050DAS3JHL12410000P0000
Digit1 Model Range Digit16 Enclosure options
P PEX 1 Standard Color Charc oal grey
Digit2 Modules 2 Colour Special color
2 Number of Modules /Bays 6 Color Charcoal gr ey w/Double skin
Digit3 Cooling Capacity kW Digit17 Mains Switch High Voltage Option
Nominal Gross Cooling Capacity - kW 0 None
0-9
Digit4 Cooling Capacity kW D Main non-Locking Disconnect
Nominal Gross Cooling Capacity - kW
0-9
Digit5 Cooling Capacity kW
0-9
Nominal Gross Cooling Capacity - kW H Reheat & Humidity Lockout
Digit6 Air Discharge Digit19 Monitoring
U Upflow 0 Monitoring - No Card
D Downflow 1 Monitoring - IS WEB only
Digit7 System Type 2 Monitoring - Two ISW EB
A Air cooled 3 Monitoring - IS485 only
W Water cooled 4 Monitoring - Two IS485
G Glycol C ooled 5 Monitoring - ISWEB & IS485
D Dual Cool - chilled water + air cooled 6 Monitoring - iCOM DO
H Dual Cool - chilled water + water cooled D Monitoring - ISWEB & iCOM DO
F Free cool E Monitoring - Two ISWEB & iCOM DO
C Chilled Water F Monitoring - IS485 & iCOM DO
R Chilled Water - Dual Source G Monitoring Two IS485 & iCOM DO
Digit8 Airflow
1 EC Plug fan - Standard Static Digit20 Sensors
S Forward Curved fan - Standard Static 0 None
Digit9 Power Supply
3 400V / 3ph / 50Hz+N H High Temperature
T 380V / 3ph / 60Hz N Hot and Cold Isle Sensor A & Sensor B
A 460V / 3ph / 60Hz F Smoke & High Temp
Digit10 Cooling System Digit21 Packaging
C Compliant Scroll Single Circuit R407C P Packaging - Standard
S Compliant Scroll Dual Circuit R407C C Packaging - Wooden crate Export
E Digital Scroll Single Circuit R407C
D Digital Scroll Dual Circuit R407C A SFA - none
J Compl iant Scroll Single Circuit R22 Z For Internal Use Only(For Austral ia and New zealand)
F Compliant Scroll Dual Circui t R22 T For Internal Use Only(China Tele com)
2 CW Two way Valves Standard Pressure C For Internal Use Only(Chat Union)
3 CW Three way Valves Standard Pressure Digit23 Order Identifier
Digit11 Humidification 0None
0 None 1 High ESP 100 Pa
H Infrared Humidifier 2 High ESP 200 Pa
S Electrode humidifier 3 High Airflow/ESP other
Digit12 Display
S Small Display 1 TH Sensor
L Large Display 1 TH sensor 0 None
Digit13 Re-Heating L Air Cooled-Long Pipe Run Kit>30 meters
0 None X SFA Included
1 Electric heatin g Std 1 Stage
2 Electric heatin g Opt. 2 Stage Up 0 None
Digit14 Filtration
2 G4 (EU4) gravimetric (ref MERV 8) + Clogged Filter
3 F5 (EU5) dust s pot + Clogged Filter
Digit15 Coil and Valves
S
Standard DX Air Cooled Coil
4
Coil DX - All valves High Pressure MBV,DX - 2 way, CW coil 2 way
K
Coil DX - All valves High Pressure MBV,DX - 3 way, CW coil 3 way
N
Coil DX - All valves High Pressure MBV,DX - 2 way, CW coil 3 way
P
Coil DX - All valves High Pressure MBV, DX - 3 way,CW coil 2 way
Chapter 1 Overview 1
Chapter 1 Overview
Digit18 Lock Out Low Voltage Option
0None
H Monitoring - ISWEB & IS485 & iCOM DO
S Smoke Sensor
(In addition to Standard Sensor)
Digit22 Special Requirements
X SFA Included
Digit24 Order Identifier
Digit25 Order Identifier
X SFA Included
Figure 1-1 Model description
Liebert.PEX2 Series Air Conditioner User Manual
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2 Chapter 1 Overview
1.2 Product Introduction
The Liebert.PEX series air conditioner is a medium-large sized precision environment control system, which is suitable
for the environment control of the equipment room or computer room. It aims to provide a sound operating
environment for precision equipment, such as sensitive equipment, industry processing equipment, communication
equipment and computers.
The Liebert.PEX series air conditioner features high reliability, high sensible heat ratio and large airflow. It is
configured with an infrared humidifier adjustable to different water qualities, and is compatible with R407C green
refrigerant to meet the international requirement.
The unit is classified into dual cooling system, single source cooling system and free cool system in the light of the
function module. All kinds of different function systems can use the forward centrifugal curved fan (FC fan for short)
and the speed adjustable DC electronically commutated fan (EC fan for short).
Dual cooling system
The unit contains the compressor refrigerating system and the chilled-water system. The control board can select
whether to run under the compressor refrigerating system or the chilled-water system flexibly according to the
connected chilled-water condition and the indoor load, so as to achieve the energy-saving operation of the unit.
Single source cooling system
The unit contains the compressor refrigerating system only.
Free cool system
The unit contains the compressor refrigerating system and the free cool system. Free cool system can be connected
with the special dry cooler. Under the conditions of the low outdoor temperature, the unit can select whether to run
under the compressor refrigerating system or the free cool system flexibly according to the free cool medium condition
provided by dry cooler and the indoor load, so as to achieve the energy-saving operation of the unit. According to the
cooling mode of the refrigerant side, the unit contains the air-cooled series and the water-cooled series.
Air-cooled series
The Liebert.PEX air-cooled series air conditioner comprises indoor unit and outdoor unit. With the standard
configuration of Liebert.PEX condenser unit, it can reduce noise pollution to the minimum while meeting system
cooling requirement through the pressure regulating the fan speed. The Liebert.PEX low temperature CS (D) F_S
series outdoor unit can also be configured for it, qualifying the system to normally operate in cooling mode at the
temperature down to -84.2°F. Please consult Emerson Network Power Co., Ltd. (Emerson for short) if the lower
temperature is required.
Water-cooled series
The Liebert.PEX water-cooled series air conditioner uses integrated structure and highly effective brazed-plate heat
exchanger (BPHE), thus it is compact, efficient and quiet.
1.3 Product Appearance
Taking the two-bay unit of FC fan for example, the appearance of the Liebert.PEX series air conditioner is shown in
Figure 1-2.
Upflow
Figure 1-2 Appearance (two-bay unit)
Downflow
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1.4 Main Components
The main components of Liebert.PEX air conditioner include indoor unit, outdoor unit and iCOM controller.
1.4.1 Indoor Unit
The indoor unit of the Liebert.PEX air conditioner includes compressor, evaporator, thermal expansion valve, infrared
humidifier, fan, electric heater, sight glass and filter drier. Besides these components, the water-cooled series indoor
unit also includes BPHE and electric valve.
Compressor
The highly effective Copeland scroll compressor is used, featuring low vibration, low noise and high reliability. The
Rotalock connection mode makes the maintenance easier.
Evaporator
The finned tube evaporator with high heat dissipation efficiency is used. The distributor is designed and validated
according to specific model to ensure that the refrigerant is distributed evenly in each loop, improving the evaporator
efficiency to a great extent.
Thermal expansion valve
The external equalizer type thermal expansion valve is used. It can collect temperature and pressure signals at the
same time, so that it can regulate the refrigerant flow more accurately.
Infrared humidifier
Chapter 1 Overview 3
The infrared humidifier is designed with a simple structure, which is easy for teardown, cleaning and maintenance.
Application of the infrared humidifier can reduce the dependence on water quality. It also features fast startup, short
humidifying time, large humidifying capacity and high humidifying efficiency.
Fan
The forward centrifugal fan with high efficiency and high reliability can be used. It features large airflow, long blowing
distance, belt transmission and convenient maintenance. Users can also select the EC fan, which features high
efficiency, energy-saving, space-saving and low noise. EC fan unit uses elaborate structure design, and the downflow
unit uses the ‘in-floor’ design, which positions the fan unit below the floor to further improve the efficiency of air supply.
Electric heater
The spiral fin U-type stainless steel heater is used. It features fast heating speed and even heat.
Sight glass
The sight glass is the window of the system cycle, for observing the refrigerant state, mainly the moisture content of
the system. When the moisture content exceeds the standard, the color will be changed.
Filter drier
The filter drier eliminates the moisture effectively in the system, and also filtrates the impurities generated during the
long-term system operation so as to ensure normal system operation.
BPHE (for water-cooled series)
The brazed plate auto-cleansing BPHE is used. It features compact structure and high heat exchanging efficiency.
Rotalock connections are provided for water and refrigerant sides.
Electric valve (for water-cooled series and chilled water system)
Water-cooled series: The precise electric valve is used. The water flow in the BPHE can be regulated through the
intelligent valve position control of the control board, so as to ensure stable system operation.
Chilled water system: The electric valve provides proportional regulation of chilled water flow according to the cooling
requirement.
Union mode is used to connect the electric valve to the system pipeline, which is convenient for installation at site and
maintenance, reducing the project installation expenses.
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4 Chapter 1 Overview
1.4.2 Outdoor Unit
The outdoor unit is applicable to the Liebert.PEX air-cooled series air conditioner. For details, refer to Liebert.PEX
Condenser User Manual.
1.4.3 iCOM Controller
The iCOM controller of the Liebert.PEX series air conditioner uses the LCD screen with blue backlight and 128 × 64
pixels, or selects the large screen with 320 × 240 pixels. The user interface operation is simple. The multi-level
password protection can effectively prevent unauthorized operation. It also provides power failure auto-restoration and
high & low voltage protection functions. The operation time of components is available through the menus. The
expert-level fault diagnosis system can automatically display the current fault information, facilitating the maintenance.
It can store up to 400 historical event records. There are two kinds of panels for option: one with common screen and
the other with large screen, as shown in Figure 1-3.
Common screen Large screen
Figure 1-3 Panel of iCOM controller
1.4.4 Remote Monitoring Software
Through the configured RS485 port or TCP/IP port, the Liebert.PEX air conditioner can communicate with the host
computer and receive the control of the host software.
1.5 Environmental Requirements
1.5.1 Operating Environment
See Table 1-1 for operating environment requirement.
Table 1-1 Operating environment requirement
Item Requirement
Ambient temperature
Protection level (outdoor unit) IP55
Altitude <1000m. Above that, derating is required
Operation voltage range 380V (-10% ~ +15%), 3 phase+neutral ~ 50Hz
Indoor 0°C ~ 40°C
Outdoor Water-cooled series: 4°C ~ 45°C; Air-cooled series:-48°C~ +45°C
1.5.2 Storage Environment
See Table 1-2 for storage environment requirement.
Item Requirement
Storage environment Indoor, clean, no dust
Ambient humidity 5%RH ~ 85%RH (non-condensing)
Ambient temperature -68°F ~ +129.2°F
Storage time
Table 1-2 Storage environment requirement
Total transportation and storage time should not exceed six months. Otherwise, the performance needs
to be re-calibrated
Liebert.PEX2 Series Air Conditioner User Manual
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Chapter 2 Mechanical Installation
This chapter introduces the mechanical installation of the Liebert.PEX series air conditioner, including the
transportation, movement, unpacking, inspection, installation notes, system installation arrangement, installing indoor
unit, installing outdoor unit, piping for unit, lowering fan, removing fixtures and installation inspection.
2.1 Movement, Unpacking And Inspection
2.1.1 Transportation And Movement
Railroad transportation and shipping are the recommended means of transportation. If truck transportation is
unavoidable, choose roads that are less bumpy in order to protect the equipment.
The Liebert.PEX series air conditioner is heavy (see Table 2-1 for the weight). It is recommended to use mechanical
equipment such as an electric forklift to unload and move the equipment to the place closest to the installation site. If
an electric forklift is used, insert the tines of the forklift below the pallet, as shown in Figure 2-1. Align the tines with the
center of gravity to prevent the equipment from falling over.
Chapter 2 Mechanical Installation 5
When moving the indoor unit, keep the obliquity within the range from 75° to 105°, as shown in Figure 2-2.
2.1.2 Unpacking
Move the equipment to the place closest to the final installation site and then unpack it.
Follow the procedures below for unpacking:
Figure 2-1 Inserting and movement
1
0
5
Figure 2-2 Moving obliquity of indoor unit
7
5
Liebert.PEX2 Series Air Conditioner User Manual
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6 Chapter 2 Mechanical Installation
1. Remove the side panels and top cover
Liebert.PEX series air conditioner uses the international packaging. You can use a hammer or straight screwdriver to
straighten the connection hook that connects the side panels to the top cover, as shown in Figure 2-3.
At first, straighten all the hooks that fix side panel I, and remove side panel I. Then straighten all the hooks that fix side
panel II, and remove side panel II. At last remove top cover III, as shown in Figure 2-4.
Figure 2-3 Straightening the hook
III
I
II
II
1816 x 976 x 2175mm
1790 x 950 x 2020mm
Kg
I
Figure 2-4 Removing side panels and top cover
2. Remove the base pallet.
The unit is fixed onto the base pallet with M10 × 70 fixing bolts, as shown in Figure 2-5. You can use a 17mm open-end
spanner, ratchet spanner or sleeve to remove the fixing bolts.
Fixed screw on base pallet (M10 70)
Fixing bolt on base pallet (M10 70)
Figure 2-5 Fixing bolt on the base pallet
Liebert.PEX2 Series Air Conditioner User Manual
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2.1.3 Inspection
After receiving the product, you should unpack it, and then check against the packing list that the fittings are complete
and that the components are intact. If any parts are found missing, or damaged, please report to the carrier
immediately. If any defects are found, please report to the local offices of the carrier and the distributor.
2.2 Installation Notes
To achieve the designed performance and maximize the product life, the correct installation is vital. This section should
be applied in conjunction with the prevailing industry standards of mechanical and electrical installation.
1. The Liebert.PEX air-cooled series air conditioner is designed for split floor installation. The indoor unit must be
installed on the floor of the equipment room or computer room, and the outdoor unit can be installed outdoors or on the
floor of other rooms. The Liebert.PEX water-cooled series air conditioner is designed for integrated floor installation. It
should be installed on the floor of the equipment room or computer room.
2. Before installation, make sure that the installation environment meets the requirements (see 1.5 Environmental
Requirements) and confirm whether the building needs to be transformed to accommodate the construction work of
piping, wiring layout and ventilation ducts.
3. Follow the design drawings strictly when installing the equipment, and reserve the space for routine maintenance
and servicing. The manufacturer’s engineering dimension drawings can serve as a reference.
2.3 System Installation Arrangement
Chapter 2 Mechanical Installation 7
2.3.1 Overall System Arrangement
The Liebert.PEX series air conditioner includes air-cooled series and water-cooled series, and their overall system
arrangements are shown in Figure 2-6 and Figure 2-7 respectively.
Liebert.PEX2 Series Air Conditioner User Manual
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8 Chapter 2 Mechanical Installation
Balancing valve or isolation valve*
Filter*
Isolation valve*
Isolation valve*
Drain valve*
Hose port*
Welding port of chilled water in/out port
Cooling water or glycol liquid
3-way
ball valve
Chilled
water coil
Low pressure
sensor
Evaporator
Liquid
distributor
EC/FC fan
Compressor Compressor
High pressure
sensor
Refrigerant
Refrigerant
Air-cooled condenser
Air-cooled outdoor
Sight glass
FAN
Filter
drier
Expansion valve
HP
sensor
HP
sensor
BPHE
Hose port*
Welding port of chilled water in/out port
iCOM
control
Chilled
water coil
Liquid
Evaporator
distributor
EC/FC fan
Sight glass
Filter
drier
Air-cooled condenser
Air-cooled outdoor
FAN
Refrigerant
Refrigerant
BPHE
Low pressure
sensor
High pressure
sensor
3-way ball
valve
iCOM
control
condenser water
or glycol liquid
Water-cooled or
glycol-cooled
condenser water
or glycol liquid
3-way ball
valve
iCOM
control
Water-cooled or
glycol-cooled
Figure 2-6 Dual system diagram of unit
Note
MUST ENSURE THAT MECHANICAL FILTER/STRAINER IS FITTED TO INLET OF BPHE CIRCUITS BY INSTALLER!
Liebert.PEX2 Series Air Conditioner User Manual
Page 14
Balancing valve or isolation valve*
Filter*
Chapter 2 Mechanical Installation 9
Low pressure sensor
Compressor
High pressure sensor
Isolation valve*
Drain valve*
Hose port*
Welding port of chilled water in/out port
Chilled
water coil
Evaporator
Liquid
distributor
EC/FC fan
Hot gas
bypass valve
Sight glass
Filter drier
Welding port of chilled water in/out port
3-way ball
valve
Chilled
water coil
Evaporator
Liquid
distributor
EC/FC fan
Expansion valve
HP
sensor
Isolation valve*
Hose port*
iCOM control
Refrigerant
FAN
Air-cooled condenser
Air-cooled outdoor
Refrigerant
BPHE
3-way ball
valve
iCOM control
Condenser water
or glycol liquid
Water-cooled or
glycol-cooled
Figure 2-7 Single system diagram of unit
Liebert.PEX2 Series Air Conditioner User Manual
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10 Chapter 2 Mechanical Installation
Note
1. The contents in the dotted line boxes are the water-cooled unit and air-cooled unit condenser schematic diagram that divided
by the cooling mode of the refrigerant system. Select the corresponding pipe connection according to the actual type in use, the
dashed lines are for pipe connection at site, * components can be selected according to the actual requirements.
2. High pressure sensor is used for water-cooled or glycol-cooled unit only.
3. Single source cooling system does not contain the chilled water pipe system, and meanwhile, the low pressure sensor is
replaced with the low pressure switch on the side of the refrigerant.
2.3.2 System Installation Illustration
The installation modes of the air-cooled series unit are shown in Figure 2-8 and Figure 2-9.
Note
1. If the condenser is installed higher than the compressor (see Figure 2-8), a back bend should be fitted to the discharge line and
liquid line of the condenser, so as to prevent the liquid refrigerant from flowing back when the condenser stops.
2. The top end of the back bend must be installed higher than the highest copper pipe of the condenser.
Max.20m
Outdoor unit
Max.7.5m
Back bend (higher than the highest copper pipe of condenser)
Liquid line (do not expos e liquid line to sunshine)
Trap
Slope discharge
Sealed
Figure 2-8 Condenser installed higher than compressor
Heat insulation floor
Indoor unit
Floor
Raised floor
Humidifier water in
Condensed water out
Condensate drain
supply
Liebert.PEX2 Series Air Conditioner User Manual
Page 16
Indoor unit
Chapter 2 Mechanical Installation 11
Sealed
Slope discharge
Raised floor
Slope liquid
Min. 5m
Max.
Heat insulation floor
Floor
Humidifier water in
Condensate drain
Condenser water out
Condensed water out
supply
Outdoor unit
Figure 2-9 Compressor installed higher than condenser
Figure 2-10 shows the arrangement of the cooling water system, which requires the water hotter than 4°C. Use
heaters if the water source in site cannot meet this requirement. The cooling tower should be a closed loop system.
Closed cooling tower
Exha ust wate r va lve
Strainer
Expansion water tank
Supplementary valve
Manometer
P
T
Temperature
gauge
Liebert.PEX-T unit
unit
M
Filter Pump
2.3.3 Mechanical Parameters
Indoor unit mechanical parameters
The mechanical parameters of the indoor unit are shown in Figure 2-11, Figure 2-12, Figure 2-13 and Table 2-1.
P
T
Figure 2-10 Arrangement of cooling water system
Liebert.PEX2 Series Air Conditioner User Manual
P
T
Drain valve
Ball
valve
Page 17
12 Chapter 2 Mechanical Installation
8
8
5
53
3
1970
1970
8
8
5
53
3
1970
1970
4
7
874
8
One-bay upflow
1
1
7
0
7
4
0
4
1970
1970
4
4
7
7
8
8
Two-bay upflow
One-bay downflow
Two-bay downflow
4
7
8
874
1
1
7
7
0
0
4
4
1970
1970
4
4
7
7
8
8
2
2
5
5
5
5
3
3
1970
1970
4
4
7
7
8
8
Three-bay upflow Three-bay downflow
Three-bay downflow
Before installing the filter
Figure 2-11 Mechanical parameters of the indoor FC fan unit (unit: mm)
Liebert.PEX2 Series Air Conditioner User Manual
25
2
5
5
5
3
3
2
2
5
5
5
5
3
3
1970
1970
1970
1970
4
4
4
4
7
7
7
7
8
8
8
8
Page 18
Chapter 2 Mechanical Installation 13
17
1
7
04
0
87
8
85
53
3
1970
1970
4
4
7
8
4
1970
1970
4
4
7
8
87
Two-bay upflow
Two-bay upflow
2
2
55
5
53
3
1970
1970
4
4
7
8
87
Three-bay upflow
Figure 2-12 Mechanical parameters of the indoor EC fan upflow unit (unit: mm)
Note
The indoor unit mechanical parameters of EC fan downflow unit are the same as those of FC fan unit (except for P3100 and
P2070 downflow dual cooling units, see Figure 2-13 for its mechanical parameters).
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14 Chapter 2 Mechanical Installation
Three-bay downflow
Before installing the filter
Before installing the filter
Figure 2-13 Mechanical parameters of P3100 downflow dual cooling indoor unit (unit: mm)
25
2
55
53
2
2
2
2
5
5
5
55
5
5
53
3
3
3
1970
1970
1970
1970
4
4
7
7
8
8
4
4
7
7
8
8
After installing the filter
3
2070
2070
4
4
7
8
87
Note
For P3100 and P2070 downflow dual cooling series units, the filter is delivered along with the unit accessory, therefore, the unit
integral height can be increased to 100mm after installation. Taking P3100 for example, you can see the left figure of Figure 2-13
for dimensions of the filter before the installation and see the right figure of Figure 2-13 for dimensions of the filter after the
installation.
Table 2-1 Mechanical parameters of indoor unit
Net weight (kg)
Model
P1020 853 × 874 × 1970 320 420 320 420
P1025 853 × 874 × 1970 330 430 330 430
P1030 853 × 874 × 1970 340 440 340 440
P1035 853 × 874 × 1970 350 450 350 450
P2035 1704 × 874 × 1970 550 700 550 700
P2040 1704 × 874 × 1970 590 740 590 740
P2045 1704 × 874 × 1970 560 710 560 710
P2050 1704 × 874 × 1970 610 760 610 760
P2055 1704 × 874 × 1970 570 720 570 720
P2060 1704 × 874 × 1970 640 790 640 790
P2070* 1704 × 874 × 1970 650 800 650 800
P3070 2553 × 874 × 1970 890 1090 890 1090
P3080 2553 × 874 × 1970 910 1110 910 1110
P3090 2553 × 874 × 1970 930 1130 930 1130
P3100* 2553 × 874 × 1970 950 1150 950 1150
Note:
The model with * means that the downflow dual cooling series units will be increased to 100mm after installation
Dimensions (W × D × H)
(mm)
Single source
cooling system
Air-cooled series Water-cooled series
Dual cooling
system
Single source
cooling system
Dual cooling
system
Note
The weight of free cool system unit is the same as that of the dual cooling system unit.
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Chapter 2 Mechanical Installation 15
Plenum dimensions
You can select the air supply plenum with grids for the upflow system according to the requirement. The appearance of
the plenum is shown in Figure 2-14, Figure 2-15 and Figure 2-16. The dimensions are listed in Table 2-2.
A
Figure 2-14 One-bay plenum Figure 2-15 Two-bay plenum
A
B
C
A
B
B
C
C
Figure 2-16 Three-bay plenum
Table 2-2 Plenum dimensions
A B C
Type
One-bay plenum
Two-bay plenum
Three-bay plenum
867
867
867
853
1704
2553
400 (600, optional)
400 (600, optional)
400 (600, optional)
Note
If the height of the plenum selected for air conditioner unit exceeds 600mm, consult Emerson for non-standard production.
Outdoor unit mechanical parameters
See Liebert.PEX Condenser User Manual for the dimensions and mechanical parameters of the outdoor unit.
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16 Chapter 2 Mechanical Installation
Base pallet cutout locations & dimensions
Figure 2-17 and Figure 2-18 show the bases with the side panel removed.
230
D
C/R
100
128.8
H
CI
136.8
78.8
D
H
134
108.5
134.5
126
C/R
CI
One-bay series
CO
P
1133
Two-bay series
60
58
78.8
C/R
149
255
100 130
CO
P
60
103.5
D
H
230
134
108.5
134.5
126
C/R C/R
CI
1133
1700
Three-bay series
100
60
130
850
100
CO
P
P: Power cable entry hole D: Drain
H: Humidifier water in CI: Chilled water in
CO: Chilled water out C/R: Cooling water in or out/Refrigerant in or out
Figure 2-17 Base cutout location of upflow models (unit: mm)
128.8
60
58
78.8
149
255
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65
170
Chapter 2 Mechanical Installation 17
Fan aperture
93
D
CO
CI
H
C/R
P
FC fan EC fan
332
240
140
One-bay series
65
170
Fan aperture
CO
CI
C/R
93
332
P
240
140
350
Fan aperture Fan aperture
CI
D
C/R
H
1513
FC fan
Fan aperture
CI
C/R
H
CO
C/R
Fan aperture
CO
C/R
93
93
140
140
240
240
332
332
P
P
350
350
242
242
83
140
83
140
1513
EC fan
Two-bay series
Fan aperture
CI
D
242
C/R
H
140
Fan aperture
FC fan
Fan aperture
CO
C/R
93
332
P
240
140
CI
Fan aperture
350
242
C/R
H
140
94 1513
Fan aperture
EC fan
Three-bay series
Fan aperture
CO
C/R
850.2
93
P
240
140
P: Power cable entry hole D: Drain
H: Humidifier water in CI: Chilled water in
CO: Chilled water out C/R: Cooling water in or out/Refrigerant in or out
Figure 2-18 Base cutout location of downflow (unit: mm)
Fan aperture locations & dimensions of top cover
The top cover fan aperture locations of upflow unit are shown in Figure 2-19.
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Page 23
18 Chapter 2 Mechanical Installation
400
254
509
800
FC fan
210 400 430 400
254509
1650
FC fan EC fan
210 400 430 400 498 400
794.8
40
One-bay upflow series
794.8
40
Two-bay upflow series
720
800
EC fan
1650
740.5 740.5
89
724.8
35
724.8
35
254509
2498
FC fan
794.8
40
740.5 740.5 720
89
2498
EC fan
Three-bay upflow series
128
Figure 2-19 Top cover fan aperture locations of upflow series (unit: mm)
724.8
35
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Page 24
Side panel cutout locations & dimensions
If piping and wiring from the base are difficult, connection from the side panel can be selected. The locations and
dimensions of the knock-out holes are shown in Figure 2-20. You can select the in and out holes according to the
actual needs, but must confirm that any two of the pipe, power cable and signal cable cannot use the same hole.
knock-out hole
8-Ф80
knock-out hole
2-Ф35
Figure 2-20 Cutout positions of side panel (unit: mm)
2.4 Installing Indoor Unit
2.4.1 Equipment Room Requirement
319
419
519
673.68
Chapter 2 Mechanical Installation 19
knock-out hole
2-Ф25
7
8
1
7
13 7
8
The requirements of the equipment room are as follows:
1. Damp proof and heat preservation work must be well done to make sure that the environment control system in the
air conditioner room can operate normally.
2. The equipment room should have good heat insulation and sealed damp proof layer. The damp proof layer of the
ceiling and walls must use polyethylene film, and the coating of the concrete wall and the floor must be damp proof.
3. The outdoor air that enters the equipment room should be reduced to a minimum, better below 5% of the total
indoor airflow, as it may increase the load of heating, cooling, humidifying and dehumidification of the system.
4. All the doors and windows should be closed and the openings should be as narrow as possible.
2.4.2 Installation Space
Note
The air conditioner can generate condensate, which may be leakage due to the incorrect installation or use. Do not install it in the
vicinity of any precision equipment so as to maintain the normal operation, and the installation site must provide drain pipes.
1. To ensure normal operation, adequate installation space for the indoor unit must be provided.
2. Avoid locating the indoor unit in confined areas, which can baffle the airflow, shorten the cooling cycle and result in
down-draft and air noise.
3. Avoid locating the indoor unit in a concave or at the end of a long and narrow room.
4. Avoid locating multiple indoor units close to each other. That can result in crossing air patterns, unbalanced load and
competitive operation.
5. For the convenience of daily maintenance, do not install other devices (such as smoke detector) over the cabinet.
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20 Chapter 2 Mechanical Installation
2.4.3 Requirement Of Maintenance Space
Leave a maintenance space of 850mm in front of the air conditioner unit normally, as shown in Figure 2-21.
m
m
0
5
8
Figure 2-21 Maintenance space
The minimal maintenance space is required as listed in Table 2-3.
Table 2-3 Minimal maintenance space (unit: mm)
Position Air-cooled Water-cooled
Front
Left
Right
Back
Note :
1. The space is provided for regular maintenance, such as replacing strainer, adjusting fan, cleaning infared humidifier.
2 *. They are the maintenance space when the water-cooled unit connects water pipes on side or when the air-cooled unit connects
the refrigerant pipes on side. If the water pipes or refrigerant pipes are laid on the bottom of the unit, no maintenance space is
required
Note
For special applications, please consult Emerson.
600
600*
600*
0
600
600*
600*
0
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Page 26
2.4.4 Installation Procedures
The installation procedures of the indoor unit are as follows:
1. Make a mounting base according to the dimensions in Figure 2-22, Figure 2-23 and Figure 2-24, and the
requirements in Table 2-4. Emerson can supply a range of mounting bases to suit the required height.
2. Lay a layer of rubber cushion on the top, lateral of the mounting base and on the bottom of the steel plate
respectively. See Figure 2-22, Figure 2-23 and Figure 2-24 for their positions and see Table 2-4 for the thickness.
3. Determine the installation position. Fix the mounting base onto the mounting position according to the site
conditions and user’s requirement.
4. Fix the air conditioner cabinet onto the mounting base with nuts, spring washers, flat washers and bolts.
Chapter 2 Mechanical Installation 21
Installation hole of 4-M8×60 sems screw
Rubber cushion (lateral)
Rear side of cabinet
Figure 2-22 Mounting base appearance and dimensions of one-bay series (unit: mm)
8
9
7
4
6
7
7
8
8
9
3
9
2
6
1
0
0
Installation hole of 4-M8 ancho r bolt
8
5
0
6
9
4
8
5
7
Base
Front side of cabinet
4
0
Angle steel
Rubber cushion (top)
H
Rubber cushion (bottom)
Steel plate
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22 Chapter 2 Mechanical Installation
Installation hole of 4-M8×60 sems screw
Rubber cushion (lateral)
Steel plate
Rear side of cabinet
8
9
7
4
6
7
1
7
4
1
3
7
7
6
Upflow
Installation hole of 4-M8×60 sems screw
8
9
7
4
6
7
Installation hole of 4-M8 anchor bolt
Front side of cabinet
1
7
0
0
1
5
4
4
4
0
Rubber cushio n (top)
H
7
8
8
5
1
0
0
1
7
0
0
1
5
4
4
7
Base
Front side of cabinet
Rubber cushio n (bottom)
Angle steel
Rubber cushion (lateral)
Steel plate
Rear side of cabinet
Figure 2-23 Mounting base appearance and dimensions of two-bay series (unit: mm)
Downflow
4
0
Rubber cushio n (top)
H
1
7
4
1
3
7
7
6
7
8
8
5
1
0
0
Installation hole of 4-M8 anchor bolt
7
Base
Rubber cushio n (bottom)
Angle steel
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Page 28
Installation hole of 6-M8×60 sems screw
Chapter 2 Mechanical Installation 23
Rubber cushion
(lateral)
Steel plate
Rear side of cabinet
8
9
7
6
7
4
Upflow
Front side of cabinet
1
6
8
0
1
5
4
4
2
5
9
3
2
6
2
6
2
5
5
0
8
5
0
7
8
58
1
0
0
Installation hole of 4-M8 anchor bolt
7
Base
4
0
Rubber cushion
(top)
H
Rubber cushion
(botto m)
Angle steel
Rubber cushion
(lateral)
Steel plate
Installation hole of 6-M8×60 sems screw
Rear side of cabinet
8
9
7
6
7
Figure 2-24 Mounting base appearance and dimensions of three-bay series (unit: mm)
4
Downflow
Front side of cabinet
1
6
8
0
1
5
4
4
25
9
3
2
6
2
6
2
5
5
0
8
5
0
7
8
8
10
0
Installation hole of 4-M8 anchor bolt
75
Base
4
0
Rubber cushion
(top)
H
Rubber cushion
(bottom)
Angle steel
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24 Chapter 2 Mechanical Installation
Table 2-4 Specifications of indoor unit mounting base
Item Specification Remark
Steel plate 100mm × 100mm × (5 ~ 6.5)mm -
Angle steel 40mm × 40mm × 3mm -
Rubber
cushion
Installation hole of
anchor bolt
Top Thickness: 3mm ~ 5mm Supplied by others
Lateral Thickness: 2mm ~ 3mm Supplied by others
Bottom Thickness: 10mm ~ 12mm Supplied by others
- Install the bolts according to your requirement
One-bay
H
Note:
The external side boards of the unit cannot bear weight. Take the mounting base into consideration while selecting angle steels
and fixing holes. For the downflow unit used EC fan, the minimum floor height requirement must be met
Two-bay
Three-bay
H = 200mm (upflow unit)
H ≥ 300mm (downflow unit of
forward curved fan)
H ≥ 325mm (downflow unit of EC
fan)
2.5 Installing Outdoor Unit
This outdoor unit is only applicable to the air-cooled series air conditioner. For detailed installation, refer to Liebert.PEX
Condenser User Manual.
2.6 Piping
2.6.1 Piping For Air-Cooled Unit
All joints of the cooling pipes must be silver-brazed. Standard industry procedures must be followed in selecting, laying,
and fixing the pipes, and evacuating the system and charging refrigerant. Take pipeline pressure drop, oil return to the
compressor and minimization of noise and vibration into consideration during design and construction.
General
1. Only three-bay unit needs the middle support (front and rear).
2. The upflow unit does not need the flow deflector.
3. The H dimension here is only for reference, and should be
determined according to user’s actual requirement while
making the base
The recommended pipe sizes are ‘equivalent lengths’ (see Table 2-6 for equivalent lengths of partial components),
with the resistance caused by bends taken into account. The installer should confirm that the sizes are appropriate for
the site conditions.
1. If the one-way equivalent length exceeds 30m, or if the vertical distance between indoor unit and outdoor unit
exceeds the values in Table 2-5, consult Emerson before installation to confirm whether a pipe extension kit is needed.
Table 2-5 Vertical distance between indoor unit and outdoor unit
Relative position altitude difference
Outdoor unit higher than indoor unit Max.: +20m
Outdoor unit lower than indoor unit Max.: -5m
2. The pipe sizes recommended in Table 2-6 are ‘equivalent lengths’, with the resistance caused by bends and valves
taken into account. The installer should confirm that the sizes are appropriate for the site conditions.
Table 2-6 Equivalent lengths of partial components
Outer Diameter (OD) of
liquid pipe (inch)
3/8 0.21 0.10 0.76
1/2 0.24 0.12 0.76
5/8 0.27 0.15 0.76
3/4 0.3 0.18 0.76
7/8 0.44 0.24 1.1
1-1/8 0.56 0.3 1.4
90° bend 45° bend T type three-way
Equivalent length (m)
Liebert.PEX2 Series Air Conditioner User Manual
Page 30
Chapter 2 Mechanical Installation 25
r
Note
A trap should be installed for every 7.5m of vertical distance. Please consult Emerson for details.
Connecting pipes
The pipes to be connected include:
1. Condensate drain pipe of indoor unit
2. Water inlet pipe for infrared humidifier
3. Connection copper pipe (discharge pipe and liquid pipe for air-cooled system) between indoor unit and outdoor unit
4. Water inlet and outlet pipe of the chilled water (dual cooling unit)
5. Pipe extension kit (optional)
z Connecting condensate drain pipe of indoor unit
The condensate of infrared humidifier and evaporator is converged by a cross connector and drained through the drain
pipe, as shown in Figure 2-25. The pipe OD is 25mm. If the drain pipe is used by three or more units, the minimal pipe
OD should be 40mm.
Note
Because the infrared humidifier contains flowing hot water, the water pipe must be resistant to heat higher than 90°C.
Water in pipe of
ater inlet pipe of f ar
infrared humidifier
infrared humidifier
Connection of
Connector of condensed
condensate drain pipe
water drain pipe
To far infrared humidifier
To infrared humidifier
wat er p an
To condensate
o condensed wate
To condensate
pan of evaporator
pan of evaporator
To condensate
To the condensed
To condensed
drain pipe
water drain pipe
Hose clamp
Figure 2-25 Connection of drain pipe
To condensed water
pan of evaporator
pan of evaporator
Cross connector
Note
1. A Φ25 hose clamp is delivered as an accessory to connect the drain pipe.
2. When connecting the drain pipe, you must make sure that the U bend is installed vertically and the ‘U’ shape is not distorted,
so as to ensure that the condensate can be drained immediately and effectively.
z Connecting water inlet pipe of infrared humidifier
Water pipes should be connected for the infrared humidifier. To facilitate maintenance, an isolation valve should be
fitted to the water inlet pipe. The infrared humidifier reserves a copper pipe (OD: 6.35mm), as shown in Figure 2-26.
There is a 1/4” copper nut at the end of the copper pipe. Take out the 1/4” × 1/2” conversion copper thread connector
from the accessory bag and connect it to the copper nut. You can also choose the connection method to connect pipes
according to the site condition. Make sure that the connection is well sealed to prevent leakage. The main pipe
pressure should be between 100kPa ~ 700kPa.
Where the main pipe pressure may rise above 700kPa, a pressure reducer should be fitted. Where the main pipe
pressure falls below 100kPa, a water tank and pump system should be used.
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26 Chapter 2 Mechanical Installation
Note
Some product may include components required by local codes.
Over-temperature
protection switch
Water outlet
A direction
Stainless steel stud
Over-temperature
protection relay
Ceramic terminal socket
Water supply pipe
Water pan (removable)
Water supply solenoid valve
Water high level sensor
Water level sensor
Water pan fixing screw (left and right)
Water pan fixing screw
Water supply pipe
OD 6.35mm
OD 6.35mmФ
Water level regulator
A direction
Figure 2-26 Infrared humidifier
Over-temperature protection
switch (undre pan)
switch (water pan bottom)
z Connecting connection copper pipes (discharge pipe and liquid pipe) between indoor unit and outdoor unit
The indoor unit and outdoor unit are connected through welded copper pipes. The connection ball valves of the
discharge pipe/liquid pipe of indoor unit are shown in Figure 2-27 and Figure 2-28. Note that the ball valve must be
wrapped with a wet cloth before welding. In addition, many notes and instruction labels are pasted onto the base and
side panel close to the ball valve. Protect them from heat burned during the welding operation.
Note
The exposure time of system pipes do not exceed 15min. Longer exposure will lead to the POE refrigeration oil being affected
with moisture, which can affect the life of the key components and the stability of the system operation. Especially note that the
compressor and the corresponding expansion valve of the dual refrigerant system unit should be located at both sides of the unit.
For example, you face the unit front door, No.1 system compressor is on the left hand side, while the expansion valve that
corresponds to No.1 compressor is on the right hand side. Similarly No.2 system compressor is on the right hand side, while the
expansion valve that corresponds to the No.2 compressor is on the left hand side.
Horizontal sections of the discharge pipes should be sloped downward from the compressor, with a slope of at least
1:200 (5mm down for each 1m run). The discharge pipes should be insulated where they are routed in the conditioned
space (including under a raised floor).
The pressure drop should not exceed 40kPa (5psi ~6psi), provided that there is no loss of refrigeration in the liquid
return pipe. The pressure drop of the liquid return pipe is the sum of liquid flow resistance from the tubing and fitting
(including filter drier), plus the loss of head pressure due to elevation above the condenser. If the liquid temperature is
38°C, the static pressure loss is 11kPa (1.6 psi) per meter of lift.
System 2
expansion valve
System 1
System 2
System 2
expansion valve
System 1 System 2
System 1 pipe
System
System
1 sight
2 sight
glass
glass
Air-cooled of upflow
pipe
System
1 sight
glass
Water-cooled of upflow
System 2 pipe System 1
expansion valve
Figure 2-27 Pipe connection of upflow unit
System 1
Liebert.PEX2 Series Air Conditioner User Manual
System
2 sight
glass
System 2 pipe
System 1
expansion valve
Page 32
Chapter 2 Mechanical Installation 27
System 2
expansion valve
System
2 sight
System 1 pipe
glass
System 1
System 1
expansion valve
Air-cooled of downflow Water-cooled of downflow
Figure 2-28 Pipe connection of downflow unit
System 2
System
1 sight
glass
System 2
pipe
System 2
expansion valve
System
2 sight
System 1 pipe
glass
System 1 System 2
System 1
expansion valve
System
1 sight
glass
System 2
pipe
Considering the effect of the pipe diameter on the system pressure drop, the pipe diameter of the indoor unit and
outdoor unit should be determined according to the specifications listed in Table 2-7.
Table 2-7 Recommended pipe sizes
Recommended pipe sizes (unit: mm)
Model P1020 P1025 P1030 P1035 P2035 P2040 P2045 P2050
Eq.Lgt
10m 22 13 22 13 22 13 22 13 22 13 22 13 22 13 22 13
20m 22 13 22 13 22 13 22 16 22 16 22 13 22 16 22 13
30m 22 13 22 13 22 16 25 16 25 16 22 13 25 16 22 13
40m* 22 13 22 13 22 16 25 16 25 16 22 13 25 16 22 13
50m* 22 13 22 16 25 16 25 16 25 16 22 13 28 19 22 16
60m* 22 16 22 16 25 16 25 19 25 19 22 16 28 19 22 16
Model P2055 P2060 P2070 P3070 P3080 P3090 P3100
Eq.Lgt
10m 22 16 22 13 22 13 22 13 22 13 22 13 22 16
20m 25 16 22 13 22 16 22 16 22 16 25 16 25 16
30m 28 19 22 16 25 16 25 16 25 16 25 16 28 19
40m* 28 19 22 16 25 16 25 16 25 16 25 16 28 19
50m* 28 19 25 16 25 16 25 16 28 19 28 19 28 19
60m* 32 19 25 16 25 19 25 19 28 19 28 19 32 19
Note：
1. A pipe extension kit is required for ‘Eq.Lgth’ marked with *.
2. D: discharge line, L: liquid line.
3. Consult Emerson if the pipe length exceeds 60m
D L D L D L D L D L D L D L D L
h
D L D L D L D L D L D L D L
h
z Connecting water inlet and outlet pipe of the chilled water (dual cooling unit)
The water inlet and outlet pipe of the chilled water is connected to the chilled water unit through welding. The inlet and
outlet pipe of the chilled water should be welded according to the unit rack labelling, do not reverse the connection.
The water inlet and outlet pipe of the chilled water can be connected from the base pallet or side panel, see the cutout
positions schematic diagram of the base pallet and side panel for pipe entry position (see Figure 2-17, Figure 2-18,
Figure 2-20). There should be a flexible connector for water inlet and outlet pipe and unit connection. The water inlet
pipe must be installed with a strainer more than 60 mesh. The water inlet and outlet pipe of the chilled water should be
installed more than one isolation valve, so as to cut off the power upon repair. One of the isolation valves can be a
balancing valve. The chilled water system with a balancing valve has higher efficiency, and can control the water
distribution more accurately.
z Installing pipe extension kit (for site installation)
When the equivalent length of the one-way pipe exceeds 30m, the pipe extension kit should be installed. During the
installation of the pipe extension kit, to avoid the pipe opening, it is recommended to install the solenoid valve of the
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28 Chapter 2 Mechanical Installation
pipe extension kit onto the outside project pipe of the ball valve on the liquid pipe. The outer side or the bottom of the
unit is allowable.
So, during installing the solenoid valve, you do not need to cut the indoor unit pipes. After the whole system is installed,
you can open the ball valve to keep pressure and carry out the vacuum operation, avoiding the moisture absorption of
the compressor refrigeration oil and ensuring the operation safety and life of the compressor. For the installation
position of the check valve, refer to Figure 2-6.
For the electrical connections of the pipe extension kit, refer to 3.2.4 Connecting Solenoid Valve Of Pipe Extension
Kit (Options, For Site Installation).
Charging refrigerant and adding refrigerant oil
1. Charging refrigerant
The Liebert.PEX air-cooled series air conditioner has been charged in the factory with 2bar nitrogen.
If the connection pipe between the indoor unit and the outdoor unit is longer than 10m, refill the refrigerant to the
system to ensure normal system operation.
The refilling amount of the refrigerant is calculated through the following formula:
Refrigerant refilling amount (kg) = refrigerant refilling amount per unit length of liquid pipe (kg/m) × total length of
extended liquid pipe (m)
See Table 2-8 for refrigerant refilling amount of per meter liquid pipe.
Total length of extended liquid pipe (m) = Total length of liquid pipe (m) - 10m
Table 2-8 Refrigerant refilling amount per unit length of liquid pipe with different ODs
Liquid pipe OD
(mm)
9.52 0.060 19 0.261
12.7 0.112 22 0.362
16 0.181 28.6 0.618
Refrigerant refilling amount of per meter
liquid pipe (kg/m)
For the refrigerant charge quantity, refer to step 5 in 4.2.2 Commissioning Procedures.
2. Adding POE refrigerant oil
The refilled refrigerant will dilute the POE refrigerant oil in the system and affect the lubricating and cooling effects of
the POE refrigerant oil. Therefore, the POE refrigerant oil should be added. See the formula below:
Amount of refrigerant oil (ml) to be added = refrigerant refilling amount (kg) × 22.6
Liquid pipe OD (mm)
Refrigerant refilling amount of per
meter liquid pipe (kg/m)
2.6.2 Piping For Water-Cooled Unit
Each cooling system uses a BPHE (or condenser) and an electric valve. The water supply (inlet) pipe and water return
(outlet) pipe of the cooling water should be connected for the system. See Figure 2-29.
A filter (filter mesh: 1mm) and multiple isolation valves should be mounted one side of the water supply pipe of the
cooling water. One of the valves can be a balancing valve.
The cooling water system with a balancing valve can control the water distribution more accurately and its pump has
higher efficiency. On the other hand, the electric valve can keep the optimal condensing temperature by regulating the
internal water flow.
The electric actuator of the regulating valve features a manual override to allow water side balancing by the installer.
It is recommended to arrange the cooling water pipes separately for different systems, so that repairing one pipe will
not affect the operation of the other one.
The water pressure should be high enough to counteract the pressure drops brought about by all the components of
the water system. In addition, because the sediments and impurities cause more pressure drop after long term
operation, you should arrange a redundancy of 20% ~ 25% when selecting the lifting part (such as pump).
See Figure 2-6 and Figure 2-7 for the system arrangement of the water-cooled unit.
Connecting pipes
The pipes to be connected include:
1. Condensate drain pipe of indoor unit
2. Water inlet pipe of infrared humidifier
3. Water inlet and outlet pipe of cooling water
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Chapter 2 Mechanical Installation 29
4. Water inlet and outlet pipe of chilled water (dual cooling unit)
z Connecting condensate drain pipe of indoor unit
Refer to the corresponding content in 2.6.1 Piping For Air-Cooled Unit.
z Connecting water inlet pipe of infrared humidifier
Refer to the corresponding content in 2.6.1 Piping For Air-Cooled Unit.
z Connecting water inlet and outlet pipe of cooling water
The water inlet and outlet pipe of cooling water of the indoor unit are copper pipes with 35mm outer diameter, as
shown in Figure 2-29. Connect the pipes through direct welding at the site and make sure that the junction is
well-sealed.
板式换热器
BPHE
进水管
进水
出水管
出水
Water inlet
Figure 2-29 Unit connections (water-cooled)
Water outlet
z Connecting water inlet and outlet pipe of chilled water (dual cooling unit)
Refer to the corresponding content in 2.6.1 Piping For Air-Cooled Unit.
2.7 Lowering Fan And Removing Fixtures (Downflow EC Fan System)
2.7.1 Downflow Unit EC Fan Lowering
After installation, you must lower all fans of the EC downflow unit before commissioning. You lower the fan using the
supplied hand winch. Each EC downflow unit is only equipped with one lowering tool, so you should select the
lowering mode according to the equipped lowering tool.
Note
Be careful when lowering the fan, avoid trapping your fingers and fan cables, and avoid foreign matter falling into the inlet ring
of the fan.
Lowering Fan Through Hand Winch Mode
The downflow unit has been equipped with a set of fan elevator assembly before delivery, including a hand winch, a
winch bracket, a hook, a sling, a winch limit and a handle in Figure 2-30, and also an L shaped lifting component in
Figure 2-31.
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30 Chapter 2 Mechanical Installation
Wi nch bracket
Sling
Hook
Figure 2-30 Fan elevator assembly (winch mode)
Winch
Handle
Lower the fan with the fan elevator assembly installed according to the following procedures:
1. Open the unit maintenance cover, check the fixing bolts and washers II (see Figure 2-31, totally 2 pcs) of the L
shaped lifting component to make sure that it is fixed properly, and then install the fixing bolts and washers IV (totally 4
pcs) of the winch bracket, as shown in Figure 2-31.
Unit beam
Washers II
Gaskets II
Winch bracket
Middle round hole
L shaped lifting component
Unit beam
Sling
Winch
Handle
Washers IV
Gaskets IV
Fan
Figure 2-31 Installing winch bracket
2. Turn the handle and use the hook of the winch to hook the middle round hole (see Figure 2-31) of the L shaped
lifting component. Adjust the handle until the sling is completely tight.
3. Cut off the cable tie binding the fan cables to make the cables length satisfy fan lowering requirements, and then
remove the fixing bolts and washers I (see Figure 2-32, totally 4 pcs) for fan transportation.
Gaskets I
Washers I
Figure 2-32 Position of fixing bolt and washer I
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Chapter 2 Mechanical Installation 31
4. Hold the handle of the winch firmly, and then turn the handle counter-clockwise to lower the fan.
After the fan is sunk, the status is shown in Figure 2-33.
Fan installation top cover
Unit base pallet
Washers III
Gaskets III
Figure 2-33 Lowering the fan
5. Install the fixing bolts and washers III (see Figure 2-33, totally 4 pcs) of the fan.
6. Remove the hook from the L shaped lifting component, turn the handle clockwise, tidy the sling and remove the
fixing bolts and washers IV (see Figure 2-31, totally 4 pcs) of the winch bracket, and take out the winch and the bracket
assembly.
7. Remove the fixing bolts and washers II (see Figure 2-31, totally 2 pcs) of the L shaped lifting component, and take
out the L shaped lifting component.
At this point, the operation of lowering the fan of one-bay unit is completed.
For the two-bay unit and three-bay unit, you should also lower other fans using the fan elevator assembly. The detailed
procedures are given as follows:
1. Install the fixing bolts and washers II (see Figure 2-31, totally 2 pcs) to fix the L shaped lifting component and the fan
installation top cover.
2. Install the fixing bolts and washers IV (see Figure 2-31, totally 4 pcs) to fix the winch and its bracket onto the unit
beams.
3. Repeat the step 1 to step 7 of the one-bay unit to lower all fans.
4. After lowering all fans, tidy the fan cables and fix them using a cable tie.
2.7.2 Removing Transport Fastener And Vibration Absorber
To protect partial components from damaging and distorting due to bumping, impact and resonation, fasteners and
vibration absorbers are mounted at certain locations before delivery. Remove the fasteners and vibration absorbers
before installation and commissioning.
Removing transportation fixing plate of compressor
To reduce the compressor operation vibration and noise, the vibration absorbing cushions are added to the
compressor base. However, such method cannot best restrain the equipment vibration during transportation, and may
result in loosened connections and wearing of certain parts. To prevent this, three L shaped fixing plates are added to
the compressor base, as shown in Figure 2-34.
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32 Chapter 2 Mechanical Installation
After the installation and before the commissioning, remove the three L shaped fixing plates, and then restore the bolts
and washers. The fastening torque of the bolts is (12 ± 1) N.m.
Removing transportation fastener of fan
1. FC upflow unit
The motor base of the fan is designed with a semi-free self-tension structure to minimize the fan operation noise and
prolong the belt life. During the transportation, to protect the semi-free structure from failing or collapsing due to
resonation, the upflow unit is especially fastened with bolts (left and right symmetrical, one at each side), as shown in
Figure 2-35. You should cut the binding string on the belt and remove the four fixing bolts before the power-on
operation; otherwise, the fan could be damaged and even cause personal injury. It is necessary to hold the motor
firmly while you remove the fixing bolts.
Cut the binding string on the belt.
L shaped fixing plates (3 pcs)
固定钣金（共3个）Fixing plates (3 pcs)
Figure 2-34 Positions of fixing plates
Note
When you open the front door of unit, you will see a warning label concerning bolt removal on the sealing panel of the fan.
Remove the bolts by following the preceding instructions.
Transportation bolt
(one on each side)
Binding string
Figure 2-35 Fixed bolts and binding string of transport fan components
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Chapter 2 Mechanical Installation 33
2. FC downflow unit
During the transportation, some cushion foam is inserted into the triangle formed by the motor base and the fan.
Remove the foam before the power-on operation.
Note
Never put hands into the triangle gap between the motor base and fan.
Removing transportation fastener of infrared humidifier Note
1. Not removing the transport protection foam may cause fire.
2. Do not touch the lamps with bare fingers.
To protect the infrared humidifier lamps from rupturing during transportation, protection foam is fitted to the infrared
humidifier components before delivery. Before the unit operation, remove the protection foam and connect the cable of
the high water-level switch. Otherwise, the infrared humidifier will not work normally and may result in fire.
The detailed operation procedures are as follows:
1. Cut the cable tie and remove the protection foam fixed under the lamp, as shown in Figure 2-36 and Figure 2-37.
HWA cables
Protection foam is at the bottom of metal sheet
Protection foam is fitted below the reflector
Cable hole of high water-level test switch cable
Figure 2-36 Removing protection foam 1
switch cable
Pump
Lamp
灯管
High water-level test switch cable
保护泡沫
Protecti on foam
switch cable
Cable tie
Protecti on
保护泡沫
foam
Figure 2-37 Removing protection foam 2
2. Connect the cable of high water-level switch with the two HWA cables that through the cable hole of high water-level
test switch.
3. The floating pole and the infrared humidifier high water-level switch are tightly bound together with a rubber string
before delivery, as shown in Figure 2-38. Remove the rubber string before unit operation. Otherwise, the unit cannot
detect the high water-level alarm.
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34 Chapter 2 Mechanical Installation
Removing rubber string
Rubber string
Figure 2-38 Floating pole of high water-level switch
Removing pipe fasteners
To prevent the long copper pipes from scratching the metal plate and being damaged, the pipes are cushioned with
foam or bound up before delivery. Remove those materials before power-on commissioning.
2.8 Installation Inspection
After the mechanical installation is completed, you should check and confirm it according to Table 2-8.
Sufficient space is left around the unit for maintenance
The equipment is installed vertically and the installation fasteners have been fixed
The pipes between the indoor unit and outdoor unit have been connected, and the ball
valves of the indoor unit and outdoor unit have been opened completely
The condensate pump (if needed) has been installed
The drain pipe has been connected
The water supply pipe for the infrared humidifier has been connected
All pipe joints have been made correctly/tested
The transportation fasteners have been removed
Irrelevant things (such as transportation material, structure material and tools) inside or
around the equipment have been cleared after the equipment is installed
The air distribution system is installed as per room design (for example, raised
floor/grilles, ductwork, etc)
After confirming the preceding points, you can start the electrical installation.
Table 2-9 Installation Inspection
Items Results
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Chapter 3 Electrical Installation
This chapter introduces the electrical installation of the Liebert.PEX series air conditioner, including work introduction
and installation notes, wiring of indoor unit, wiring of outdoor unit and installation inspection.
3.1 Work Introduction And Installation Notes
Wires to connect at site
1. Power cable and control cable of indoor unit.
2. Solenoid valve of pipe extension kit (field installed option).
3. Outdoor unit (air-cooled series): signal control cable and power cable.
4. Input and output control cables of the unit.
Installation notes
1. The connection of all power cables, control cables and ground cables should comply with the local and national
electrician regulations.
2. See the unit nameplate for the full load current. The cable sizes should meet the local wiring rules.
3. Mains supply requirement: 400Vac, 50Hz.
4. The electrical installation must be performed by qualified professional installation personnel.
5. Before the wiring, use a voltmeter to measure the power supply voltage and make sure that the power supply has
been switched off.
Chapter 3 Electrical Installation 35
3.2 Wiring Of Indoor Unit
3.2.1 Locating Electrical Interface Of Indoor Unit
Open the front door of the indoor unit to reveal the interfaces of the electrical control box, as shown in Figure 3-1,
Figure 3-2 and Figure 3-3.
Field connection terminal block
Figure 3-1 Electrical control box interfaces of one-bay unit
Power
supply
connection
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36 Chapter 3 Electrical Installation
Power
supply
connection
Field connection terminal block
Figure 3-2 Electrical control box interfaces of two-bay unit
Note
The two-bay series with single compressor has only one compressor MCB and a contactor.
Field connection terminal block
Figure 3-3 Electrical control box interfaces of three-bay unit
3.2.2 Connecting Power Cable Of Indoor Unit
The power interfaces are located as shown in Figure 3-1, Figure 3-2 and Figure 3-3. The amplified figure of the power
interface is shown in Figure 3-4. Connect terminals L1 ~ L3, N, and PE to their counterparts of external power supply.
Fix the input cables to the cable clamp, note that the cable clamp is located on the inner side panel of the unit, see
Figure 3-5 for its position. For the cable specification, see the rated full load ampere (FLA) listed in Table 3-1.
Power
supply
connection
Figure 3-4 Amplified figure of main input isolation switch and
terminals
Note
The cable sizes should meet the local wiring regulations.
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Cable clamp
Figure 3-5 Cable clamp
Page 42
Chapter 3 Electrical Installation 37
Table 3-1 Rated full load ampere (FLA) (unit: A)
Standard model with
Model Standard model
P1020 24 33.1 24 33.1 21 14.9
P1025 26.1 35.2 26.1 35.2 23.1 17
P1030 33.1 42.2 33.1 42.2 30.1 24
P1035 35 44.1 35 44.1 32 25.9
P2035 42.6 56.2 42.6 56.2 41.2 29
P2040 42 47 33.4 47 42 29.8
P2045 48.4 62 48.4 62 47 34.8
P2050 46.2 49.1 35.5 49.1 46.2 34
P2055 53.4 67 53.4 67 52 39.8
P2060 60.2 60.2 48 57.9 60.2 48
P2070 64 64 51.8 59.8 64 51.8
P3070 65.3 70.3 53.1 70.3 65.3 53.1
P3080 71.1 73.2 58.9 73.2 71.1 58.9
P3090 82.3 81.5 70.1 82.3 82.3 70.1
P3100 92.3 92.3 80.1 86.5 92.3 80.1
Note:
The standard model is configured with the humidifier and the level 1 electric heating. Air-cooled unit FLA excludes the current
of the outdoor unit
level 2 electric
heating
No humidifying,
level 1 electrical
heating
No humidifying,
level 2 electric
heating
Humidifying
without heating
No humidifying or
heating
3.2.3 Connecting Control Cables
The field connection terminals are located as shown in Figure 3-1, Figure 3-2 and Figure 3-3. The amplified figure is
shown in Figure 3-6. The upper part of the terminal block is connected to the unit, while the lower part serves as user
control signal interfaces.
There is a shorting line respectively between
37# and 38#, between 37B# and 38B#, and
between 37C# and 38C#. Remove the shorting
line if the remote shut down signal is conneced
50#, 51# and 55# are custom alarm
terminals and 24# is their common terminal
Connecting
common alarm
terminal
Figure 3-6 Field connection terminals
Connecting smoke
sensor and 91# is
the common terminal
External alarm output
of the smoke sensor
Note
The connection personnel must take anti-static measures before connecting the control cables.
Water-under-floor sensor
Each unit is equipped with one water-under-floor sensor. You should connect one end of the sensor to terminal 51#,
and the other end to the common terminal 24#.
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38 Chapter 3 Electrical Installation
The number of the sensors in parallel connection is not limited, but each unit has only one water-under-floor alarm.
Remote shutdown
Three remote shutdown interfaces are provided in the unit and they are shorted in the factory.
Remove the shorting line between 37# and 38# and connect them to the first remote shutdown switch.
Remove the shorting line between 37B# and 38B# and connect them to the second remote shutdown switch.
Remove the shorting line between 37C# and 38C# and connect them to the third remote shutdown switch.
Smoke detecting
Terminals 91#, 92# and 93# can be connected to the optional smoke sensor. The terminal 91# is a common terminal,
the terminal 92# is a normally open (NO) contact and the terminal 93# is a normally closed (NC) contact. You can
select NO or NC contact according to the configured smoke sensor logic.
Terminals 80# and 81# are used to connect the external alarm output of the smoke sensor.
Control signals of outdoor unit
Terminals 70 & 71 and terminals 70A & 71A are two pairs of control signal input terminals of the outdoor unit. Their on
and off state is the same as that of the compressor.
Customized alarm
Terminals 50#, 51# and 55# can be connected to three kinds of sensors, including smoke sensor and
water-under-floor sensor. Terminal 24# is their common terminal. After the customized terminals are connected with
external alarm signals, you should set the corresponding customized alarm through the iCOM controller. See 5.7.6
SET ALARMS for details.
When the contact is open and no external alarm is generated, the input state of the customized terminal is open. But
when the contact is closed and the external alarm is generated, the input state of the customized terminal will be
shorted. At this point, the air conditioner system will generate an audible alarm, and the LCD of the iCOM controller will
display the alarm information.
The terminals can be defined as follows:
Terminals 50# and 24#: remote alarm.
Terminals 51# and 24#: water-under-floor sensor (in factory).
Terminals 55# and 24#: safe switch for condensate pump (optional).
External common alarm
Terminals 75# and 76# can be connected to the external common alarms. They are controlled by the external alarm
relay K3 on the circuit board. They output signals to external alarm devices, such as alarm indicator. When critical
alarm occurs, the contact will be closed to trigger remote alarms, send signals to the building management system or
dial the paging system automatically. The power supply of the external common alarm system is user-prepared.
For the detailed definition of other terminals, refer to Appendix 2 Circuit Diagram.
3.2.4 Connecting Solenoid Valve Of Pipe Extension Kit (Options, For Site Installation)
The solenoid valve of the pipe extension kit has two connection cables. The two cables are control cables, which are
used to connect with the corresponding terminals of the control board. Note that the solenoid valve cables of 1#
system and 2# system in double system unit should be remarked separately to avoid wrong connection. For detailed
connection terminals, refer to LLSV1 and LLSV2 connection terminal No. in Appendix 2 Circuit Diagram.
3.3 Wiring Of Outdoor Unit (For Air-Cooled Series)
3.3.1 Connecting Control Signal Cables Of Outdoor Unit
Open the sealed panel of the electric control box reveals the fan speed controller board (board for short), according to
the cable connection instructions in Liebert.PEX Condenser User Manual.
When a condenser with single system is used to match an indoor unit with single system, the digital signal of dry
contact J6 on the board (see 3.1 Work Introduction And Installation Notes) is connected with the control terminals
70#/71# (see Figure 3-6) of the indoor unit.
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When two condensers with single system are used to match an indoor unit with double system, the digital signals of
dry contacts J6 on the board corresponding to compressor systems 1# and 2# are respectively connected with the
control terminals 70#/71# and 70A#/71A# of the indoor unit.
When a condenser with double system is used to match an indoor unit with double system, you should short the
terminals 70# & 70A# and 71# & 71A#. The digital signal of dry contact J6 on the board can be connected with the
control terminals 70#/71# or 70A#/71A#.
For the detailed connection, refer to Appendix 2 Circuit Diagram.
3.3.2 Connecting Power Cables Of Outdoor Unit
The power cables of the outdoor unit are connected with the miniature circuit breakers (MCBs) reserved in the indoor
unit (see Figure 4-1, Figure 4-2 and Figure 4-3).
3.4 Installation Inspection
After the electrical installation is completed, you should confirm it according to Table 3-2.
Table 3-2 Installation Inspection
Items Results
The power supply voltage meets the rated voltage on the unit nameplate
The system electric loop has no open circuit or short circuit
Power cables and ground cables to the circuit breakers, indoor unit and
outdoor unit are well connected
The ratings of the circuit breakers and fuses are correct
The control cables are well connected
All the cables connections are fastened, with no loose screws
After confirming the preceding points, you can start the commissioning.
Chapter 3 Electrical Installation 39
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40 Chapter 4 System Power-On Commissioning
Chapter 4 System Power-On Commissioning
This chapter introduces the system power-on commissioning, including location of MCBs, and power-on
commissioning of air-cooled series unit and water-cooled series unit.
4.1 Location Of MCBs
The MCBs are located as shown in Figure 4-1, Figure 4-2 and Figure 4-3. The numbers in Figure 4-1 ~ Figure 4-3
have the following definitions:
1: Compressor MCB 3: Electric heater MCB 5: Condenser MCB 7: Control board MCB
2: Fan MCB 4: Infrared humidifier MCB 6: Compressor crankcase
heater MCB
1234567
Figure 4-1 MCBs location of one-bay unit
Figure 4-2 MCBs location of two-bay unit
Note
The two-bay series with single system has only one compressor MCB and a compressor contactor.
1234567
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Chapter 4 System Power-On Commissioning 41
Figure 4-3 MCBs location of three-bay unit
4.2 Power-On Commissioning Of Air-Cooled Series
4.2.1 Preparation Before Commissioning
Mechanical part
1. The protection materials for transportation have been removed. Check that the motor pulley and the fan pulley of the
FC fan model are fixed, the motor bearing and fan bearing are parallel, the belt is perpendicular to the two bearings
and the tension of the belt is correct. For the upflow unit, especially note that the transportation fixing bolts of the fan
have been removed. For the downflow unit of EC fan, make sure that that fan has been lowered into position, no
foreign matter inside the air channel, and the protective guards are installed correctly.
2. The cooling pipe system has passed the pressure leakage test.
3. The total charge quantity has been roughly calculated. If the charge exceeds the base charge allowed, additional
refrigerant oil should have been added into the system.
4. The water supply and drain pipes of the humidification system have been connected, the material requirement is
met and the leakage detection has been installed.
5. The crankcase heater of the compressor has been preheated for over 12hr.
6. The chilled water system has passed the pressure leakage test, and is qualified.
7. The chilled water system has been cleaned and discharged (air bleed valve is on top of the cooling coil header).
8. The chilled water system has been confirmed ready for operation.
9. The equipment room is above 20°C with certain heat load. Otherwise, pre-heat the equipment room with any
heating device, or by manual running the heaters of the unit (in this case, go through the following procedures till the
third entry of 4.2.2 Commissioning Procedures first) and of other equipment in the room. Ensure sufficient heat load
for the commissioning.
10. During low ambient conditions, it may be necessary to manually raise the condensing pressure up to 16bar by
manually shielding some condensing area to limit condensing air volume.
Electric part
1234567
1. Check that the voltage of the main power supply is within ±10% of the rating, and the isolation switch of the
air-cooled condenser of the outdoor unit has been closed.
2. Check that all power and control circuits are properly connected. Fasten all connection connectors.
3. Separate any power cables and the low voltage control cables from each other.
4. Check that the transportation foam block of the infrared humidifier has been removed, and the high water level
cables have been connected and its float mechanism operates correctly.
5. Check the phase sequence:
1) For the FC fan model, the phase sequences of all three-phase devices have been adjusted consistent before
delivery. During commissioning, you only need to ensure that the phase sequence of a random three-phase device is
correct. In step two of 4.2.2 Commissioning Procedures, if you run the fan by clicking on the fan contactor in the
electric control box with a
the phase sequence is wrong, exchange any two phases of the L line of the power supply.
straight screwdriver, you can judge the phase sequence by observing the wind direction. If
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42 Chapter 4 System Power-On Commissioning
2) For the EC fan model, the fan itself does not require phase sequence; therefore, the phase sequence needs to be
checked through compressor. After step five static charging refrigerant of 4.2.2 Commissioning Proc edures is
completed, you should first close the connection pipe in the pressure gauge with the refrigerant filling tank, and then
use the straight screwdriver to press, so as to make one compressor contactor in the electric control box contact in
short time and start the compressor. Determine the system phase sequence through observing the high/low value in
pressure gauge that connected to the system, if the system is unable to quickly build high and low pressure, it means
the phase sequence is wrong, you should exchange any two phases of the L line of the power supply.
4.2.2 Commissioning Procedures
1. Switch off the MCBs of all components. Switch on the main isolation switch and control board MCBs. Check that the
control voltage is 24Vac±10%.
2. Switch on the fan MCB. Press the fan contactor to start the fan and make sure the fan blowing direction is correct.
Start the unit and measure all the operation phase currents of the fan.
3. Switch on the electric heater MCB and change the temperature setpoint to start the electric heater, or start it
manually. Measure all the operation phase currents of the electric heater.
To trigger the electric heater, you should:
Enter the ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘TEMP SET’ to adjust the temperature setting value to ‘T
= T
temp
return air temp
heater contactor will be closed and the LCD will display 100% output of the electric heater. Adjust the temperature
setting value to ‘T
indicates that the heating function is normal. Keep this temperature value and no heating requirement is needed. Then
continue with the following procedures.
+ 5, ‘T
setting temp
return air temp
’ (T
setting temp
’ is the present ambient temperature on the LCD). Wait for 1min, and the electric
= T
return air temp
setting temp
’ (T
setting
- 5). Wait for 1min, and then the electric heater will stop working. It
Note
Do not manually press the infrared humidifier contactor unless there is water in the humidifier pan.
4. Switch on the infrared humidifier MCB and change the humidity setpoint to start the infrared humidifier, or start it
manually. Measure all the operation phase currents of the infrared humidifier. In addition, inject water manually to
check that the charging pipe and drain pipe do not leak, and that the drain pipe is clear.
To trigger the infrared humidifier, you should:
Enter the ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘HUM SET’ to adjust the humidity setting value to ‘T
T
ambient hum
+ 10%, ‘T
ambient hum
’ is the present ambient humidity on the LCD). Wait for 1min, and the humidifier contactor
setting hum
will be closed and the LCD will display 100% humidifying output. Adjust the temperature setting value to ‘T
(T
setting hum
= T
ambient hum
- 10%). Wait for 1min, and then the humidifier will stop working. It indicates that the humidifying
’ (T
setting hum
setting hum
=
’
function is normal. Keep this humidity value and no humidifier requirement is needed. Then continue with the following
procedures.
Note
After commissioning, restore the temperature and humidity setpoints to the default values or original setpoints.
5. Connect the compound pressure gauge to the corresponding high and low pressure schrader valves. Evacuate the
cooling system vacuum to -30in.Hg (pumping time: >3hr), and hold the state for 4hr. The pressure should not rise, and
the color of the sight glass is normal (to ensure the cooling system vacuum and dry effect, evacuate the cooling
system repeatedly at least three times).
After checking the vacuum state of the cooling system, charge with liquid refrigerant (usually charge until the
pressures inside the refrigerant container equalizes with that in the cooling system).
Connect the pressure gauge to the refrigerant cylinder.
Switch on the compressor MCB and condenser MCB.
1) Change the temperature setpoint to start cooling, or start cooling manually. Make sure that the dehumidification and
HGBP are in closed states. Measure all the operation phase currents of the compressor in real time.
To start cooling (start the compressor), you should:
Make sure that the unit chilled water is in closed state, and enter ‘SERVICE MENU’ -> ‘SETPOINTS’ to set S138 to
‘20K’.
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Chapter 4 System Power-On Commissioning 43
Enter ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘TEMP SET’ to adjust the temperature setting value to ‘T
= T
return air temp
- 5, ‘T
return air temp
’ is the present ambient temperature on the LCD). Wait for 1min, and the compressor
setting temp
’ (T
setting temp
contactor will be closed and the LCD will display 100% cooling requirement. After at least 3min operation, change the
temperature setting value to ‘T
return air temp
’ (T
setting temp
= T
return air temp
+ 5). Wait for 30s, and then the compressor will stop
working. It indicates that the cooling function is normal.
Note
After commissioning, restore the temperature setpoint to the default or original setpoint.
2) Check the operation current of the condenser fan, and check that the fan runs stably.
3) Start the compressor, and charge refrigerant gas (R22) or refrigerant liquid (R407C) slowly to the compressor inlet
until the subcooling degree reaches 8°C ~ 10°C and the sight glass is clear. The condensing temperature should be
kept at 45°C.
Keep charging and adjust the thermostatic expansion valve to 41°F ~ 46.4°F superheat degree. The adjustment step
of the valve should be smaller than 1/4 round, and the interval between two steps should be at least 15min.
Observe the compressor suction pipes and make sure that there is no water condensing on the surface of the
compressor and the pipes, so as to avoid the risk of liquid slugging the compressor.
At the condition of 22°C/50% return air state and 16bar ~ 17bar condensing pressure, the compressor suction
pressure should be above 5bar.
At the condition of 24°C/50% return air state and 16br ~ 17br condensing pressure, the compressor suction pressure
should be above 5.5bar.
4) Check the dehumidification function
To trigger dehumidification, you should:
Change the humidify setting (see 5.7 SERVICE MENUS) to 10% lower than the indoor RH. The control system
should then trigger the call for dehumidification, the dehumidification solenoid valve switches on the dehumidification
indicator Q3 on the control board turns on. Then change the humidity setting higher than the indoor RH. If the
dehumidification solenoid valve of the FC fan unit switches off, and the airflow of the EC fan unit drops while the
dehumidification indicator Q3 turns off, it means the dehumidification function is normal. Note that during the
commissioning process, if the indoor temperature is 3°C higher than the temperature setting, the system may enter the
forced cooling mode, and the dehumidification demand will not be responded.
6. Commission the chilled water function: Make sure that the chilled water source is supplied normally. The
temperature of the chilled water ranges from 7.6°C to 9°C. Set the temperature point to trigger FC demand, and the
chilled water valve is opened.
To trigger the chilled water demand, you should:
Enter ‘SERVICE MENUS’ -> ‘SETPOINTS’ to set S138 to ‘8K’. Enter the ‘SERVICE MENUS’ -> ‘SETPOINTS’ to set
S138 to ‘8K; enter ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘HUM SET’ to adjust the humidity setting value to ‘T
(T
setting hum
T
return air temp
= T
ambient hum
) and then enter ‘TEMP SET’ to adjust the temperature setting value ‘T
setting temp
’ (T
setting temp
-2). Wait for 30s, and the FC requirement will be triggered and the chilled water valve will be open.
setting hum
’
=
Note
After commissioning, restore the temperature setpoint to the default or original setpoint.
4.2.3 Inspection After Commissioning
After commissioning, check and confirm it according to Table 4-1.
Items Results
Check that all output functions are automatic
Check that the temperature & humidity setpoints and control
precisions are set correctly
Check that other functions are set correctly
Liebert.PEX2 Series Air Conditioner User Manual
Table 4-1 Inspection after commissioning
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44 Chapter 4 System Power-On Commissioning
4.3 Power-On Commissioning Of Water-Cooled Series
4.3.1 Preparation Before Commissioning
Mechanical and system part
1. The protection materials for transportation have been removed. Check that the motor pulley and the fan pulley of the
FC fan model are fixed, the motor bearing and fan bearing are parallel, the belt is perpendicular to the two bearings
and the tension of the belt is correct. For the upflow unit, especially note that the transportation fixing bolts of the fan
have been removed. For the downflow unit of EC fan, make sure that that fan has been lowered into position, no
foreign matter inside the air channel, and the protective guards are installed correctly.
2. The pressure test and leakage test of the cooling water system have been completed.
3. The cooling water system has been cleaned and drained.
4. The cooling water system has been confirmed ready for operation.
5. The chilled water system has past the pressure leakage test, and is qualified.
6. The chilled water system has been cleaned and discharged (air valve is on top of the heater exchanger pipe coil).
7. The chilled water system has been confirmed ready for operation.
8. The water supply and drain pipes of the humidification system have been reliably connected, the material
requirement is met and the leak detection has been done. 9. The compressor crankcase heater has been preheated
for over 12hr.
10. The equipment room temperature is above 68°F with sufficient heat load. If the heat load is insufficient, heat the
equipment room with heating devices, or by manually running other heat generating equipment to make sure that the
heat load is sufficient for the commissioning.
Electric part
1. Check that the voltage of the main power supply is within ±10% of the rating, and the isolation switch of the
air-cooled condenser of the outdoor unit has been closed.
2. Check that all the power and control cables are properly connected. Fasten all the electric and control connection
connectors.
3. Lay the power cables and the control cables away from each other.
4. Check that the transportation foam block of the infrared humidifier has been removed, and the high water level
cables have been connected and its float mechanism operates correctly.
5. Check the phase sequence:
1) For the FC fan model, the phase sequences of all three-phase devices have been adjusted consistent before
delivery. During commissioning, you only need to ensure that the phase sequence of a random three-phase device is
correct. In step three of 4.2.2 Commissioning Procedures, if you run the fan by clicking on the fan contactor in the
electric control box with a straight screwdriver, you can judge the phase sequence by observing the wind direction. If
the phase sequence is wrong, exchange any two phases of the L line of the power supply.
2) For the EC fan model, the fan itself does not require phase sequence; therefore, the phase sequence needs to be
checked through compressor. After the step six static charging refrigerant of 4.2.2 Commissioning Procedures is
completed, you should first close the connection pipe in the pressure gauge with the refrigerant filling tank, and then
use the straight screwdriver to press, so as to make one compressor contactor in the electric control box contact in
short time and start the compressor. Determine the system phase sequence through observing the high and low value
in pressure gauge that connected to the system, if the system is unable to quickly build high and low pressure, it
means the phase sequence is wrong, you should exchange any two phases of the L line of the power supply.
4.3.2 Commissioning Procedures
1. Switch off the MCBs of various components. Switch on the main isolation switch and control board MCBs. Check
the control voltage.
2. Check that the motor pulley and the fan pulley are fixed, the motor bearing and fan bearing are parallel, the belt is
perpendicular to the two bearings and the tension of the belt is proper.
3. Switch on the fan MCB and click on the contactor of the indoor fan to confirm the fan blowing direction is correct.
Start the unit and measure all the operation phase currents of the fan.
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Chapter 4 System Power-On Commissioning 45
4. Switch on the electric heater MCB and change the temperature setpoint to start the electric heater, or start it
manually. Measure all the operation phase currents of the electric heater.
To trigger the electric heater, you should:
Enter the ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘TEMP SET’ to adjust the temperature setting value to ‘T
temp
= T
return air temp
+ 5, ‘T
return air temp
’ is the present ambient temperature on the LCD). Wait for 1min, and the electric
setting temp
’ (T
setting
heater contactor will be closed and the LCD will display 100% output of the electric heater. Adjust the temperature
setting value to ‘T
setting temp
’ (T
setting temp
= T
return air temp
- 5). Wait for 1min, and then the electric heater will stop working. It
indicates that the heating function is normal. Keep this temperature value and no heating requirement is needed. Then
continue with the following procedures.
Note
After commissioning, restore the temperature setpoint to the default or original setpoint.
5. Switch on the infrared humidifier MCB and change the humidity setpoint to start the infrared humidifier, or start it
manually. Measure all the operation phase currents of the infrared humidifier. Manually inject water inlet to the cooling
system to check that the charging pipe and drain pipe do not leak and that the drain pipe is clear.
To trigger the infrared humidifier, you should:
To trigger the humidifier, you should:
Enter the ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘HUM SET’ to adjust the humidity setting value to ‘T
T
ambient hum
+ 10%, ‘T
ambient hum
’ is the present ambient humidity on the LCD). Wait for 1min, and the electric heater
setting hum
’ (T
setting hum
=
contactor will be closed and the LCD will display 100% humidifying output. Adjust the temperature setting value to
‘T
setting hum
’ (T
setting hum
= T
ambient hum
- 10%). Wait for 1min, and then the humidifier will stop working. It indicates that the
humidifying function is normal. Keep this humidity value and no heating requirement is needed. Then continue with the
following procedures.
Note
After commissioning, restore the humidity setpoint to the default or original setpoint.
6. Make sure that the chilled water source is supplied normally. Change the temperature setpoint to start cooling, or
start cooling manually. Measure all the operation phase currents of the compressor in real time. Check the
condensation subcooling degree, suction superheating and air bulbs of the sight glass to make sure that the
compressor works normally, and add refrigerant if necessary.
To start cooling (start the compressor), you should:
Make sure that the unit chilled water is in closed state, and enter ‘SERVICE MENU’ -> ‘SETPOINTS’ to set S138 to
‘20K’.
Enter ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘TEMP SET’ to adjust the temperature setting value to ‘T
= T
return air temp
- 5, ‘T
return air temp
’ is the present ambient temperature on the LCD). Wait for 1min, and the compressor
setting temp
’ (T
setting temp
contactor will be closed and the LCD will display 100% cooling requirement. After at least 3min of running, change the
temperature setting value to ‘T
return air temp
’ (T
setting temp
= T
return air temp
+ 5). Wait for 30s, and then the compressor will stop
working. It indicates that the cooling function is normal.
Note
After commissioning, restore the temperature setpoint to the default or original setpoint.
7 Check the dehumidification function
To trigger dehumidification, you should:
Change the humidify setting (see 5.7 SERVICE MENUS) to 10% lower than the indoor RH. The control system
should then trigger the call for dehumidification, the dehumidification solenoid valve switches on, and the
dehumidification indicator Q3 on the control board turns on. Then change the humidity setting higher than the indoor
RH. If the dehumidification solenoid valve switches off, and the dehumidification indicator Q3 turns off, it means the
dehumidification function is normal. Note that during the commissioning process, if the indoor temperature is 37.4°F
higher than the temperature setting, the system may enter the forced cooling mode, and the dehumidification demand
will not be responded.
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46 Chapter 4 System Power-On Commissioning
8. Commission the FC function: Make sure that the chilled water source is supplied normally. The temperature of the
chilled water ranges from 45.6°F to 48.2°F. Set the temperature point to trigger FC demand, and the chilled water
valve is opened.
To trigger FC demand, you should:
Enter the ‘SERVICE MENUS’ -> ‘SETPOINTS’ to set S138 to ‘8K; enter ‘USER MENUS’ -> ‘SETPOINTS’ -> ‘HUM
SET’ to adjust the humidity setting value to ‘T
temperature setting value ‘T
setting temp
’ (T
setting hum
setting temp
triggered and the chilled water valve will be open.
Note
After commissioning, restore the temperature setpoint to the default or original setpoint.
4.3.3 Inspection After Commissioning
After commissioning, check and confirm it according to Table 4-2.
Table 4-2 Inspection after commissioning
Items Results
Check that all output functions are automatic
Check that the temperature & humidity setpoints and control
precisions are set correctly
Check that other functions are set correctly
= T
’ (T
setting hum
return air temp
= T
ambient hum
) and then enter ‘TEMP SET’ to adjust the
-2). Wait for 30s, and the FC requirement will be
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Chapter 5 iCOM Controller
The iCOM controller uses menu operation. It can monitor, display and operate the precision cooling air conditioner and
control the environment within a set range. This chapter expounds the LCD, button and indicator panel, structure chart
of control menu, startup interface, main interface, USER MENUS, SERVICE MENUS, ADVANCED MENUS and
EVENT NAME AND DIFINITION of the iCOM controller.
5.1 LCD
An LCD is located on the front panel of the Liebert.PEX series air conditioner. The LCD can display the current state of
the equipment room, such as temperature and humidity, and so on. You can also read and modify the equipment
configuration through the LCD.
The LCD uses blue backlight. If no button is pressed within a certain period of time (settable; default: 5min), the
backlight will be off, until the next time any button is pressed.
5.2 Button And Indicator Panel
Nine buttons and two indicators are located on the button and indicator panel, including:
z Indicators: alarm indicator and operation indicator.
z Buttons: ON/OFF button, enter button, ESC button, up button, down button, left button, right button, alarm silence
button and help button.
The button and indicator panel is shown in Figure 5-1.
Chapter 5 iCOM Controller 47
Alarm silence button
Alarm indicator
ON/OFF button
Operation indicator
Figure 5-1 Button and indicator panel
ESC
button
Left button
Help
button
Up button
Down
button
Enter button
Right button
The indicators are described in Table 5-1.
Table 5-1 Indicator description
Indicator Description
Alarm indicator The alarm indicator turns on in red upon alarms. It is off after the alarm is cleared
Operation indicator
The operation indicator is on in green when the unit is operating. When the unit is shut down, it will be
on in yellow
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48 Chapter 5 iCOM Controller
The functions of the buttons are described in Table 5-2.
Button Function description
1. Switch on/off the system.
Press the ON/OFF button to shut down an operating system, or to start an idle system.
ON/OFF
button
Enter button
ESC button
Up button
Down button
Left button
Right button
Alarm
silence
button
Help button
2. Test the display state of the backlight of the LCD and the operation indicator.
After powering-on, when the system is in the standby state (defined as test state in this manual), pressing the
ON/OFF button will switch between the operation indicator (green then) and the LCD backlight. This function is
used to test whether the LCD backlight and the operation indicator are normal
1. Enter the selected menu, or save the setting after parameters are changed. When you are entering a menu or
changing a parameter, the menu and the parameter will be high lighted.
2. Test the display of characters.
When the system is in the test state, pressing the enter button will display the ASCII code. This function is used to
test whether the characters are displayed normally on the LCD
1. Quit the current menu.
2. Abolish the current change of parameter.
3. Test the LCD high light.
Pressing the ESC button to switch the LCD between light and high light when the system is in the test state. This
function can test whether the LCD high light is normal
1. Increase the value of the displayed parameter during parameter setting.
2. Scroll a row or a screen up in the query state.
3. Test the buzzer.
Pressing the up button when the system is in the test state will increase the buzzing frequency (initial value: 0%).
Meanwhile the buzzer will sound at the set frequency. This function is used to test whether the buzzer is normal
1. Decrease the value of the displayed parameter during parameter setting.
2. Scroll a row or a screen down in the query state.
3. Test the buzzer.
If the buzzer frequency is not 0%, pressing the down button when the system is in the test state will decrease the
buzzing frequency. Meanwhile the buzzer will sound at the set frequency. This function is used to test whether the
buzzer is normal
1. Select the left bit during the parameter setting operation.
2. Test the LCD contrast.
Pressing the left button when the system is in the test state will decrease the LCD contrast (by default: 100%). This
function is used to test whether the LCD contrast is normal
1. Select the right bit during the parameter setting operation.
2. Test the LCD contrast.
If the LCD contrast is not 100%, pressing the right button when the system is in the test state will increase the LCD
contrast. This function is used to test whether the LCD contrast is normal
1. The system will issue an alarm sound upon alarms. If you press the alarm silence button, the alarm sound will
be eliminated.
2. Clear the current alarm after the alarm sound is silenced.
3. Test the alarm indicator, and rest the LCD contrast and buzzer frequency.
Pressing the alarm silence button when the system is in the test state will switch the alarm indicator between on
and off. It can test whether the alarm indicator is normal. Meanwhile, reset the LCD contrast to 100% and buzzer
frequency to 0%
1. Display the online help.
2. Test the yellow display of the LCD operation indicator.
When the system is in the test state, pressing the help button will switch on and off the LCD operation indicator.
This function is used to test whether the yellow display of the LCD operation indicator is normal
Note
1. After the system is powered on, the system will assume the operation state before power-off. For example, if the system is in
the work state when it is powered off, it will enter the work state automatically after power-on. You do not need to start it
manually.
2. When the system is in the test state, the setpoints will not be written into the iCOM controller.
Table 5-2 Function description of buttons
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5.3 Structure Chart Of Control Menu
Please refer to Appendix 3 Menu Structure Of iCOM Controller.
5.4 Startup Interface
After the system is powered on, it is in the waiting state. The LCD will display the interface shown in Figure 5-2.
Figure 5-2 Startup interface
5.5 Main Interface
After power-on, the LCD will enter the main interface after 20s. The main interface provides the general information of
the relative equipment status, including current temperature and humidity, temperature and humidity setpoints,
equipment output status (fan, compressor, cooling, heating, dehumidifying, humidifying), alarm and maintenance
status.
The main interface has two display modes: graphical and simple. The difference between the two display modes is
that the graphic interface (see Figure 5-3) displays the percentage output chart of the function components while the
simple interface (see Figure 5-4) displays the icons of current operation mode only. The switching of two modes can
be realized by operating the menu. For details, refer to 5.6.7 DISPLAY SETUP. The upper left corner of the main
interface displays the current unit number; the upper right corner displays the current system status. If there is no
button operation for 255s on other menu display screen, the LCD screen will return to the main interface.
Chapter 5 iCOM Controller 49
UNIT 1
20℃ 42％
32℃
100 ％
100 ％
0％
Figure 5-3 Graphical mode of main interface
UNIT
Figure 5-4 Simple mode of main interface
1
20 ℃ 42％
32 ℃ 43％
SYS ON
43％
SYS ON
RCT
0％
0％
0％
0％
RCT
Setting value
Setpoint
Present value
Setpoint
S etting value
Present value
The icons of the graphical mode and the simple mode on the main interface are defined in Table 5-3.
Table 5-3 Definition of icons
Icon Definition Icon Definition
Fan running
Cooling
Hot water heating
Electric heating
Free cooling
Maintenance
Dehumidifying
Humidifying
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50 Chapter 5 iCOM Controller
5.6 USER MENUS
Press the enter or down button on the main interface to enter the USER MENUS, as shown in Figure 5-5. The USER
MENUS are displayed in six pages, each displaying one or two submenus. Press the enter button to highlight the
submenu, the up or down button to browse the submenus, and the enter button to enter the selected one.
USER MENUS
PASSWORD LEVEL
C / F
H%R
SET
USER MENUS
SET
5.6.1 PASSWORD
The password is necessary for some setpoints. After inputting the password (user password: 149), use the up button
and down button to browse all the options, and then press the enter button to enter the selected one.
5.6.2 SETPOINTS
The setpoints will not be lost when the power fails. You can enter to browse and set the parameters in the SETPOINTS
submenu through the USER MENUS. The left row displays the parameter codes; the middle row, the parameter name;
the right row, the setpoints, as shown in Table 5-4.
Parameters Default Setting range Description
U102 TEMP SET 23°C 5°C ~ 40°C Temperature setpoint
U103 HUM SET 50% 1% ~ 80% Humidity setpoint
U104 HUM CTRL Rel
U105 SUP SENS No No, Lim, Ctrl, Cool Supply air type
U106 SUP TEMP 15°C 5°C ~ 25°C Air temperature limit setpoint
U107 BACK TSP 15°C 5°C ~ 40°C Backup temperature setpoints
If you want to modify the preceding setpoints, you should input the password before entering the SETPOINTS menu.
Then press the enter button to highlight it and use the up and down button to scroll the options. Press the enter button
to select one parameter, use the up or down button to set the value, and press the enter button to save the change.
1 / 6
0
?
SETPOINTS
4 / 6
SENSOR DATA
DISPLAY SETUP
Table 5-4 Descriptions of SETPOINTS parameters
USER MENUS
EVENT
???
LOG
EVENT LOG
GRAPHICS
USER MENUS
TOTAL RUN HRS
SLEEP MOOE
Figure 5-5 USER MENUS
Pred (predictive), Comp
(compensable), Rel (relative)
2 / 6
5 / 6
SET
ALARMS
SET ALARMS
USER MENUS
SERUICE INFO
ACTIVE
ALARMS
Humidity control type
ACTIVE ALARMS
3 / 6USER MENUS
6 / 6
5.6.3 EVENT LOG
You can enter the EVENT LOG menu without a password, as shown in Figure 5-6.
0EVENT LOG P
01
（01）1/31/2007 10 00
:
Warning
Power loss
Figure 5-6 EVENT LOG menu
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The EVENT LOG menu saves the last 400 system records. The event types include message, warning and alarm.
z When the event type is message, the LCD will display the event name only.
z When the event type is warning, the LCD will display the event name and the alarm indicator will turn on in red.
z When the event type is alarm, the LCD will display the event name, the alarm indicator will turn on in red, and an
audible alarm will be raised.
5.6.4 GRAPHICS
The GRAPHICS menu provides two kinds of graphs: RETURN TEMP and RETURN HUMIDITY. These graphs reflect
the temperature and humidity changes over a period of time in the past.
In the graphs, the current temperature or humidity is the origin, the time is the horizontal axis, and the temperature or
humidity is the vertical axis, as shown in Figure 5-7.
Chapter 5 iCOM Controller 51
RETURN TEMP
:
Figure 5-7 The graph of return temperature and return humidity
10 40t8d
01
+03
C
27
°
-03
:
RETURN HUMIDITY
::
10 42t8d
01
+20
+55%
-20
As the horizontal axis, the time range can be set into eight kinds. Each pixel indicates different time in different time
ranges. See Table 5-5 for the detailed time range.
Table 5-5 Time range
Time range Time indicated by each pixel Time range Time indicated by each pixel
8min 6s 2d 36min
32min 24s 4d 72min
1hr 45s 8d 144min
12hr 9min 16d 288min
24hr 18min
The scaling of the vertical axis can also be set. For the RETURN TEMP, the scaling range is ±3 ~ ±20; for the
RETURN HUMIDITY, the scaling range is ±10 ~ ±30. The bigger the scaling range is, the bigger the value each pixel
indicates will be, and the more centered the curves will be.
You can set the parameters without inputting the password. Press the enter button to highlight the parameters, use the
up or down button to select one parameter. Then press the enter button again to enter the parameter, and use the up
or down button to set the value. Press the enter button to save the change at last.
5.6.5 SET ALARMS
The SET ALARMS menu is used to set the upper and lower limits of temperature and humidity alarms. The settings
will not be lost when the power fails. You can select the ‘SET ALARMS’ submenu to browse and set the parameters
through the USER MENUS. The parameters are described in Table 5-6.
Note
It is recommended not to change the system defaults. If you consider it necessary to change the defaults, consult professionals
first and set the alarm settings under the guidance of them.
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52 Chapter 5 iCOM Controller
Parameters Default Setting range Description
U202 RTN SNSR Yes Yes, No Return air alarm enable
U203 HI TEMP 27°C 1°C ~ 99°C High return air temperature alarm setpoint
U204 LO TEMP 18°C 1°C ~ 99°C Low return air temperature alarm setpoint
U205 HI HUM 60% 1% ~ 99% High return air humidity alarm setpoint
U206 LOW HUM 40% 1% ~ 99% Low return air humidity alarm setpoint
U207 SENSOR A No Yes, No Sensor A alarm enable
U208 HI TEMPA 50°C 1°C ~ 99°C High temperature alarm setpoint of sensor A
U209 LO TEMPA 25°C 1°C ~ 99°C Low temperature alarm setpoint of sensor A
U210 HI HUM A 70% 1% ~ 99% High humidity alarm setpoint of sensor A
U211 LO HUM A 30% 1% ~ 99% Low humidity alarm setpoint of sensor A
U213 SUP SNSR No Yes, No Supply air alarm enable
U214 HI SUP T 24°C 1°C ~ 99°C High supply air temperature alarm setting value
U215 LO SUP T 10°C 1°C ~ 99°C Low supply air temperature alarm setting value
To browse through the menu, press the enter button to highlight the option, and use the up or down button to scroll.
Password is required for changing the setpoints. Then, enter the SET ALARMS menu, press the enter button to
highlight the option, use the up or down button to browse the submenu. Press the enter button to enter the selected
parameter. Use the up or down button to change the setpoints, and press the enter button to save the change, or press
the ESC button to quit the change.
Table 5-6 Descriptions of SET ALARMS parameters
5.6.6 SENSOR DATA
You can monitor the data acquired by the sensors through the SENSOR DATA menu. The values are read only, no
setting or change is allowed. The parameters are described in Table 5-7.
Parameters Unit Description Parameters Unit Description
U301 TEMP A °C Temperature of sensor A U313 Hi Temp °C Daily high temperature
U302 HUM A %
U303 TEMP B °F Temperature of sensor B U314 Lo Te M m
U304 HUM B %
U305 TEMP C °C Temperature of sensor C U314 Lo Temp °C Daily low temperature
U306 HUM C %
U307 FC TEMP °C Free cooling temperature U315 Hi Hu M m Daily high humidity (minute)
U308 AMB TEMP °C Outdoor temperature U315 Hi Hu S s Daily high humidity (second)
U309 FC STATE - Free cooling status U315 Hi Humi % Daily high humidity
U310 DS1 TEMP °C
U311 DS2 TEMP °C
U313 Hi Te H hr
U313 Hi Te M m
U313 Hi Te S s
Table 5-7 Descriptions of SENSOR DATA parameters
Relative humidity of
sensor A
Relative humidity of
sensor B
Relative humidity of
sensor C
Temperature of digital
scroll 1
Temperature of digital
scroll 2
Daily high temperature
(hour)
Daily high temperature
(minute)
Daily high temperature
(second)
U314 Lo Te H h Daily low temperature (hour)
U314 Lo Te S s
U315 Hi Hu H h Daily high humidity (hour)
U316 Lo Hu H h Daily low humidity (hour)
U316 Lo Hu M m Daily low humidity (minute)
U316 Lo Hu S s Daily low humidity (second)
U316 Lo Humi % Daily low humidity
Daily low temperature
(minute)
Daily low temperature
(second)
5.6.7 DISPLAY SETUP
The DISPLAY SETUP menu is used to set the LCD display attributes. Password is not required for changing the
setpoints. The parameters are described in Table 5-8.
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Chapter 5 iCOM Controller 53
Table 5-8 Descriptions of DISPLAY SETUP parameters
Parameters Default Setting range Description
RUS, CZE, CHI,
U401 LANGUAG EN
U402 YEAR 2005 - Current year
U402 MONTH 04 01 ~ 12 Current month
U402 DAY 19 01 ~ 31 Current day
U403 HOUR 19h - Current hour
U403 MINUTE 8min - Current minute
U403 SECOND 17s - Current second
U404 TEMP F/C °C °F, °C Temperature indication
U405 CONTRAST 50% 0% ~ 100% Display contract
U406 BUZ FREQ 50% 0% ~ 100% Buzzer frequency. 0% means buzzer silenced
U406 BUZ TEST Off On, Off
U407 BACKLITE 5min
U408 SCREEN Graph
U409 SHOWS A + S SET, ACT, A + S
U410 DISPLAY Norm Norm (normal), Inv Display color
U411 DATE m/d/y m/d/y, d.m.y, y-m-d Date display format
ESP, FRE, ITA,
DEU, EN, POR
5min, 10min,
30min, 1hr, 12hr
Graph, Simple,
SimCo, GraCo
Language options
Buzzer frequency test switch. It determines whether or not there
will be sound accompanying the adjustment of BUZ FREQ
through the setting
Backlight time, or the backlight time when there is no button
operation
Main interface display mode
Main interface display mode of setpoints and actual values.
Range:
SET: only setpoints of the temperature and humidity are
displayed.
ACT: only actual temperature and humidity are displayed.
A + S: both setpoints and actual values of the temperature and
humidity are displayed
5.6.8 TOTAL RUN HRS
The TOTAL RUN HRS menu records the total run time (unit: hr) of the system components. You can also set the run
time limits of the system components through this menu. If the actual component run time exceeds the set limit, alarms
will be raised.
This menu requires password. You can reset the total run time to zero in order to restart timing.
Note
Resetting the timers is not needed unless the components are replaced.
The parameters on this menu are described in Table 5-9. Each component has a LIMIT option to set the run time limit
of the corresponding component.
Parameters Default Related component Parameters Default Related component
U502 MOTOR(S) 1000hr U507 EL HEAT1 34hr
U502 LIMIT 32000hr
U503 COMP1 500hr U508 EL HEAT2 45hr
U503 LIMIT 32000hr
U504 COMP2 500hr U509 EL HEAT3 0hr
U504 LIMIT 32000hr
U505 CW/FC 1000hr U510 HUM 7hr
U505 LIMIT 32000hr
U506 HG/HW 23hr U511 DEHUM 1hr
U506 LIMIT 32000hr
Table 5-9 Descriptions of TOTAL RUN HRS parameters
Fan motor
Compressor 1
Compressor 2
Chilled water/free
cooling
Hot gas/hot water
U507 LIMIT 32000hr
U508 LIMIT 32000hr
U509 LIMIT 32000hr
U510 LIMIT 32000hr
U511 LIMIT 32000hr
Electric heater 1
Electric heater 2
Electric heater 3
Humidifier
Dehumidification
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54 Chapter 5 iCOM Controller
5.6.9 SLEEP MODE
In the sleep mode, the air conditioner unit can realize auto-on/off. Through the SLEEP MODE menu, you can set two
time zones of the sleep mode, and select the sleep timing mode. The parameters on this menu are described in Table
5-10.
Parameters Default Setting range Description
U602 MON No
U602 TUE No
U602 WED No
U602 THU No
U602 FRI No
U602 SAT No
U602 SUN No
U605 START 1 0hr
U605 START 1 0m
U605 STOP 1 0hr
U605 STOP 1 0m
U607 START 2 0hr
U607 START 2 0m
U607 STOP 2 0hr
U607 STOP 2 0m
U609 TIME MOD Auto Auto, Yes, No
U610 TIME TYP S.OFF S.OFF, DEADB Timing mode selection
U611 DEADBAND K 2K ~ 15K Used to set the deadband temperature setting range
Table 5-10 Descriptions of SLEEP MODE parameters
Sleep mode day, including Monday ~ Sunday. Set the value of any
Yes, No
-
day to ‘Yes’, and the system will enter sleep mode on that day every
week. This parameter works together with the following hour and
minute settings to designate an exact time
Sleep mode start time 1. The first parameter is used to set the hour of
time, and the second one is used to set the minute of time
Sleep mode end time 1. The first parameter is used to set the hour of
time, and the second one is used to set the minute of time
Sleep mode start time 2. The first parameter is used to set the hour of
time, and the second one is used to set the minute of time
Sleep mode end time 2. The first parameter is used to set the hour of
time, and the second one is used to set the minute of time
Timing mode setting. Range:
Auto: during the system sleep time, if high/low temperature occurs, the
system will resume operation and mask the alarm for 15min. The
system will re-enter the sleep mode after the alarm is cleared
Yes: start sleep mode
No: no sleep mode
5.6.10 SERVICE INFO
The SERVICE INFO menu provides the contact information of customer service personnel. The information is read
only.
5.6.11 ACTIVE ALARMS
The ACTIVE ALARMS menu displays the active alarms of the system. No password is required to query this menu.
5.7 SERVICE MENUS
Press the right button at the first page of the USER MENUS, and you can enter the SERVICE MENUS, as shown in
Figure 5-8.
The SERVICE MENUS are displayed in five pages. Each page displays one or two submenus. Press the enter button
to highlight the submenus, and use the up or down button to scroll up or down. Press the enter button to enter the
selected submenu.
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Chapter 5 iCOM Controller 55
SERVICE MENUS
PASSWORD LEVEL
C / F
H%R
SE T
SETPOINTS
5.7.1 PASSWORD LEVEL
It is operated by Emerson service personnel.
5.7.2 SETPOINTS
Different from the SETPOINTS in the USER MENUS, the SETPOINTS in SERVICE MENUS has many more
parameters. See Table 5-11 for the parameter descriptions.
Parameters Default Setting range Description
S102 TEMP SET 23°C 5°C ~ 40°C Temperature setpoint
S103 CTRL TYPE PI Prop, PI, Intel, No Control type selection
S104 TEMP PB 7K 2.2K ~ 30K Temperature proportional band setpoint, or the P in PID control
S105 TEMP INT min - Temperature integration time setpoint, or the I in PID control
S107 AUTOSET Yes Yes, No Autoset enable
S108 TEMP DB 0K 0K~20K Temperature deadband setting range
S109 2ND SETP 23°C 5°C ~ 40°C -
S110 BACK TSP 23°C 5°C ~ 40°C Backup temperature setpoint
S111 HEAT DB 0K 0K~20K Heaters deadband setting range
S113 HUM SET 50% 1% ~ 80% Humidity setpoint
S114 HUM CTRL Pred Comp, Rel, Pred Humidity control type
S115 HUM PB 10% 1% ~ 20% Humidity proportional band
S116 HUM INT 5min - Humidity integration time
S117 HUM DB 0% 1% ~ 50% Humidity deadband setting range
S118 LO LIM 1 k - Dehum/Heat low limit 1
S119 LO LIM 2 -1.7K -5.5K ~ -1.1K Dehum/Heat low limit 2
S124 SUP SENS No No, Lim, Ctrl, Cool Supply air type
S125 SUP TEMP 5°C 5°C ~ 27°C Air supply limit temperature setpoint
S126 SUP TYPE PI Prop, PI, PID, Intel Supply control type
S127 SUP PB 12K 2K ~ 30K Supply proportional band
S128 SUINT 0min 0 ~ 15min Supply integration
S130 SUP DB - 0K~20K Supply deadband
S131 VPULS 5% 0 ~ 10% Valve Pulse
S132 CF0 - 0.01 ~ 100% Cooling filter at 0%
S132 CF100 - 0.01 ~ 100% Cooling filter at 100%
S133 RET CO 0K 0 ~ 10K Return Compensation
S135 AMB TYPE No CONT, EFC, VAL, No DT between Room/Outdoor Type
S136 AMB DT 5°C
S137 FC TYPE No No, CONT, VAL DT between Room/FC Type
S138 FC DT 4.5°C
S139 MIN CW No Yes, No Minimum CW temperature protection selection
S140 MIN CW 7°C 0 ~ 20°C Minimum CW temperature value
S141 LOCK FC 0°C 0 ~ 9°C Lockout FC at FC Fluid below
1 / 5
0?
SERVICE MENUS
SERVICE MENUS
???
WELLNESS
4 / 5
STANDBY
WELLNESS
CALIERATION
NETWORK
NETWORK SETUP
Figure 5-8 SERVICE MENUS
Table 5-11 Descriptions of SETPOINTS parameters
0
20°C
～
0
20°C
～
2 / 5
SERVICE MENUS
SET
UP
DT between Room Air/Outdoor
DT between Room Air/FC Fluid
SERVICE MENUS
SERVICE
SET
ALARMS
DIAGNOSTICS
SET ALARMS
5 / 5
OPTIONS SETUP
SERVICE INFO
3 / 5
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56 Chapter 5 iCOM Controller
Parameters Default Setting range Description
S142 TRANS CH 2% 0.1 ~ 100% Transition Change
S146 FANSPEED Auto
S147 VSD SET 100% 0 ~ 100% Standard speed of the unit
S148 VSD MIN 60% 0 ~ 100% Minimum speed of the unit
S149 VSD DEH 60% 0 ~ 100% Speed used during dehum
S150 VSD NOP 100% 0 ~ 100% Speed used when CI is active
S151 FF0% 0.2%/s 0 ~ 100%/s Fanspeed Change (at 0%)
S151 FF100% 1%/s 0 ~ 100%/s Fanspeed Change (at 100%)
S152 FRD 0s 0 ~ 300s Fanspeed Reposition Delay
S153 HAD - - -
S154 HAP 6°C 2 ~ 30°C Fanspeed P-Band
S155 HAI 5min 0 ~ 15min Fanspeed Integration
S157 SCR TYPE - - -
S158 CO1 ON - - -
S159 CO1 OFF - - -
S160 CO1 TD - - -
S161 CO2 ON - - -
S162 CO2 OFF - - -
S163 CO2 TD - - -
S164 CYCLET - - -
S165 SCR FACT - - -
S166 ACT SCR - - -
Auto, Man, ECO, SUP,
DELT
VSD Fanspeed
5.7.3 STANDBY
The parameters of the STANDBY menu are described in Table 5-12.
Parameters Default Setting range Description
S502 #STANDBY 1 0 ~ 32 Number of standby units
S503 ROTATION Daily
S504 ROT HOUR hr - Used to set the hour of the detailed time while rotation
S505 ROT MIN min - Used to set the minute of the detailed time while rotation
S506 ROT BY 1 1 ~ 8 The unit number for a rotation
S507 DO ROT No Yes, No Perform one rotation
S508 CASCADE No
S509 STBY HT No Yes, No Whether to start all standby units upon high temperature alarm
5.7.4 WELLNESS
Table 5-12 Descriptions of STANDBY parameters
Rotation frequency setting of the running and standby units. Range:
Daily: rotate once a day.
No, Daily,
MON ~ SUN,
M - MON ~ M
- SUN
CO/HE,
Cool, Yes,
No
MON ~ SUN: rotate once a week. The rotation occurs on Monday ~ Sunday
of the week. For example, MON means rotation occurs on Monday of every
week.
M - MON ~ M - SUN: rotate once a month. The rotation occurs on Monday ~
Sunday of the first week of the month. For example, M - MON means rotation
occurs on Monday of the first week of every month
Cascade function selection. ‘Yes’ corresponds to temperature and humidity
control and ‘no’ corresponds to closing the cascade
The iCOM controller calculates the bonus and penalty over the equipment maintenance based on the parameters in
the WELLNESS menu and the equipment operation historical data, so as to find out the next system maintenance
time.
Informing the maintenance personnel of the maintenance time makes the air conditioner run in the optimal mode,
which reduces the chances of faults and raises the system reliability.
The WELLNESS menu includes nine groups of parameters, including WELLNESS BASICs, and WELLNESS MOTOR,
WELLNESS COMPs, WELLNESS HEATs and WELLNESS HUM. See Table 5-13 ~ Table 5-21 for detailed parameter
descriptions.
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Chapter 5 iCOM Controller 57
WELLNESS BASIC1
Table 5-13 Descriptions of WELLNESS BASIC1 parameters
Parameters Default Setting range Description
S002 FREQ/YR 1pY 0pY ~ 12pY Maintenance frequency every year
S003 BONUS MM 0MM ~ 12MM Bonus setting
S004 PENALTY MM 0MM ~ 12MM Penalty setting
S005 LAST PM YY
S005 LAST PM MM
S005 LAST PM DD
-
Last maintenance. Year (YY), month (MM) and day (DD). This
parameter is read only
WELLNESS BASIC2
Table 5-14 Descriptions of WELLNESS BASIC2 parameters
Parameters Default Setting range Description
S006 NAME - - Service personnel setting
S007 CONFIRM No Yes, No Maintenance confirmation selection
S008 NEXT PM - - Calculated next maintenance. This parameter is read only
WELLNESS MOTOR
Table 5-15 Descriptions of WELLNESS MOTOR parameters
Parameters Default Description
S013 STARTS - Number of fan starts since the last maintenance
S014 RUN HRS hr Fan run hours since the last maintenance
S015 AVG RUN min Average fan run time calculated through number of fan starts and run hours
S016 BEST 1 Starts per day best
S017 WORST 24 Starts per day worst
S018 ALARMS 0 Number of alarms since the last maintenance
S019 BONUS 0MM
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
WELLNESS COMP1
Table 5-16 Descriptions of WELLNESS COMP1 parameters
Parameters Default Description
S024 STARTS - Number of compressor 1 starts since the last maintenance
S025 RUN HRS hr Compressor 1 run hours since the last maintenance
S026 AVG RUN min Average compressor 1 run time calculated through the number of starts and run hours
S027 BEST 12 Starts per day best
S028 WORST 240 Starts per day worst
S029 HP AL 0 Number of high pressure alarms occurred to compressor 1 since the last maintenance
S030 LP AL 0 Number of low pressure alarms occurred to compressor 1 since the last maintenance
S031 OL AL 0 Number of overload alarms occurred to compressor 1 since the last maintenance
S032 DS HT AL 0
S033 BONUS 0MM
Number of digital scroll high temperature alarms occurred to compressor 1 since the last
maintenance
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
WELLNESS COMP2
Table 5-17 Descriptions of WELLNESS COMP2 parameters
Parameters Default Description
S035 STARTS - Number of compressor 2 starts since the last maintenance
S036 RUN HRS hr Compressor 2 run hours since the last maintenance
S037 AVG RUN min Average compressor 2 run time calculated through the number of starts and run hours
S038 BEST 12 Starts per day best
S039 WORST 240 Starts per day worst
S040 HP AL 0 Number of high pressure alarms occurred to compressor 2 since the last maintenance
S041 LP AL 0 Number of low pressure alarms occurred to compressor 2 since the last maintenance
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58 Chapter 5 iCOM Controller
Parameters Default Description
S042 OL AL 0 Number of overload alarms occurred to compressor 2 since the last maintenance
S043 DS HT AL 0
S044 BONUS 0MM
WELLNESS HEAT1
Parameters Default Description
S046 STARTS - Number of electric heater 1 starts since the last maintenance
S047 RUN HRS hr Electric heater 1 run hours since the last maintenance
S048 AVG RUN min Average electric heater 1 run time calculated through the number of starts and run hours
S049 BEST 24 Starts per day best
S050 WORST 240 Starts per day worst
S051 ALARMS 0 Number of high pressure alarms since the last maintenance
S052 BONUS 0MM
WELLNESS HEAT2
Parameters Default Description
S057 STARTS - Number of electric heater 2 starts since the last maintenance
S058 RUN HRS hr Electric heater 2 run hours since the last maintenance
S059 AVG RUN min Average electric heater 2 run time calculated through the number of starts and run hours
S060 BEST 24 Starts per day best
S061 WORST 240 Starts per day worst
S062 ALARMS 0 Number of high pressure alarms since the last maintenance
S063 BONUS 0MM
WELLNESS HEAT3
Number of digital scroll high temperature alarms occurred to compressor 2 since the last
maintenance
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
Table 5-18 Descriptions of WELLNESS HEAT1 parameters
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
Table 5-19 Descriptions of WELLNESS HEAT2 parameters
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
Table 5-20 Descriptions of WELLNESS HEAT3 parameters
Parameters Default Description
S068 STARTS - Number of electric heater 3 starts since the last maintenance
S069 RUN HRS hr Electric heater 3 run hours since the last maintenance
S070 AVG RUN min Average electric heater 3 run time calculated through the number of starts and run hours
S071 BEST 24 Starts per day best
S072 WORST 240 Starts per day worst
S073 ALARMS 0 Number of high pressure alarms since the last maintenance
S074 BONUS 0MM
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
WELLNESS HUM
Table 5-21 Descriptions of WELLNESS HUM parameters
Parameters Default Description
S079 STARTS - Number of humidifier starts since the last maintenance
S080 RUN HRS hr Humidifier run hours since the last maintenance
S081 AVG RUN min Average humidifier run time calculated through the number of starts and run hours
S082 BEST 24 Starts per day best
S083 WORST 240 Starts per day worst
S084 ALARMS 0 Number of high pressure alarms since the last maintenance
S085 BONUS 0MM
Bonus amount. Actual bonus calculated through the number of starts and average run time.
This value determines the time for the next maintenance
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5.7.5 DIAGNOSTICS
The DIAGNOSTICS menu is classified into two groups. After entering the menu, pressing the up button and down
button can switch between two groups and pressing the enter button can enter the parameters of the corresponding
group. The parameters of group 1 are settable and used to help the maintenance personnel start and cut off devices
by hand in site, so as to realize the diagnosis for devices. The parameters of group 2 are read only and reflect the fault
condition of the devices. See Table 5-22 for detailed descriptions.
Parameters Default Setting range Description
S302 HP1 CODE 0 -
S303 HP2 CODE 0 -
S304 HT1 CNT 0 -
S305 HT2 CNT 0 -
S306 LP1 CODE 0 -
S307 LP2 CODE 0 -
S308 LP1 ACT bar - Actual LP 1
S309 LP2 ACT bar - Actual LP 2
S310 LP1 ACT bar - Actual LP 1
S311 LP2 ACT bar - Actual LP 2
S313 MANUAL No Yes, No
S314 MOTOR(S) On On, Off
S315 COMP1 Off On, Off
S315 C1 MODE Run
Group 1
S316 C1 CAP Off On, Off Refrigeration capacity output of digital scroll compressor 1
S317 C1 CYCLE 0% - -
S318 LLSV 1 Off On, Off Diagnostic of liquid line solenoid valve of compressor 1
S319 COMP2 Off On, Off
S319 C2 MODE Run
S320 C2 CAP Off - Refrigeration capacity output of digital scroll compressor 2
S321 C2 CYCLE 0% - -
S322 LLSV2 Off On, Off Diagnosis switch of liquid line solenoid valve of compressor 2
S324 EL HEAT1 Off On, Off.
S325 EL HEAT2 Off On, Off.
S326 EL HEAT3 Off On, Off.
S327 SCR HEAT - 0 ~ 100 % SCR Heat
S328 DEHUMl Off On, Off Diagnostic switch of Dehumidification solenoid valve
S329 HUM FILL Off On, Off
S330 HUM Off On, Off
Chapter 5 iCOM Controller 59
Table 5-22 Descriptions of DIAGNOSTICS parameters
HP 1 alarm counting. The counter can be reset to 0 through
the parameter
HP 2 alarm counting. The counter can be reset to 0 through
the parameter
HT 1 alarm counting. The counter can be reset to 0 through
the parameter
HT 2 alarm counting. The counter can be reset to 0 through
the parameter
LP 1 alarm counting. The counter can be reset to 0 through
the parameter
LP 2 alarm counting. The counter can be reset to 0 through
the parameter
Selecting ‘Yes’ can turn on or off the components; selecting
‘No’ can prohibit manual setting
Diagnosis switch of fan motor. The settings ‘On’ and ‘Off’ are
used to manually start and shut down the fan respectively
Diagnosis switch of compressor 1. The ‘On’ setting of this
parameter can start compressor 1 only when the fan has been
started
Run, Evac,
Charg
Run, Evac,
Charg
Compressor 1 operation mode selection
Diagnostic swtich of compressor 2. Note that the On setting of
this parameter can start compressor 2 only when the fan has
been started
Compressor 2 operation mode selection
Diagnosis switch of electric heater 1. The ‘On’ setting of this
parameter can start electric heater 1 only when the air loss is
normal
Diagnosis switch of electric heater 2. The ‘On’ setting of this
parameter can start electric heater 2 only when the air loss is
normal
Diagnosis switch of electric heater 3. The ‘On’ setting of this
parameter can start electric heater 3 only when the air loss is
normal
Diagnosis switch of solenoid valve of water supply to the
humidifier
Diagnosis switch of humidifier. The ‘On’ setting of this
parameter can start the humidifier only when the air loss is
normal
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60 Chapter 5 iCOM Controller
Parameters Default Setting range Description
S331 H DRAIN - On, Off Humidfier drain
S332 HUM.C. 0.00A - Electric current of humidifier
S335 ALM REL Off On, Off Diagnostic switch of alarm relay.
S336 K11 REL - On, Off Diagnostic switch of free cooling relay.
S337 3P1 OPEN Off On, Off
S337 3P2 OPEN Off On, Off
S338 3P1 CLOSE Off On, Off
Group 1
Group 2
S338 3P2 CLOSE Off On, Off
S339 BV CTRL - Man, Auto Ball valve control type
S340 MBV1 POS - 0 ~ 100%
S340 MBV2 POS - 0 ~ 100%
S341 ANALOG1 0% 0 ~ 100%
S342 ANALOG2 0% 0 ~ 100%
S343 ANALOG3 0% 0 ~ 100%
S344 ANALOG4 0% 0 ~ 100%
S345 RSD On On, Off Remote shut down. Range: On, Off
S346 AIR LOSS OK OK, ACT
S347 MOTOR OL ACT OK, ACT
S348 FILTER OK OK, ACT
S349 CUSTOM1 OK OK, ACT
S350 CUSTOM2 OK OK, ACT
S351 CUSTOM3 Ok OK, ACT
S352 CUSTOM4 OK OK, ACT
S353 HEAT SAF OK OK, ACT Status heaters safety
S354 FLOW AT % - -
S355 FLOW ACT % - -
S356 HP1 OK OK, ACT
S357 LP1 OK OK, ACT
S358 C1 OL OK OK, ACT
S359 HP2 OK OK, ACT
S360 LP2 OK OK, ACT
S361 C2 OL OK OK, ACT
S367 HUM PROB OK OK, ACT
S368 DT1 - OK, ACT Status DT1 (Outdoor/Glycol)
S369 DT2 - OK, ACT Status DT2 (Glycol/Room)
S370 DT3 On On, Off Status DT3 (Room/Setpoint)
S371 MIN CW - OK, ACT Status Min CW
S372 LWD Val - - S374 LSI - - -
S375 COND 2 - - S376 COND 1 - - -
S379 V_CTRL Time Time, Feedb Valve Control
S380 V_CAL No Yes. No Start Valve Calibration
S381 CAL_STAT Idle - S382 CLSD 1 - - -
S383 OPEN 1 - - -
S384 V1FDB - - S385 CLSD 2 - - -
S386 OPEN 2 - - S387 V2FDB - - -
Diagnostic switch of 3-phase electric regulator.
MBV1 position, MBV2 position
Diagnostic output of analog variable 1 ~ 4. They can be set to
be percentage of desired output
Air loss alarm. OK means the system is normal. ACT means
the air loss is active, and abnormity occurred
Fan motor overload alarm. OK means the fan is normal. ACT
means the fan is overloaded, and abnormality occurred
Filter clogging situation. OK means normal; ACT means the
filter is clogged
States of customized alarms 1 ~ 4. ‘OK ‘means normality;
‘ACT’ means that the alarm is active and that abnormality
occurs
State of high pressure switch 1. OK means normal. ACT
means abnormal
State of low pressure switch 1. OK means normal. ACT
means abnormal
Overload state of compressor 1. OK means normal. ACT
means abnormal
State of high pressure switch 2. OK means normal. ACT
means abnormal
State of low pressure switch 2. OK means normal. ACT
means abnormal
Overload state of compressor 2. OK means normal. ACT
means abnormal
Humidifer fault state. OK means normal. ACT means
abnormal
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5.7.6 SET ALARMS
The SET ALARMS menu is displayed in nine pages. The first page provides the settings of alarm upper/lower limits
and customized alarms. The other eight pages provide the settings of alarm delay.
Alarm upper/lower limits setting
The alarm upper/lower limits in the SERVICE MENUS are set the same as those in the USER MENUS. For details,
see Table 5-6.
Customized alarms setting
See Table 5-23 for the descriptions of customized alarms setting.
Parameters Default Parameters Default
S202 RTN SNSR Yes S215 LO SUP 10°C
S203 HI TEMP °C S224 CUST IN1 WATER
S204 LO TEMP °C S225 C1 ACT CLOSE
S205 HI HUM 60% S226 CUST IN2 WATER
S206 LOW HUM 40% S227 C2 ACT CLOSE
S207 SENSOR A No S228 CUST IN3 WATER
S208 HI TEMP A °C S229 C3 ACT CLOSE
S209 LO TEMP A °C S230 CUST IN4 HEAT A
S210 HI HUM A % S231 C4 ACT OPEN
S211 LO HUM A % S232 WA AC AL No
S213 SUP SNSR No S233 WAT OFF No
S214 HI SUP T 24°C
CUST IN1, CUST IN2, CUST IN3 and CUST IN4 can be set to 21 types of input. See Table 5-24 for details.
Types Description Types Description Types Description
SMOKE Smoke alarm RH+HU Rht + Hum lockout RJTVS HTRJ TVSS
WATER Water leakage alarm COMP Compressor lockout Fire Fire Alarm
C PMP Cooling pump alarm Call Call for service 2.Set 2nd Setpoint
FLOW Insufficient water alarm Temp High temperature alarm NoP No Power
G PMP Standby pump alarm Air Air loss alarm LSI LSI
STBY Standby unit alarm FC L. FC lockout Cnd 1 Condensor 1 Fail
C-In1 Customized alarm 1 HeatA Heater alarm Cnd 2 Condensor 2 Fail
C-In2 Customized alarm 2 FLOSD Flow AL SD ScRed D-Scroll Red
C-In3 Customized alarm 3 FLOLC Flow AL LC Swap V Swap Valve
C-In4 Customized alarm 4 ComPD Comp Lock PD ECFan EC Fan Fail
RHT Reheater lockout En FC Enable FC,
HUM Humidifier lockout
C1 ACT, C2 ACT, C3 ACT and C4 ACT correspond to the customer alarms. ‘OPEN’ means normally open, ‘CLOSE’
means normally closed.
Alarm delays setting
Chapter 5 iCOM Controller 61
Table 5-23 Descriptions of customized alarms setting
Table 5-24 Descriptions of types
RJVFD HTRJ VFD
The alarm delays are the time after faults occur and before the alarms are triggered. See Figure 5-9 for the menu
format.
2/10
FOL
LOA
CF
HRT
LRT
HRH
DEL EN
5
3
2
30
30
30
S236
S237
S238
S239
S240
S241
Figure 5-9 Alarm delay
Yes
Yes
Yes
Yes
Yes
Yes
01SET ALARMS
T
ALM
ALM
WRN
WRN
WRN
WRN
The alarm name, delay time, delay enabling and alarm type are displayed from left to right in the list.
The alarm delay can be set to 0 ~ 9999. Unit: second.
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62 Chapter 5 iCOM Controller
The delay enabling determines whether the alarm will be displayed and the alarm menu is entered, Options include
‘Yes’ and ‘No’.
The alarm type can be set to ‘ALM’ (alarm), ‘WRN’ (warning) and ‘MSG’ (message). They determine the alarm degree
of the corresponding event.
The alarm names are listed in Table 5-25.
SN
S236 FOL Fan overload S266 LOF Loss of flow
S237 LOA Loss of airflow S267 SGP Standby glycol pump on
S238 CF Filter clogged S268 STB Standby unit on
S239 HRT High room temp. S269 HUP Humidifier problem
S240 LRT Low room temp. S270 NOC No connection w/Unit1
S241 HRH High room hum. S271 - No connection w/UnitX
S242 LRH Low room hum. S272 LOP LOSS OF POWER
S243 HTA High temperature of sensor A S275 CI1 Customized input 1
S244 LTA Low temperature of sensor A S276 CI2 Customized input 2
S245 HHA High humidity of sensor A S277 CI3 Customized input 3
S246 LHA Low humidity of sensor A S278 CI4 Customized input 4
S249 OL1 Compressor 1 overload S279 CS Call for service
S250 OL2 Compressor 2 overload S280 HTD High temperature
S251 HP1 Compressor 1 high pressure S281 LB1 Loss of air blower 2
S252 HP2 Compressor 2 high pressure S282 RL Reheat lockout
S253 LP1 Compressor 1 low pressure S283 HL Humidifier lockout
S254 LP2 Compressor 2 low pressure S284 FCL FC lockout
S255 PD1 Compressor 1 pumpdown fails S285 CL Compressor(s) lockout
S256 PD2 Compressor 2 pumpdown fails S288 SC1 Short cycle 1
S257 HT1 Digital scroll 1 high temperature S289 SC2 Short cycle 2
S258 HT2 Digital scroll 2 high temperature S290 NOP NO power
S259 EHO EL HEAT HIGH TEMP S291 CN1 Condensor 1 Fail
S262 WHE Working hours exceeded S292 CN2 Condensor 2 Fail
S263 SMO Smoke detected
S264 WUF Water under floor S294 HST High supply air temperature
S265 CPH Conderser pump high water S295 LST Low supply air temperature
Alarm/event
name
Table 5-25 Alarm name description
Description SN
S293 EFF EC Fan fail
Alarm/event
name
Description
5.7.7 CALIBRATION
The CALIBRATION menu can calibrate sensors by setting offsets. The parameters are listed in Table 5-26. The
parameters are in pairs: the former is the calibrated value and the latter is the calculated value, or the sum of the
measured value and the calibrated value. This value is engaged in the calculation of control need.
Parameters Default Description
S602 RTN TEMP K
S603 CAL TEMP 25°C
S604 RTN HUM +0.0%
S605 CAL HUM 44.0%
S606 DS1 NTC +0.0K
S607 CAL DS1 29°C
S608 DS2 NTC +0.0K
Table 5-26 Descriptions of CALIBRATION parameters
Calibrated return air temperature. It can be set as a positive or negative value. Use the up
and down buttons to change the setting value, 0.1K at each step
Sum of the calibrated value and measured return air temperature. This value is compared
with the setting value as the system actual temperature and is engaged in the calculation
Calibrated return air humidity. It can be set as a positive or negative value. Use the up and
down buttons to change the setting value, 1% at each step
Sum of the calibrated value and measured return air humidity. This value is compared with
the setting value as the system actual humidity and is engaged in the calculation
Calibrated digital scroll 1NTC. It can be set as a positive or negative or positive value. Use
the up and down buttons to change the setting value, 0.1K at each step
Sum of the calibrated value and return air humidity measured by digital scroll 1NTC
sensor. This value is engaged in the calculation
Calibrated digital scroll 2NTC. It can be set as a positive or negative value. Use the up and
down buttons to change the setting value, 0.1K at each step
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Chapter 5 iCOM Controller 63
Parameters Default Description
S609 CAL DS2 29°C
S610 OUT SNS °C Outdoor Sensor
S611 CAL OUT +0.0K Calibrated Outdoor Sensor
S613 TEMP A +0.0K Calibrated value of temperature sensor A
S614 CAL A °C Calculated value corresponding to temperature sensor A
S615 HUM A +0.0% Calibrated value of humidity sensor A
S616 CAL A 44.0% Calculated value corresponding to humidity sensor A
S617 TEMP B TH Calibrated value of temperature sensor B
S618 TYPE B +0.0K Type of temperature sensor B
S619 CAL B °C Calculated value corresponding to temperature sensor B
S620 HUM B +0.0% Calibrated value of humidity sensor B
S621 CAL B 44.0% Calculated value corresponding to humidity sensor B
S622 TYPE C TH Type of temperature sensor C
S624 FC SNSR -
S625 FC SNSR +0°C Calibrated value of free cooling temperature sensor
S626 CAL FC °C Calculated value of free cooling temperature sensor
S627 SUP SNSR NTC Air supply temperature sensor. PTC or NTC sensor can be configured
S628 SUP TEMP +0.0K Calibrated value of air supply temperature sensor
S629 CAL SUP °C Calculated value of air supply temperature sensor
S630 TEMP C +0.0K Calibrated value of temperature sensor C
S631 CAL C °C Calculated value of temperature sensor C
S632 HUM C +0.0% Calibrated value of humidity sensor C
S633 CAL C % Calculated value of humidity sensor C
Sum of the calibrated value and return air humidity measured by digital scroll 2NTC
sensor. This value is engaged in the calculation
Free cooling temperature sensor. PTC or NTC sensor can be configured according to the
actual configuration
5.7.8 NETWORK SETUP
The NETWORK SETUP menu is used to set the parameters when the system is in a network subject to the monitoring
of a host. See Table 5-27 for parameter descriptions.
Parameters Default Setting range Description
S802 #UNITS 1 1 ~ 32 Range: 1 ~ 32
S803 TEAMWORK No No, 1, 2 Range: No, 1, 2
S824 MON ADD 3 1 ~ 99 Monitoring address No. of the unit
S825 MON T.O. No No, 1, 2 Monitoring Timeout
S825 MON H.S. 3 1 ~ 99 Monitoring Handshake
S831 CS CTRL No
S831 CS STAT Change Change, Valid
S832 NW CTRL No
S832 NW STAT Valid Change, Valid
S835 MON PROT Vlcty
S836 IP #1 192
S836 IP #2 168
S836 IP #3 254
S836 IP #4 1
S837 NM #1 255
S837 NM #2 255
S837 NM #3 255
S837 NM #4 0
Table 5-27 Descriptions of NETWORK SETUP parameters
Save, Load,
No
Save, Load,
No
Vlcty, HN,
IGM, No
- Set IP address
- Set subnet mask
Save the parameter set through MON ADD to the iCOM controller.
‘No’ means not saved
Indication of the saving state of the parameter set through MON
ADD. ‘Change’ means that the parameter is changed but not saved.
‘Valid’ means that the setting is valid and saved
Save the parameter set through U2U GRP to the iCOM controller.
‘No’ means not saved
Indication of the saving state of the parameter set through U2U
GRP. ‘Change’ means that the parameter is changed but not saved.
‘Valid’ means that the setting is valid and saved
Host monitoring protocol setting. Range: Vlcty (Velocity uses
intelligent card), HN (Hironet), IGM (ECA2), No
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64 Chapter 5 iCOM Controller
Parameters Default Setting range Description
S838 GW #1 0
S838 GW #2 0
S838 GW #3 0
S838 GW #4 0
S840 U2U PROT GBP - -
S841 U2U ADD 3 - Group address No. of this unit
S842 U2U GRP 1 - -
S843 BL CTRL No S + R, No
S843 BL STAT Change Change, Valid
S844 SR CTRL No C + R, No
S844 SR STAT Valid - STD
SW# - - Version No. of the control software
MAC
NAME UNIT UNIT
00:00:68:19:
31:70
- Set gateway address
Boot program variant load. Saving the change of S835 ~ S841 needs
the S + R command of this parameter. The system will reset after the
saving, and configure according to the new parameters
Indication of whether or not the parameters set through S835 ~ S841
are saved. ‘Change’ means that the parameter is changed but not
saved. ‘Valid’ means that the setting is valid and saved
Static RAM data reset control. If the change of S835 ~ S841 are not
saved, using the C + R command in this parameter can restore S835
~ S841 to their original settings, and the system will reset afterwards
00:00:68:19:3
1:70
MAC address of the network card of the iCOM controller
Name of the unit. By default: UNIT. You can change the name as
you need
5.7.9 OPTIONS SETUP
The OPTIONS SETUP menu is used to set the parameters according to the equipment-specific demands. See Table
5-28 for detailed descriptions.
Parameters Default Setting range Description
S402 COMP SEQ Auto
S403 LP DELAY 1min - Low pressure alarm delay
S405 EL HEAT 1 0 ~ 3 Electric heating stages
S406 EL HEAT C - - -
S407 HW HEAT No Yes, No Hot water heating enabled
S408 ALL HEAT 3 0 ~ 3 heating stages.
S409 LWDconn No Yes, No
S409 V_CTRL Time Time, Feedback -
S410 3P RUN 165s - 3P actuator runtime
S411 3P DIR DIR DIR, REV 3P actuator direction
S413 HUM ENAB Yes Yes, No Humidification enabled
S414 IR FLUSH 150% - Infrared flush rate
S415 HUMSTEAM % - -
S416 HUM CONT On, Off On, Off, Prop Humidifier control mode
S417 HUM.TIME s - Humidifier bottle flush time
S418 HUM.MAN Yes Yes, No Humidifier bottle manual flush enabled
S419 DEHUM EN Yes Yes, No Dehumidification enabled.
S420 REST EN Yes Yes, No Auto restart enabled
S421 RESTART s - Unit auto restart time
S422 ONOFF EN Yes Yes, No
S424 CW FLUSH 0hr - Cooling water auto flush time, unit: hr (hour)
Table 5-28 Descriptions of OPTIONS SETUP parameters
Auto, 1
(compressor 1
being the
primary one), 2
(compressor 2
being the
primary one)
Compressor sequence. Range: Auto, 1 (compressor 1 being the
primary one), 2 (compressor 2 being the primary one)
LWD connected. Range: Yes (water low sensor connected), No
(water low sensor not connected)
On-off key enabled. If “no” is selected, the ON/OFF key cannot be
used to perform on/off operation on the machine.
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Parameters Default Setting range Description
S425 FC FLUSH 0hr - Free cooling auto flush time, unit: hr (hour)
S426 HT FLUSH 0hr - Hot water auto flush time, unit: hr (hour)
S427 BALL OFF +0.0bar - -
S428 HEAT AS - - -
S429 CW_CTRL - - -
S430 MAIN V - - -
S431 VALV ROT - - -
S432 VALV TIM - - -
S433 DEHUM OP - - -
5.7.10 SERVICE INFO
The SERVICE INFO menu provides the contact information of maintenance personnel. The maintenance personnel
can input and save their contact information through this submenu.
5.8 ADVANCED MENUS
The ADVANCED MENUS include PASSWORD LEVEL, FACTORY SETUP and PASSWORDS, as shown in Figure
5-10.
Chapter 5 iCOM Controller 65
5.8.1 PASSWORD LEVEL
It is operated by Emerson service personnel.
5.8.2 FACTORY SETUP
The FACTORY SETUP menu is displayed in nine pages. The parameters are described in Table 5-29 ~ Table 5-38.
Unit code related settings
Parameters (1/9) Default Setting range Description
A003 UC 01 0
… … …
A003 UC 06 0
A005 UC 07 0
… … …
A005 UC 12 0
A007 UC 13 0
… … …
A007 UC 18 0
A008 UC CTRL No
ADVANCED MENUS
PASSWORD LEVEL
FACTORV SETUP
SET
Figure 5-10 ADVANCED MENUS
Table 5-29 Descriptions of unit code related settings
-
Save, Load,
Compare, No
1 / 2
3
ADVANCED MENUS
????
ACCESS
Unit code setting. The code has 18 bits. Each bit can be set as 0 ~
20
Options include:
Save: after UC01 ~ UC18 are changed, the changed can be saved
through the save command.
Load: load parameters to the unit code directly.
Compare: compare the present parameters and the parameters to
be loaded.
No: All changes are cancelled. Keep the old parameters
PASSWORDS
2 / 2
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66 Chapter 5 iCOM Controller
Parameters (1/9) Default Setting range Description
A009 UC STAT OK
A010 EL CTRL Load - External data can be loaded through the load command
A011 EL STAT OK
System related settings
Parameters (2/9) Default Setting range Description
A102 REFRIG R22
A103 MOTOR OL SHUTD
A104 AIR LOSS SHUTD
A105 # COMP 0 0 ~ 2 Number of compressors
A106 COMP DLY s - Compressor delay time
A107 COMP ON min 0 ~ 5min Compressor minimum on time
A108 COMP OFF 3min 0 ~ 5min Compressor minimum off time
A109 PUMPDOWN Yes Yes, No Pump down enable
A110 CAP TYPE No
A111 FLOCT 0s 0 ~ 180s Shutdown time of airflow loss
Other settings
Unit code status. Range:
Not available,
Invalid, OK,
Changed,
Updating
Not available,
Invalid, OK,
Changed,
Updating
Table 5-30 Descriptions of system related settings
R407C, R22,
R410A
SHUTD,
DISAB
SHUTD,
DISAB
4step,
HGBP, DS,
DS + TH, No
Not available: parameters set through UC01 ~ UC18 are
unavailable.
Invalid: parameters set through UC01 ~ UC18 are invalid.
OK: parameters set through UC01 ~ UC18 are effective.
Changed: parameters UC01 ~ UC18 are changed, but not saved.
Updating: parameters are updating
Exception list status. Range:
Not available: parameters set through UC01 ~ UC18 are
unavailable.
Invalid: parameters set through UC01 ~ UC18 are invalid.
OK: parameters set through UC01 ~ UC18 are effective.
Changed: parameters UC01 ~ UC18 are changed, but not saved.
Updating: parameters are updating
Refrigerant type selection
Main fan overload. The action to take after the fan overload. Range:
SHUTD (fan shuts down), DISAB (shut down humidifier, dehumidifier and
heater, only keep the cooling unit running)
The action to take after the loss of airflow. Range: SHUTD (fan shuts
down), DISAB (shut down humidifier, dehumidifier and heater, only keep
the cooling unit running)
Capacity control type. 4step: four steps. HGBP: hot gas bypass. DS:
digital scroll. DS + TH: digital scroll and temperature switch. No: with no
need for capacity control type
Table 5-31 Descriptions of other settings
Parameters (3/9) Default Setting range Description
A113 DS CYCLE s - Digital scroll cycle
A114 DS HT °C - Digital scroll high temperature
A115 DS SWB °C - Digital scroll switchback
A116 LP TYPE Analog Analog, Digital Low pressure device type
A117 LP PH1 ps - Low pressure threshold phase 1
A118 LP PH2 ps - Low pressure threshold phase 2
A119 LC PRE 0.0s - Liquid control pre-time
A120 LC POST 0.0s - Liquid control post-time
A121 CHARGE P bar - Loss of Charge Protection
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Chapter 5 iCOM Controller 67
LP sensor related settings
Table 5-32 Descriptions of LP sensor related settings
Parameters (4/9) Default Setting range Description
A124 LP1 LOW 10% 0 ~ 100% LP1 sensor lower threshold (percentage)
A124 LP1 LOW 0bbar 10 ~ 50bar LP1 sensor lower threshold
A125 LP1 HIGH 90% 0 ~ 100% HP1 sensor lower threshold (percentage)
A125 LP1 HIGH 10.3bar 10 ~ 50bar HP1 sensor lower threshold
A126 LP1 ACT - - Actual LP1 signal. Read only
A127 LP2 LOW 10% 0 ~ 100% LP2 sensor lower threshold (percentage)
A127 LP2 LOW 0bar 10 ~ 50bar LP2 sensor lower threshold
A128 LP2 HIGH 90% 0 ~ 100% HP2 sensor lower threshold (percentage)
A128 LP2 HIGH 10.3bar 10 ~ 50bar HP2 sensor lower threshold
A129 LP2 ACT - - Actual LP2 signal. Read only
A130 PD CUT bar - Pumpdown cutout
A131 PD RECYC bar - Pumpdown recycle
A132 HEAT REJ W/G
FSC, L-T,
W/G
Heat rejection control. Range:
FSC: fan speed control; L-T: Lee-Temp; W/G: water/glycol cooling
Free-cooling, HG and HW related settings
Table 5-33 Descriptions of free-cooling, HG and HW related settings
Parameters (5/9) Default Setting range Description
WNG
DEH、NOP、FC
A135 K11 ACT DEH
A136 C/W F DUR 3min 1min ~ 3min Cooling water flush duration
A137 COOL TYP SINGL Singl, FC, DC Three cooling type
A138 STOP FC+ °C - Stop FC at setpoint + or value
A139 FC F DUR 0min 1min ~ 3min Freecooling flush duration
A140 FC F K11 Yes Yes, No Freecooling flush starts R5
A141 COMP + FC No Yes, No Compressor plus FC simultaneously
A142 HW F DUR 3min 0 ~ 3min Hot water flush duration
A143 HG HEAT No Comp.1, Comp.2, No Hot gas heating enabled
A144 HEAT OP STAGE Stage, Delay, No Electric heater operation mode
、
-
Humidification and dehumidification related settings
Table 5-34 Descriptions of humidification and dehumidification related settings
Factory 6/9 Default Setting range Description
External, IFS, IFL,
PEX6, PEX9, PEX12,
A146 HUM TYPE IFS
A147 HUM VOLT V - -
A148 HUM LAST 15hr -
A149 PREFILL 30s or 57s - Prefill time. Unit: second
A150 FILL 57s - Fill time. Unit: second
A151 HUM ON 584s - Humidifier on time. Unit: second
A152 DEH COMP 1 1, 2, both
21LLA, 53LLC,
53HLB, 93LLE,
93HLD, d3H, HT2,
HT5, HT9, SGH, No
Humidifier model
Detect whether the last operation time exceeds this cycle
setting during the startup of the humidifier. Unit: hr
Dehumidification with compressor. When 1 or 2 is selected,
compressor 1 or 2 is used for dehumidification. When Both
is selected, the two compressors are both used for
dehumidification
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68 Chapter 5 iCOM Controller
Analog output related settings
Factory 7/9 Default Setting range Description
A157
A157
A158
A158
A159
A159
A160
A160
A161
A163
A164
A165
A166
ANOUT1LO 0% 0 ~ 100%
ANOUT1HI 100% 0 ~ 100%
ANOUT2LO 0% 0 ~ 100%
ANOUT2HI 100% 0 ~ 100%
ANOUT3LO 0% 0 ~ 100%
ANOUT3HI 100% 0 ~ 100%
ANOUT4LO 0% 0 ~ 100%
ANOUT4HI 100% 0 ~ 100%
FS HE/HU 100% 0 ~ 100%
ANOUT1 No -
ANOUT2 No -
ANOUT3 No -
ANOUT4 No -
Options Description Options Description
CW010 CW/FC 0 ~ 10V ALBD2 AlarmBoard 2
HW Hot water ALBD3 AlarmBoard 3
HW175 Hot water 1.75 IVAR I-Variex 1
VSD Variable fan speed drive HUM% HT HUM
COOL Cooling SUP Supply Temperature
CV175 CW/FC 1.75 RET Return Temperature
COOL1 Cooling 1 HUMI Humidifier
COOL2 Cooling 2 SUPSA Supersaver
HEAT Heater INVCO Inverted Cool
No No use HEAT3 Heating 33%
MBV1 Motorized ball vavle1 CW210 CW/FC 2 ~ 10V
MBV2 Motorized ball vavle 2 C2010 CW2 0 ~ 10V
SCR Silicon controlled rectifier C2175 CW2 1.75
CONF Configurable C2210 CW2 2 ~ 10V
ALBD1 AlarmBoard 1
Analog action related settings
Table 5-35 Descriptions of analog output related settings
-
Analog output selection. See Table 5-36
Table 5-36 Descriptions of analog output options
Table 5-37 Descriptions of analog action related settings
Parameters (8/9) Default Setting range Description
A168 AO1 STA 0% 0% ~ 100% Analog output 1 start percentage
A168 AO1 STA 0V 0V ~ 10V Analog output 1 start voltage
A169 AO1 END 100% 0% ~ 100% Analog output 1 end percentage
A169 AO1 END 10V 0V ~ 10V Analog output 1 end voltage
A170 AO2 STA 0% 0% ~ 100% Analog output 2 start percentage
A170 AO2 STA 0V 0V ~ 10V Analog output 2 start voltage
A171 AO2 END 100% 0% ~ 100% Analog output 2 end percentage
A171 AO2 END 10V 0V ~ 10V Analog output 2 end voltage
A172 AO3 STA 0% 0% ~ 100% Analog output 3 start percentage
A172 AO3 STA 0V 0V ~ 10V Analog output 3 start voltage
A173 AO3 END 100% 0% ~ 100% Analog output 3 end percentage
A173 AO3 END 10V 0V ~ 10V Analog output 3 end voltage
A174 AO4 STA 0% 0% ~ 100% Analog output 4 start percentage
A174 AO4 STA 0V 0V ~ 10V Analog output 4 start voltage
A175 AO4 END 100% 0% ~ 100% Analog output 4 end percentage
A175 AO4 END 10V 0V ~ 10V Analog output 4 end voltage
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LL related settings
Parameters (9/9) Default Setting range Description
A179 LL1 LOW %
A179 LL1 LOW bar
A180 LL1 HIGH %
A180 LL1 HIGH bar
A181 LL1 ACT %
A182 LL1 ACT bar
A183 LL2 LOW %
A183 LL2 LOW bar
A184 LL2 HIGH %
A184 LL2 HIGH bar
A185 LL2 ACT %
A186 LL2 ACT bar
5.9 MBV Settings
Through the ADVANCED MENUS screen (see Figure 5-11), you can view the current status of the cooled valve. MBV
menu is displayed in six pages, and the description of the menus is listed in Table 5-39.
Table 5-38 Descriptions of LL related settings
0 ~ 100%
10.0 ~ 50.0bar
0 ~ 100%
10.0 ~ 50.0bar
-
-
0 ~ 100%
10.0 ~ 50.0bar
0 ~ 100%
10.0 ~ 50.0bar
-
-
HPT1 low limit percentage setting
HPT1 low limit setpoint
HPT1 high limit percentage setting
HPT1 high limit setpoint
HPT1 actual percentage, read only
HPT1 actual value, read only
HPT2 low limit percentage setting
HPT2 low limit setpoint
HPT2 high limit percentage setting
HPT2 high limit setpoint
HPT2 actual percentage, read only
HPT2 actual value, read only
Chapter 5 iCOM Controller 69
ADVANCED MENUS
SET
MBV
ACCESS
MBV SETTINGS
...
settings of the m otorized ball valve
▲
to change level
▲
to open requested menu
←
Figure 5-11 ADVANCED MENUS screen
Table 5-39 MBV settings
Parameters Default Range Description
A403 UNIT HI PRESS - - Unit high pressure
A404 MBV OP PRESS - - MBV control available pressure
A405 MBV POSITION - - MBV position
A406 ACTIVE OFFSET - - Active offset
A408 MBV PHASE - - -
A409 COMPR LP PHASE - - -
A410 MBV PRESS READ - - -
A411 MBV POSITION SET - - -
A414 START OFFSET - - -
A415 MAX OFFSET STEP - - -
A416 SERVICE OFFSET - - -
A417 START DELAY - - -
A418 STOP DELAY - - -
A419 4ST OPEN PRESET - - -
A420 4ST CLOSE PRESET - - -
A424 MBV REINT - - -
A425 READ INTERVAL - - -
A426 DIG SCROLL FILTER - - -
A427 4ST-30SEC LOADING - - -
A428 PUMPDOWN PRESS - - -
A431 REPOSITION COUNTER - - MBV reposition counter
▲
▲
▲
to navigate
▲
←
ESC to unselect
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70 Chapter 5 iCOM Controller
Parameters Default Range Description
A432 REPOSITION COUNTER RESET - - Reposition counter reset
A436 U4 - - U4 proportional band
A437 U3A - - U3A proportional band
A438 U2A - - U2A proportional band
A439 U1 - - U1 proportional band
A440 L1 - - L1 proportional band
A441 L2A - - L2A proportional band
A442 L3 - - L3 default proportional band
A443 ACTIVE OFFSET - - ACTIVE OFFSET
A444 4ST PHASHE - - 4ST PHASHE
A447 MAX - - Max proportional band
A448 U4 - - U4 default proportional band
A449 U3A - - U3A default proportional band
A450 U3B - - U3B default proportional band
A451 U2A - - U2A default proportional band
A452 U2B - - U2B default proportional band
A453 U1 - - U1 default proportional band
A458 L1 - - L1 default proportional band
A459 L2A - - L2A default proportional band
A460 L2B - - L2B default proportional band
A461 L3 - - L3 default proportional band
A462 MIN - - Min proportional band
5.10 EVENT NAME AND DEFINITION
See Table 5-40 for event name and definition.
Table 5-40 List of event name and definition
Event Definition
General Alarm General Alarm
COMP 1 HIGH PRESSURE Compressor 1 high pressure
COMP 1 LOW PRESSURE Compressor 1 low pressure
HIGH CW TEMP Chilled water high temperature
LOSS OF CW FLOW Loss of chilled water
EL HEAT HIGH TEMP Electric heater high temperature
MAIN FAN OVERLOAD Main fan overload
LOSS OF AIRFLOW Loss of air flow
CLOGGED FILTERS Clogged filters
CUSTOMER INPUT n (n = 1 ~ 4) Customer input n (n = 1 ~ 4)
FC LOCKOUT Free cooling lockout
LP Transducer 1 Fail Low pressure transducer 1 fails
CALL SERVICE Call for service
HIGH TEMPERATURE High temperature alarm
LOSS OF AIR BLOWER 1 Loss of air blower 1
HIGH ROOM TEMP High room temperature
LOW ROOM TEMP Low room temperature
HIGH ROOM HUM High room humidity
LOW ROOM HUM Low room humidity
HIGH TEMP SENSOR A High temperature of sensor A
LOW TEMP SENSOR A Low temperature of sensor A
HIGH HUM SENSOR A High humidity of sensor A
LOW HUM SENSOR A Low humidity of sensor A
UNIT HRS EXCEEDED Unit has exceeded operating time
COMP 1 HRS EXCEEDED Compressor 1 has exceeded operating time limit
HUM HRS EXCEEDED Humidifier has exceeded operating time limit
SUPPLY SENSOR FAILURE Supply sensor failure
DSCROLL 2 SENSOR FAIL Digital scroll 2 sensor fails
ROOM SENSOR FAILURE Room sensor failure
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Chapter 5 iCOM Controller 71
Event Definition
SENSOR A FAILURE Sensor A failure
LP Transducer 2 Fail Low pressure transducer 2 fails
NETWORK FAILURE Network failure
Low Start Pressure 1 Alarm of low start pressure 1
UNIT ON Unit on
UNIT OFF Unit off
SLEEP MODE Sleep mode
STANDBY MODE Standby mode
POWER ON Power on
POWER OFF Power off
Unit n disconnected (n = 1 ~ 32) Unit n disconnected (n = 1 ~ 32)
COMP 2 HIGH PRESSURE Compressor 2 high pressure
COMP 2 LOW PRESSURE Compressor 2 low pressure
COMP 2 HRS EXCEEDED Compressor 2 has exceeded operating time limit
DSCROLL 1 SENSOR FAIL digital scroll 1 sensor fails
FREECOOL TEMP SENSOR Free cooling source sensor failure
Low Start Pressure 2 Alarm of low Start Pressure 2
ON-OFF KEY DISABLED ON-OFFkey disabled
LWD SENSOR FAIL Low water level sensor fails
WATER LEAKAGE Water leakage alarm
Dummy 67 Dummy alarm 067
RAM / Battery Failure RAM/battery failure
Low Memory 1 Low memory 1
NO CONNECTION w/Unit1 No connection with unit 1
COMP 1 OVERLOAD Compressor 1 overload
COMP 2 OVERLOAD Compressor 2 overload
WRONG DAMPER POSITION Wrong damper position
Dummy 074 Dummy alarm 074
HP 1 SENSOR FAIL High pressuresensor 1 fails
HP 2 SENSOR FAIL High pressure sensor 2 fails
COMP POWER REDUCTION ACTIVE Compressor power reduction active
NO POWER No power
UNIT DISABLED Humidification/heating disabled due to unit failure
UNIT SHUT DOWN Unit shutdown due to failure
Low Coil Pressure 1 Low coil pressure 1
Low Coil Pressure 2 Low coil pressure 2
Low OP Pressure 1 Low op pressure 1
Low OP Pressure 2 Low op pressure 2
UNIT SYNCHRONISATION Unit recovers online
HUMIDIFIER PROBLEM Humidifier failure
REMOTE SHUTDOWN Remote shutdown
DEHUM HRS EXCEEDED Dehumidifier has exceeded operating time limit
FC HRS EXCEEDED Free cooling source has exceeded operating time limit
C1 FREEZE PROTECTION Compressor 1 freeze protection
COMP 1 PUMPDOWN FAIL Compressor 1 pumpdown fails
MEMORY 1 FAIL Memory 1 fail
MEMORY 2 FAIL Memory 2 fail
HCB not connected Humidifier contorl board not connected
BMS Disconnected Battery management system disconnected
COMP 2 PUMPDOWN FAIL Compressor 2 pumpdown fails
DIG SCROLL1 HIGH TEMP Digital scroll 1 high temperature
DIG SCROLL2 HIGH TEMP Digital scroll 2 high temperature
Dummy 099 Dummy alarm 099
RESERVED 100 Reserved 100
RESERVED 101 Reserved 101
RESERVED 102 Reserved 102
Dummy 103 Dummy alarm 103
SMOKE DETECTED Smoke detected
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Event Definition
WATER UNDER FLOOR Water leakage under floor
COND PUMP-HIGH WATER Condensing pump high water level
LOSS OF FLOW Loss of water flow
STBY GLYCOL PUMP ON Standby glycol pump on
STANDBY UNIT ON Standby unit on
HW/HG HRS EXCEEDED Hot water/hot gas has exceeded operating time limit
EL HEAT1 HRS EXCEEDED Electric heater 1 has exceeded operating time limit
EL HEAT2 HRS EXCEEDED Electric heater 2 has exceeded operating time limit
EL HEAT3 HRS EXCEEDED Electric heater 3 has exceeded operating time limit
UNIT CODE MISSING Unit code missing
UNIT CODE n MISMATCH (n = 01 ~ 18) Unit code n mismatch (n = 01 ~ 18)
FRONT DOOR OPEN Front door not closed
REAR DOOR POEN Rear door not closed
LOSS COMPRESSOR POWER Loss of compressor power
CABINET SENSOR FAIL Cabinet sensor fail
CABINET H-SENSOR FAIL Cabinet H-sensor fail
EMERGENCY DAMPER FAIL Emergency damper fails
HIGH CABINET TEMP High cabinet temperature
LOW CABINET TEMP Low cabinet temperature
HIGH EXT DEWPOINT High external dewpoint
LOSS OF POWER Loss of power
REHEAT LOCKOUT Reheater lockout
HEAT REJ VFD HEAT REJ VFD
HUMIDIFIER LOCKOUT Humidifier lockout
HEAT REJ TVSS HEAT REJ TVSS
COMPRESSOR (S) LOCKOUT Compressor lockout
AMBIENT SENSOR FAIL Ambient sensor fail
HUMIDIFIER LOW AMPS Humidifier low current
COMP 1 SHORT CYCLE Compressor 1 short cycle
COMP 2 SHORT CYCLE Compressor 2 short cycle
HUMIDIFIER HIGH AMPS Humidifier high current
HUMIDIFIER LOW WATER Humidifier low water level
SYSTEM OFF REQUESTED System off requested
SYSTEM OFF CONFIRMED System off confirmed
C2 FREEZE PROTECTION Compressor 2 freeze protection
FIRE ALARM Fire alarm
HEATERS OVERHEATED Heaters overreheated
CONDENSER 1 FAILURE Condenser 1 failure
CONDENSER 2 FAILURE Condenser 2 failure
HUM CYLINDER WORN Humidifier cylinder worn
FC STOPPED FOR 1 HOUR Free cooling stopped for 1 hour
MAINTENANCE DONE Maintenance done
MAINTENANCE NEEDED Maintenance needed
REDUCED ECO AIRFLOW Reduced eco airflow
LOSS OF FLOW PUMP 1 Loss of flow pump 1
LOSS OF FLOW PUMP 2 Loss of flow pump 2
COMP 3 HIGH PRESSURE Compressor 3 high pressure
COMP 4 HIGH PRESSURE Compressor 4 high pressure
CONDENSATION DETECTED Condensation detected
COMP 1 LOW PRESSURE Compressor 1 low pressure
HIGH REF TEMPERATURE High refrigerant temperature
LOW REF TEMPERATURE Low refrigerant temperature
REFRIGERANT SENSOR FAIL Refrigerant sensor fail
HIGH TEMP SENSOR B High temperature sensor B
LOW TEMP SENSOR B Low temperature sensor B
COMP 2 LOW PRESSURE Compressor 2 low pressure
SENSOR B FAILURE Sensor B failure
COMP 3 SHORT CYCLE Compressor 3 short cycle
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Event Definition
COMP 4 SHORT CYCLE Compressor 4 short cycle
HIGH DEWPOINT High dewpoint
PUMP SHORT CYCLE Pump short cycle
Top Fan Failure Top fan failure
CONTROL VALVE FAILURE Control valve failure
PUMP 1 HRS EXCEEDED Pump 1 has exceeded operating time limit
PUMP 2 HRS EXCEEDED Pump 2 has exceeded operating time limit
COMP 3 HRS EXCEEDED Compressor 3 has exceeded operating time limit
COMP 4 HRS EXCEEDED Compressor 4 has exceeded operating time limit
TANDEM 1 PUMPDOWN FAIL Tandem 1 pumpdown fail
TANDEM 2 PUMPDOWN FAIL Tandem 2 pumpdown fail
TANDEM 1 LOW PRESSURE Tandem 1 low pressure
TANDEM 2 LOW PRESSURE Tandem 2 low pressure
HIGH FLUID TEMPERATURE High fluid temperature
LOW FLUID TEMPERATURE Low fluid temperature
FLUID SENSOR FAILURE Fluid sensor failure
FAN FAILURE Fan failure
FEEDBACK SIGNAL 1 FAILURE Feedback signal 1 failure
SUPPLY CW SENSOR FAILURE Supply chilled water sensor failure
RETURN CW SENSOR FAILURE Return chilled water sensor failure
SUPPLY REF SENSOR FAILURE Supply refrigerant sensor failure
RETURN REF SENSOR FAILURE Return refrigerant sensor failure
VALVE HRS EXCEEDED Valve has exceeded operating time limit
COMP 1A HIGH PRESSURE Compressor 1A high pressure
COMP 1B HIGH PRESSURE Compressor 1B high pressure
COMP 2A HIGH PRESSURE Compressor 2A high pressure
COMP 2B HIGH PRESSURE Compressor 2B high pressure
COMP 1A HRS EXCEEDED Compressor 1A has exceeded operating time limit
COMP 1B HRS EXCEEDED Compressor 1B has exceeded operating time limit
COMP 2A HRS EXCEEDED Compressor 2A has exceeded operating time limit
COMP 2B HRS EXCEEDED Compressor 2B has exceeded operating time limit
COMP 1A SHORT CYCLE Compressor 1A short cycle
COMP 1B SHORT CYCLE Compressor 1B short cycle
COMP 2A SHORT CYCLE Compressor 2A short cycle
COMP 2B SHORT CYCLE Compressor 2B short cycle
HIGH SUPPLY TEMPERATURE High supply temperature
LOW SUPPLY TEMPERATURE Low supply temperature
HIGH RETURN HUMIDITY High return humidity
LOW RETURN HUMIDITY Low return humidity
NOISE RED MODE STARTED Noise reduced mode started
NOISE RED MODE STOPPED Noise reduced mode stopped
RACK SENSOR 1~10 FAILURE Rack sensor 1 ~ 10 failure
HIGH RETURN TEMPERATURE High return temperature
ROOM HUMIDITY PROBLEM Room humidity problem
iCOM-DO #0 ~ #2 DISCONNECTED iCOM-do #0 ~ #2 disconnected
FEEDBACK SIGNAL 2 FAILURE Feedback signal 2 failure
BOTTOM FAN FAILURE Bottom fan failure
EC FAN FAULT EC fan fault
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Chapter 6 Application Of INTELLISLOT
This chapter introduces the application of the host communication component INTELLISLOT, including introduction
and installation of the host communication cards, commissioning of the host communication component and host
communication networking diagram.
6.1 Introduction Of Host Communication Cards
The host communication configuration of the Liebert.PEX series air conditioner supports the following two
communication cards:
1. TCP/IP communication card
The TCP/IP communication card is shown in Figure 6-1. This card can provide a network port and MIB library, and you
can browse the data through IE.
口调试
Console port
网口
Network port
Figure 6-1 TCP/IP communication card
2. 485 communication card
The 485 communication card is shown in Figure 6-2. This card can provide the Modbus protocol of the RS485 port to
the host.
RS485 口
RS485 port
Figure 6-2 485 communication card
6.2 Installation Of Host Communication Cards
Installing host communication card
The installation boxes 1 and 2 have been installed on the Liebert.PEX series air conditioner unit. If the host
communication configuration is needed, insert the host communication card into the installation box 1 and tighten the
screws, as shown in Figure 6-3.
调试口
Console port
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Connecting cables
Chapter 6 Application Of INTELLISLOT 75
Bolts
Communication card
Installation box 1
Installation box 2
Figure 6-3 Installing communication card
The electrical schematic diagram of the host communication configuration is shown in Figure 6-4. Cables P61, P65
and P67 have been connected in factory. So you should only connect the host communication card to the monitoring
center.
P61
P65
485 or TCP/IP communication card
P67
iCOM control board
Figure 6-4 Electrical schematic diagram of host communication configuration
Standard diplay screen
Intellislot
6.3 Commission Of Host Communication Component
After the communication cable is connected, you can start to set the HyperTerminal and communication card
parameters.
Note
Before commissioning, you must enter ‘SERVICE MEMUS’ of the iCOM controller to set S824 MON ADD to ‘3’, S835 MON
PORT to ‘Vlcty’ and S843 BL CTRL to ‘S+R’.
Communication
cable
Monitoring center
6.3.1 Setting HyperTerminal
After the 485 communication card and TCP/IP communication card are set, they can communicate with the host
monitoring system. Use the communication cable provided with the communication card to connect the serial port of
the computer and the console port of the communication card, and then set the parameters using the HyperTerminal of
Windows. The detailed setting procedures are as follows:
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1. Click Start-> Programs -> Accessories -> Communications -> HyperTerminal to start the HyperTerminal, as
shown in Figure 6-5.
tt
2. Type the name ‘tt’ in the Name field, and click OK, as shown in Figure 6-6.
Figure 6-5 Typing the name
tt
Figure 6-6 Choosing serial port
3. In the Connect To interface, choose the serial port being used (such as ‘COM1’), and click OK, as shown in Figure
6-7.
Figure 6-7 Setting port property
4. Set the communication parameters as shown in Figure 6-7 and click OK.
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6.3.2 Setting 485 Communication Card
Set the parameters of the 485 communication card according to the following procedures:
1. After the HyperTerminal is set, you can click
2. Type ‘1’ and the following figure will appear.
Chapter 6 Application Of INTELLISLOT 77
OK to display the following HyperTerminal interface.
3. Type ‘1’ and the following figure will appear.
4. Type ‘1’ and select the Modbus protocol, and the following figure will appear.
5. Type ‘3’ and select the ID used to communicate between the communication card and the host, and the following
figure will appear.
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6. Type the server ID following the command prompt, and the following figure will appear.
7. Type ‘4’ and the following figure will appear.
8. Type ‘1’, ‘2’ or ‘3’ to select the baud rate used to communicate with the host, and the following figure will appear.
9. Press the ESC button to return to the main interface.
If you type ‘x’, the setting can be saved. After the setting is saved, the 485 communication card will be restarted.
10. On the main interface, typing ‘4’ can view whether the communication status between the communication card and
the Liebert.PEX series air conditioner is normal, as shown in the following figure.
6.3.3 Setting TCP/IP Communication Card
Set the parameters of the TCP/IP communication card according to the following procedures:
1. After the HyperTerminal is set, you can click
OK to display the following HyperTerminal interface.
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2. Type ‘2’ and the following figure will appear.
Chapter 6 Application Of INTELLISLOT 79
3. Type ‘1’ and the following figure will appear.
Normally, Boot mode should be set to Static. If the user network can automatically distribute the address, select
DHCP, and the IP Address, Netmask and Default Gateway do not need to be set. If the boot mode is static, Type ‘3’, ‘4’
and ‘5’, and then respectively type the corresponding IP address, Netmask and Default Gateway according to the
prompt. These three parameters should be given by the user.
4. Press the ESC button to return to the main interface, as shown in the following figure. If you type ‘x’, the setting can
be saved. After the setting is saved, the TCP/IP communication card will be restarted.
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5. On the main interface, typing ‘5’ can view whether the communication status between the communication card and
the Liebert.PEX series air conditioner is normal, as shown in the following figure.
6.3.4 Setting SNMP Parameters Of TCP/IP Communication Card
After the HyperTerminal of the TCP/IP communication card is set, you can set the parameters of this communication
card. The detailed setting procedures are as follows:
1. Type the IP address of the TCP/IP communication card in the address bar of the IE browser. If the interface shown
in Figure 6-8 appears, it indicates that the communication between the communication card and the iCOM controller is
abnormal. If the
with the iCOM controller.
State shows Completing or In Process, it indicates that the communication card is communicating
Figure 6-8 Initial interface (1)
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Chapter 6 Application Of INTELLISLOT 81
After the communication becomes normal, the interface shown in Figure 6-9 will appear.
Figure 6-9 Initial interface (2)
2. Click the configure tab to enter the configuration interface, as shown in Figure 6-10.
Figure 6-10 Configuration interface
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3. Click Access under SNMP at the left side of the interface, as shown in Figure 6-11. Type the user name ‘Liebert’
and the password ‘Liebert’, and click
OK to enter the configuration interface.
Note
The user name and password are case-sensitive.
Connect to
Username
Password
Figure 6-11 Typing user name and password
4. Configure the Network Management System (NMS) of the host monitoring center in Figure 6-12. Click Edit and type
the IP address of the NMS in
IP Address. Select read or write, type ‘Public’ in Community and then click Save.
OK Cancel
Note
1. Before setting the NMS, the Edit button is displayed on the interface. After the configuration is edited, the Edit button will
become the Save button.
2. After the NMS is configured, you must click Save to save the configuration.
Figure 6-12 NMS configuration interface of SNMP host monitoring center (1)
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Chapter 6 Application Of INTELLISLOT 83
5. Expand the SNMP node at the left side of the interface shown in Figure 6-13 and click Traps to set IP Address,
Port and Community of the NMS used for receiving Traps. After modifying, you must click Save to save the setting.
Figure 6-13 NMS configuration interface of SNMP host monitoring center (2)
6.4 Host Communication Networking Diagram
The networking diagram of the TCP/IP communication card (SNMP protocol) is shown in Figure 6-14. The connection
number of air conditioner is not limited.
Network cable
Air conditioner 1 TCP/IP
communication card
Air conditioner 2 TCP/IP
communication card
…
Air conditioner n TCP/IP
communication card
Figure 6-14 Networking diagram of TCP/IP communication card
Note
The single air conditioner unit does not need HUB.
The networking diagram of the 485 communication card (Modbus protocol) is shown in Figure 6-15. Up to 32 air
conditioner units can be connected.
Air conditioner 1 485
communication card
Air conditioner 2 485
communication card
Air conditioner 32 485
communication card
Figure 6-15 Networking diagram of 485 communication card
connection
Network cable
connection
Network cable
connection
…
485 connection
485 connection
485 connection
HUB
485 connection
Network cable
connection
Monitoring center
Monitoring center
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Chapter 7 System Operation And Maintenance
This chapter introduces the operation and maintenance of the Liebert.PEX series air conditioner.
7.1 System Diagnosing Test
7.1.1 Self-diagnosis Function
Regular system maintenance is vital to ensure product reliability and availabilities.
The iCOM controller features a diagnostic function that enables you to turn on/off the components in site manually so
as to check their functionality. For the operation instruction, see
Warning
1. During the operation of the Liebert.PEX air conditioner system, lethal voltage may be present in the internal components. It is
a must to obey all the notes and warnings marked on the equipment or contained in this manual, otherwise injury or fatality may
occur.
2. Only qualified maintenance personnel can operate and handle the components.
5.7.5 DIAGNOSTICS.
7.1.2 Electric Control Part
Maintenance of electric part
Carry out visual inspection and handle the electric connection by referring to the following items.
1. Conduct overall electrical insulation test: find out the unqualified contacts and handle them. Note to disconnect the
fuses or MCBs of the control part during the test lest the high voltage should damage the control components.
2. Check the contactors before power-on and make sure the contactors can act freely without obstruction.
3. Clean the electric and control elements of dust with brush or dry compressed air.
4. Check the closing of contactors for arcs or signs of burning. Replace the contactor if necessary.
5. Fasten all the electric connection terminals.
6. Check that the sockets and plugs are in good condition. Replace those loosened ones.
Maintenance of control part
Carry out visual inspection, simple function test and handle the control parts by referring to the following items.
1. Visually inspect the power transformers and isolation transformers, and test the output voltage (of the indoor unit
and outdoor condenser).
2. Check that there is no signs of aging on the control interface board, display control board, sensor board and fuse
board.
3. Clean the electric control elements and control board of dust and dirt with brush and electronic dust removing agent.
4. Check and fasten the I/O ports at the control interface board, including the connection between display control
board and control interface board, as well as between the temperature/humidity sensor board and the interface board.
5. Check the connection between the user terminals (70#, 71#, 70A#, 71A#, 37#, 38#, 77#, 78#) and the control
interface board.
6. Check the output connection between the control interface board and various components, including various
contactors, solenoid valves for liquid pipes and bypass solenoid valves (liquid bypass), and the input connection
between control interface board and various components, including fan overload protector, high pressure and low
pressure switches, heating over-temperature safties, humidifier safties, filter clogging switch, pressure difference
switch, high/low pressure sensor and chilled water temperature sensor. In particular, check the connection parts such
as HP/LP switches and solenoid valves, and replace the component if in poor connection or faulty.
7. Check and replace electrical components that are faulty, such as control fuses (or MCBs) and control boards.
8. Check the specification and condition of the control cable and power cable between the indoor unit and the
condenser, and replace the cable when necessary.
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9. Use temperature and humidity measuring meters with higher precision to measure and calibrate the temperature
and humidity sensors.
Note
Set the humidity control mode to ‘relative humidity control’ during calibration process.
10. Adjust the setpoints. Check the action of the functional parts and the auto-flush control logic of water pan of the
infrared humidifier according to control logic.
11. For dual cooling unit, use the gauge with higher temperature and precision to check and calibrate the sensor
temperature of the free cool system.
12. Simulate and check the operation of the protection devices including high and low pressure alarm, high and low
temperature alarm, high water level alarm and over-temperature protection.
13. Check the following external sensors.
1) Smoke sensor (optional).
The power supply of the smoke sensor is located at the bottom (or top) of the upflow (or downflow) unit. It constantly
samples the air, analyzes the samples and makes judgment. It requires no calibration.
2) Water detection sensor.
Bridge the water detection sensor probes and confirm the alarm through the iCOM controller.
The sensor should be placed away from any water pool or drainage trench on the floor, 2m ~ 2.5m away from the unit.
Do not place it directly under the unit. The recommended installation location of the water detection sensor is shown in
Figure 7-1.
Liebert unit
Location of water
detection sensor
Location of water
detection sensor
Drain pipes on the ground
Figure 7-1 Recommended location for the water detection sensor
Note
1. Before fastening the connection of any mechanical parts or cables, make sure that the power supply of the control unit has
been disconnected.
2. Do not use the water detection sensor adjacent to flammable liquid or use it to detect flammable liquid.
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7.2 Filter
To ensure efficient operation, the filter must be checked once a month, and be replaced as required.
Switch off the power before replacing the filter. You do not need to adjust the setpoint of the filter clog switch if the new
filter is of the same model. Otherwise, you need to adjust the setpoint. The filter clog switch is located in the electric
control box. It compares the air pressures before and after the filter through a black hose.
To adjust the setpoint of the filter clog switch, you should:
1. After replacing the filter, restore and seal all the panels, so that the alarm point can be found precisely.
2. With the fan running, rotate the rotary switch of the filter clogging switch counter clockwise to trigger the filter alarm.
3. Rotate the rotary switch clockwise for 1 rotation, or rotate it to the required filter replacing point.
Note
1. Set the setpoint properly. Otherwise, the filter alarm may be triggered too frequently; or, in the opposite case, the dust
accumulation on the filter could not trigger the alarm, resulting in low system airflow and endangering the system operation.
2. If you are unsure about the setpoint, consult Emerson before using a filter of a different model to replace the old one.
7.3 Fan Components
7.3.1 FC Fan
The fan components that require regular checking include belt, motor bracket, fan bearing and blades.
The fan and the installation board are designed in consistency. The belt tension is regulated automatically under the
force of gravity to reduce the fan vibration and protect the belt.
Fan bearing and blades
Check the fan regularly to make sure the bearing is secure. Rotate the blades and make sure that they do not contact
the housing. Because the bearing is permanently sealed and self-lubricated, check for signs of wearing when
adjusting the belt. Roll the belt and observe the motion of the fan bearing. If any abnormal displacement is observed,
replace the bearing.
Belt
Measure the belt tension with a tension meter. You can also press down the belt at the middle point between the two
pulleys. The displacement should be 12mm ~ 25mm (1/2” ~ 1”).
If the belt is found worn or distorted, replace it with a new belt. The new belt should be of the same model as the old
one.
Motor
To replace the failed motor, you need to be very careful, especially with the upflow unit. Use a dedicated fixture to hold
the motor before removing the fixing bolts at the bottom of the motor.
7.3.2 EC Fan
The EC fan needs main power supply with 380Vac input, meanwhile, it exercises the speed regulation according to the
0 ~ 10Vdc analog signals output from the control board. If the EC fan is in abnormal state, please check the analog
signals and main power supply carefully.
Besides, the main fan overload alarm of the control board is series connected with the alarms of the EC fan. When the
EC fan is over hot, loss of main power supply and clogging, the unit will generate EC fan fault alarm.
7.4 Infrared Humidifier
During the normal operation of the infrared humidifier, sediment will accumulate on its water pan. To ensure efficient
operation of the infrared humidifier, you need to clean the sediment regularly. However, the cleansing cycle varies
because the water is different in different regions. It is recommended to check, and cleanse (when necessary) the
water pan, once a month.
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Remove the water level standpipe to drain the water pan. Disconnect the drainage pipe, remove the safety switch of
the water pan, remove the fixing screws at the two ends of the pan, and pull out the water pan. Cleanse the water pan
with water and hard brush, and restore the water pan by reversing the preceding procedures.
Note
Before exercising the corresponding operation, make sure that the power has been cut off so as to avoid the personal injury; and
also ensure that the water in the water pan is close to the room temperature before pouring away the water from the infrared
humidifier water pan.
The autoflush function of the infrared humidifier can prolong the cleansing cycle. However, regular checks and
maintenance are necessary.
Replacing the lamps of the infrared humidifier
The lamp of the infrared humidifier is shown in Figure 7-2.
Infrared humidifier lamp Fixing screw of lamp wires
Ceramic socket
Lamp supporting bracket
Infrared lamp
Figure 7-2 Lamps of infrared humidifier
Fixing screw of wires
Lamp supporting bracket
Fixing screw of
ceramic socket
Follow the following procedures to replace it:
1. Turn off the power to the main isolation switch.
2. Unplug all the control cables of the infrared humidifier and cut the fixing cable tie binding the infrared humidifier
power cable. In the one-bay system, the plugs of the infrared humidifier are sealed in the niche above the lamp, and
you need to open the cover plate in front of the infrared humidifier before you can reach the plugs. The plugs of the
two-bay system and three-bay system are located at the left side of the infrared humidifier and are accessible directly.
3. After draining the water in the water pan, remove the drain pipe, remove the two fixing screws on both sides of the
infrared humidifier, and then pull out the infrared humidifier.
4. Open the cover plate (for one-bay system, this cover plate has been opened in step 2) to reveal the ceramic socket.
Use a multi-meter to locate the burned lamp.
5. Remove the water pan of the infrared humidifier.
6. Remove the brackets in the middle that support the lamps.
7. Remove the screws that fix the cables of the lamp to be replaced from the ceramic sockets (note to hold the lamp
with hand).
8. Remove the faulty lamp.
9. Install a new lamp.
Note
Do not touch the quartz lamp with bare hands! Greasy sediment and finger prints can seriously shorten the life span of quartz
lamps. Therefore, wear clean cotton gloves during the operation.
10. Restore the infrared humidifier by reversing step 3 ~ step 7.
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Autoflush system of the infrared humidifier
Note
The normal operation of the autoflush system, the humidifier demands a water source with minimum water flow of 1gpm (0.063
l/s) and minimum pressure of 20PSIG (138kPa).
The autoflush control program is an integral part of the infrared humidifier system. The program automatically controls
a water makeup valve to maintain the proper water level in the water pan of the infrared humidifier during the
humidification operation. When a call for humidification exists, the program checks how long the infrared humidify has
been off.
1. If the humidifier off time is equal to or greater than the programmed value (factory default is 15hr), the iCOM
controller assumes that the pan is dry and a program called pre-fill is initiated to add water to the water pan. The pre-fill
time is different according to the different water pan size. During the pre-fill operation, the infrared lamps of the infrared
humidifier are inactive.
2. If the off time of infrared humidifier is less than the programmed value, the pre-fill program will be ignored, and the
humidification status will be appeared. At this point, the infrared lamps are energized and the water makeup valve is
opened to fill water in the water pan.
During normal infrared humidification operation, the water makeup valve will operate the periodically based on the
evaporation of water from the pan. Water is added after eight minutes humidification of the small water pan and ten
minutes humidification of the large water pan, so as to complement the water volume due to humidified consumption,
and clear the mineral floating on the water pan surface. According to the different parts of the water quality, you can
set the water volume yourself. In general, the water volume can be adjusted from 110% to 500% in 1% increments
(default: 150%).
The automatic flushing system washes the water pan of the infrared humidifier to prevent erosion caused by sediment
minerals produced in the water. As the water source regulation is different, the water volume flowing through the
system can be set by using the program to meet local needs. The selectable range of water volume is the water flush
rate of between 110% ~ 500%. After the selection of water volume, the flushing system will run automatically, without
the need for any further adjustment. See Figure 7-3 for humidification logic.
7.5 Electric Heater
Check the rustiness condition of the electric heater; if possible, use the iron brush to get rid of the rust, or replace it.
The electric heater includes two types: upflow and downflow, as shown in Figure 7-4. Three temperature switches are
series connected to the control loop inside the electric heater, including two automatic reset switches and one manual
reset switch. When there is heating requirement, but no heating effect, you should use a multimeter to check whether
the cable used to temperature switch is in action, so as to ensure the three temperature switches are in normal state. If
the cable is not in action, you should remove the electric heater to check whether the manual reset switch is
disconnected, the automatic reset switch or the electric heater pipe is damaged.
Call for humidification
Note:
HMV: humidifier valve
IFS: Infrared small pan
IFL: Infrared large pan
On in last
15 hours?
Yes
HMV and
lamps on
4min: IFS
7min: IFL
Humidification
lamps only
8min: IFS
10min: IFL
Figure 7-3 Humidification logic
No
HMV pre-fill
IFS: 30s
IFL: 60s
refill
110%～500%
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Manual reset switch
Manual reset switch
Automatic reset switch
Chapter 7 System Operation And Maintenance 89
Automatic reset switch
Upflow electric reheat
7.6 Cooling System
Check the cooling system components once a month to make sure the system function is normal and that there are no
signs of wearing. Because the failure or damage of components is usually accompanied by corresponding faults,
regular check is a major means to prevent most system faults. The refrigerant pipes must be supported by properly set
brackets, and be laid away from the ceiling, floor or anywhere that vibrates. Check the refrigerant pipes and fixing
brackets every six months.
Each system has a sight glass to facilitate the observation of refrigerant flow and the system moisture content. When
the system moisture content is too high, the sight glass color will be changed. ‘Bubbles’ can indicate a shortage of
refrigerant subcooling.
When the cooling system is faulty, you can locate the fault by referring to certain parameters of system operation.
7.6.1 Suction Pressure
The compressor may stop when the suction pressure drops below the setpoint of the low pressure switch. On the
other hand, too high suction pressure will undermine the cooling effect of the refrigerant on the compressor motor,
leading to the damage of the compressor. The minimum (pressure switch action setpoint) and the maximum (design
operation value) suction pressures are listed in Table 7-1.
System Minimum pressure kPa (PSIG), R22 Maximum pressure kPa (PSIG), R22
Air-cooled (stepless fan speed controller) 138 (20) 620 (90)
Water-cooled 138 (20) 620 (90)
Downflow electric reheat
Figure 7-4 Upflow electric reheat and downflow electric reheat
Table 7-1 Suction pressure
7.6.2 Discharge Pressure
The discharge pressure may change with the load or the condenser efficiency. When the discharge pressure rises to
the setpoint of the pressure switch, the high pressure switch will act to stop the compressor. See Table 7-2 for details.
System design kPa (PSIG)
Air-cooled 1750 (251)
Water-cooled
Maximum pressure 2275 (330)
High pressure switch action point 2760 (400)
7.6.3 Suction Superheat Degree
The thermal expansion valve (TXV) can regulate the suction superheat degree. Follow the following procedures to
determine the system suction superheat degree.
1. Measure the temperature of the suction pipe at the TXV sensing bulb.
2. Sample the compressor suction pressure at the schrader valve of the suction pipe.
3. Evaluate the pressure difference between the sensing bulb and schrader valve of the suction pipe.
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Table 7-2 Discharge pressure
Water at 65°F ~ 75°F 1400 (203)
Water at 85°F 1450 (210)
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90 Chapter 7 System Operation And Maintenance
4. Add the sum of the preceding two pressures to find out the saturation temperature corresponding to the saturation
pressure.
The difference between the suction temperature at the sensing bulb and the saturation temperature is the suction
superheat degree. Try to achieve suction superheat between 5k ~ 8k.
Note
The suction superheat degree is critical to the compressor lifespan. If the compressor runs with little or no suction superheat
degree for a long time, slugging may occur to the compressor, damaging the scroll plate of the scroll compressor.
7.6.4 Thermal Expansion Valve
Operation
The auto-regulation of the thermal expansion valve guarantees sufficient refrigerant for the evaporator in order to meet
the needs of the load. The superheat degree is an indicator of the operation state of thermal expansion valve. If the
refrigerant to the evaporator is insufficient, the superheat degree will be high; and if the refrigerant to the evaporator is
too much, the superheat degree will be low. The proper superheat degree is 5k ~ 8k.
Regulation
Follow the following procedures to regulate the superheat degree setting.
1. Unscrew the bonnet at the bottom of the expansion valve.
2. Rotate the rotary switch counter clockwise to reduce the superheat degree.
3. Rotate the rotary switch clockwise to raise the superheat degree.
Note
1. Every time you rotate the rotary switch, do not rotate it for more than one round, and it may take up to 30mins to reach a new
balance.
2. Before delivery, the refrigerant of water-cooled unit has been charged, and the thermal expansion valve position has been
adjusted, so it is recommended not to adjust it on site. If you need to adjust the thermal expansion valve position, please contact
the technical support.
7.6.5 Hot Gas Bypass Valve (For Single Compressor System)
When the heat load in the room is not high, the single compressor system can regulate the indoor temperature by
using the hot gas bypass valve. In this way, the frequent use of the compressor is avoided, and energy saving effect is
realized. The hot gas bypass is shown in Figure 7-5.
Dehumidification
除湿电磁阀
solenoid valve
压缩机
Compressor
蒸发器
Evaporator
Expansion valve
膨胀阀
Hot gas bypass
solenoid valve
Water flow
Water in pipe
进水管路
Water out pipe
出水管路
regulating valve
Figure 7-5 Hot gas bypass solenoid valve
Liebert.PEX2 Series Air Conditioner User Manual
板式换
BPHE
热器
Page 96
7.6.6 Air-Cooled Condenser
Refer to 4.1 Maintenance in Liebert.PEX Condenser User Manual.
7.6.7 Water-Cooled Condenser
BPHE
The turbulence generated in the ducts of soldered BPHE can clean the ducts. However, on occasions when scaling is
serious, like when hot hard water is used, it is necessary to use cyclic rinsing device to clean the BPHE. Put weak acid
(like 5% phosphoric acid) into a jar and use a pump to inject the fluid into the BPHE to clean it. If the BPHE is often
cleaned, use 5% oxalic acid.
The cleaning of the BPHE is not covered by Emerson maintenance service. If necessary, you can consult Emerson
service personnel.
Electronic ball valve
The iCOM controller controls the electronic ball valve position by collecting the refrigerant pressure of the BPHE outlet
from the pressure sensor, so as to control the water flow through the BPHE for system stable operation. The higher the
load is, the more water flow is allowed to flow through the BPHE. The lower the load is, the less water flow is allowed
to flow through the BPHE.
Test function
If the electronic ball valve is in abnormal regulation state, please consult Emerson service personnel.
Chapter 7 System Operation And Maintenance 91
7.6.8 Compressor
Warning
No direct contact between the refrigerant or lubricant and the skin when replacing the compressor, or serious burning or frostbite
may occur. Put on gloves with long sleeves when processing polluted parts.
The Liebert.PEX air conditioner system uses the Copeland scroll compressor with high efficiency and high reliability. It
is rare for the motor of the compressor to get burned due to short circuit. In the few cases that the motor does get
burned, the cause is usually mechanical problem or poor lubrication, in other words, due to over-temperature.
If the causes that lead to the compressor failure could be discovered and corrected in time, most failures are avoidable.
The maintenance personnel should check the operation situation periodically and take necessary measures to ensure
the system normal operation. This practice is both easy and cost saving, when you compare it with replacing the
compressor upon faults that result from negligence or inadequate maintenance.
When diagnosing the compressor, check the operation situation of all the electric parts of the compressor.
1. Check all the fuses and circuit breakers.
2. Check the operation of high pressure and low pressure switches.
3. When the compressor is faulty, find out the nature of the cause: is it an electrical fault or a mechanical fault?
Mechanical faults
It is impossible to diagnose a mechanical fault of the compressor by smelling the burning. You should try spinning the
motor. If the fault is proved to be mechanical, the compressor has to be replaced. If the motor is burned, you should
remove the fault that leads to the burning of the motor and clean the system. It must be pointed out that the
compressor motor is usually burned because the system is not cleaned properly.
Electric faults
You can tell an electric fault by the unpleasant smell. If serious burning occurred, the lubricant will appear black and
become acidic. When electric fault occurs and the compressor motor is entirely burned, the system must be cleaned to
remove the acid material from the system and to avoid such faults in the future.
Note
The damage to the compressor components due to improper cleaning is classified in the warranty agreement as improper use of
the product, thus is not covered by the warranty.
Liebert.PEX2 Series Air Conditioner User Manual
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92 Chapter 7 System Operation And Maintenance
When the compressor is entirely burned, you need to replace the filter drier together with the compressor. In addition,
check the expansion valve. If the valve is faulty, replace it too. Before the replacement, you must clean the system. If
you are unsure about the cleaning method, please consult Emerson service personnel.
Compressor replacing procedures
1. Cut off the power supply.
2. Connect the LP and HP tubes of the pressure gauge to the schrader valves of the suction and exhaustion pipes
respectively to recycle the refrigerant.
Note
The refrigerant must be recycled or disposed in accordance with the local regulations. Discharging the refrigerant into the air is
harmful to the environment and illegal.
3. Disconnect all the electric connection to the compressor.
4. Disconnect the Rotalocks from the discharge and suction openings on the compressor.
5. Remove the faulty compressor (The compressor of the downflow fan unit has a higher location, so each unit is
configured with compressor replacement frock. For details, see label indication pasted behind the left front door of the
unit).
6. If the compressor has been entirely burned, you need to clean the pipes of the cooling system and replace the filter
drier.
Note
Do not remove the rubber bungs from the suction opening and exhaust opening of the new compressor too early. The time that
the openings are exposed to the air should not exceed 15mins so as to prevent the compressor refrigeration oil from absorbing
water and bringing the water inlet to the system.
7. Install the new compressor, and connect the pipes and electric cables.
8. Evacuate the system and add refrigerant in accordance with the commissioning regulations.
9. Power on the system by following the ordinary startup commissioning procedures and check the system operation
parameters. Observe the refrigerant state through the sight glass, determine the amount of refrigerant to be added by
considering the system pressure and temperature, and stop adding refrigerant until the system enters normal
operation.
Liebert.PEX2 Series Air Conditioner User Manual
Page 98
Chapter 8 Troubleshooting 93
Chapter 8 Troubleshooting
This chapter introduces the troubleshooting. You can read this chapter by referring to the part related to the alarms.
Warning
Certain circuits carry lethal voltages. Only professional technicians are allowed to maintain the unit. Extra care should be taken
when troubleshooting online.
Note
If jumpers are used for troubleshooting, remember to remove the jumpers after the troubleshooting, or the connected jumpers
may bypass certain control function and damage the equipment.
The troubleshooting of components is listed in Table 8-1 ~ Table 8-4.
Table 8-1 Fan fault removal
Symptom Potential causes Items to be examined or handled
No main power supply Examine the rated voltage of L1, L2 and L3 of the fan
FC fan cannot
be started
EC fan cannot
be started
Circuit breaker
disconnection
Overload, circuit breaker
disconnection
Contactor not pulling on
Control board failure
Fuse panel failure
Air flow loss switch alarm
(action)
The fan is ineffective Replace the fan
Circuit breaker
disconnection
Contactor cannot close
Control board failure
Fuse panel failure
Contactor closed, air flow
lose switch alarm
Examine the circuit breaker of main fan
Manual reset. Examine the current value
Examine whether there is 24Vac voltage between P36-3 and E1. If there is, but
the contactor cannot pull on, then the contactor has failures. Please replace the
contactor
Examine whether there is 24Vac voltage between P36-3 and E1. If there is not,
then the control panel has failures. Please check whether the green LED beside
silicon control Q5 on the control panel is on or not
Examine whether there is 24Vac voltage between P36-3 and E1. If there is not,
and the green LED beside Q5 is not on, please check further whether LED DS4
beside F4 on the fuse panel is on, or take down F4 to test whether it is burnt out
1) Check that the belt is firm and the fan motor is normal;
2) Check whether the external static pressure (ESP) is too high, if so, fix it by
optimizing the air channel and adjusting the belt setting value properly
Examine the circuit breaker of main fan
Examine whether there is 24Vac voltage between P36-3 and E1. If there is, but
the contactor cannot close, then the contactor has failures. Please replace the
contactor
Examine whether there is 24Vac voltage between P36-3 and E1. If there is not,
then the control panel has failures. Please check whether the green LED beside
silicon control Q5 on the control panel is on or not
Examine whether there is 24Vac voltage between P36-3 and E1. If there is not,
and the green LED beside Q5 is not on, please check further whether LED DS4
beside F4 on the fuse panel is on, or take down F4 to test whether it is burnt out
1) Check whether there is 0 ~ 10Vdc analog signals output from P51, if not,
check the control board carefully;
2) Check whether the values of S147 and S149 are set too low, if so, fix it by
increasing the setting value properly;
3) Check whether the external static pressure (ESP) is too high, if so, fix it by
optimizing the air channel and increasing the setting value properly
Liebert.PEX2 Series Air Conditioner User Manual
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94 Chapter 8 Troubleshooting
Symptom Potential causes Items to be examined or handled
EC fan cannot
be started
EC fan failure
Symptom Potential causes Items to be examined or handled
Power is not on (shutdown)
Compressor cannot
start
Contactor cannot close,
compressor cannot
start
Contactor closed, but
compressor cannot
start
Compressor stops after
running for 5min (1min
~ 5min settable). Or
contactor opens
Dual cooling/free cool
unit. When the
room/setting
temperature checked to
display refrigeration
requirement, but
without refrigeration
output within 10min, the
compressor will stop
running
HP protection
Power overloaded and MCB tripped
Circuit connection loosened
Compressor coils shorted
No demand for cooling output
High voltage switch action
Contactor failure
Circuit breaker disconnected
Compressor internal circuit breaker open
Refrigerant leaked, the LP switch cannot
close, or the pressure reading from the LP
sensor of the dual cooling unit is lower;
the reading is incorrect from the LP
sensor of the dual cooling unit
In compressor operation, the antifreezing
protection will be generated for shutdown
Condenser clogged
Temperature of input water is too high or
the water flow if too small (water-cooled)
Condenser system does not start
Too much refrigerant charging Check whether the subcooling degree is too high
Electric valve improperly set
(water-cooled)
1) Check whether the fans L1, L2 and L3 are power-off, phase failure or
undervoltage;
2) Check whether the analog signals output from P51 meet 0 ~ 10Vac
requirements;
3) Check whether the motor is clogged (overcurrent);
4) Check whether the motor is over temperature;
5) Hall failure;
If the problem is related to the first three points, the motor will run automatically
after fixing the problem;
If the motor is over temperature, switch off the fan till the motor cools down, and
recover it by switching on;
If the problem is Hall failure, contact the manufacturer for maintenance
Table 8-2 Troubleshooting of compressor and cooling system
Check the main power switch, fuse or circuit breaker and
the connection cable
Manual reset and check the average current
Fasten the connections
Check the motor winding and replace it if defects are
found
Check the iCOM controller state
Check the high voltage switch
Check the contactor, and check whether the 24Vac
voltage is between E1 and P32-10 (compressor 1) and
P32-12 (compressor 2) terminals
Check the circuit breaker and the contactor, and measure
the circuit voltage
Check the compressor coils. If the coils are open, they
will reset automatically after they cool down
1) Check the suction pressure;
2) Check the cable containing LP switch;
3) Check whether the LP sensor reading and actual
pressure meet ±0.3bar requirement (the HP sensor value
can be read from the SERVICE MENUS/DIAGNOSTICS,
which displays the absolute pressure)
Check the system and air channel to find out the reason
why LP is too low
Clean the condenser or BPHE;
Check the water system
For air-cooled series, check the condensing fan; for
water-cooled series, check water system. Check the
operation procedures
Check whether the LP sensor reading and actual
pressure meet ±0.6bar requirement (the HP sensor value
can be read from the SERVICE MENUS/DIAGNOSTICS,
which displays the absolute pressure)
Check whether the BPHE electric ball valve is normal
Liebert.PEX2 Series Air Conditioner User Manual
Page 100
Chapter 8 Troubleshooting 95
Symptom Potential causes Items to be examined or handled
Low discharge
pressure
The suction and
discharge pressures do
not change after startup
Low suction pressure or
liquid returned
Compressor too noisy
Compressor
over-temperature
Water flow too big or temperature of input
water too low (water-cooled)
Refrigerant leaked Locate the leakage point, repair it and add refrigerant
Fan speed controller of outdoor unit is
faulty, while the output voltage remains
100%, regardless of the change of
condensing pressure (air-cooled)
Compressor reversed or compressor
internal air tightness failed
Insufficient refrigerant in the system
Filter too dirty Replace the filter
Filter drier clogged Replace the filter drier
Improper superheating degree
Defective element of the thermal
expansion valve faulty
Improper air flow distribution Check the air supply and return system
Low condensing pressure Check the condenser
Belt slipped
The single source cooling unit configured
with FC fan, its dehumidification
electromagnetic valve is closed
ESP is too large, air flow reduction
Liquid returned
Lubricant loss Add lubricant
Fixture of compressor is not removed Remove the transportation fixture
Too high compression ratio
Too high suction temperature
Check the water system
If the fan speed controller is found faulty, replace it
If compressor is reversed, exchange any two L lines of
the compressor. If the compressor internal air tightness is
failed to recover, replace the compressor
Check for leakage. Seal the leaking point and add
refrigerant
Regulate by strictly following the adjusting procedures of
the thermal expansion valve
Replace the thermal expansion valve
Check the belt and make necessary adjustment or
replacement
Check the status of the dehumidification electromagnetic
valve when the system has no dehumidification
requirement. Examine whether there is 24Vac voltage
between P34-8 and E1, if there is not, it indicates that the
dehumidification electromagnetic valve is closed, you
should check the relevant cables of the electromagnetic
valve;
Check whether the air flow lose switch connection is
normal. Examine whether there is 24Vac voltage between
P36-7 and E1 after power-on, if there is not, you should
check whether the air flow lose switch is damaged
Check the ventilation duct or air channel, evaluate the
unit ESP again
Refer to the handling methods of
liquid returned
Check the settings of the HP switch and LP switch, and
make sure whether the condenser is clogged;
Check that the fans of the evaporator and condenser are
normal
Regulate the expansion valve or add proper amount of
refrigerant
Low suction pressure or
Liebert.PEX2 Series Air Conditioner User Manual
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