Vertiv Liebert DM Series User manual

Liebert DM Series
Precision Air Conditioner
User Manual

Copyright by Vertiv Co. Ltd.
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Vertiv Co. Ltd.
Notice
The purchased products, services, and features are stipulated by the contract made between
Vertiv Co., and the customer. All or part of the products, services, and features described in this
document may not be within the purchasing scope or the usage scope. Unless otherwise
specified in the contract, all statements, information, and recommendations in this document are
provided "AS IS" without warranties, guarantees or representations of any kind, either express or
implied. The information in this document is subject to change without notice. Every effort has
been made in the preparation of this document to ensure the accuracy of the contents, but all
statements, information, and recommendations in this document do not constitute a warranty of
any kind, express or implied.
Vertiv Co., Ltd.
•China
Website: www.vertivco.com.
E-mail: [e-mail].
Customer service hotline: [phone]
•Asia Pacific
Homepage: www.vertivco.com.
E-mail: [e-mail]
For Technical Support, users may contact the nearest Vertiv Co. local sales office or service
center.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

Purpose of the Document
This document applies to the Liebert DM series of precision air conditioners and cooling solutions
which maintain an optimal environmental control mainly for testing laboratories, data center rooms
and similar technological ecosystems at minimal operating costs.
This document explains the product description, installation measures, operational workflow,
maintenance, and detailed aspects from the user perspective. The figures used in this document
are for reference only.
Please read this manual carefully before installing, maintaining, and troubleshooting, especially
the warning information in the manual
Styling used in this Guide
The styles used in the manual will be defined as mentioned in the following table:
Situation
Description
Warning/Danger/Caution
The Warning/Danger/Caution note
indicates a hazardous or potentially
harmful situation that can result in death
or injury. It also indicates instructions that
need to be adhered to, failing which may
result in danger and safety issues thereby
having an adverse effect on the reliability
of the device and security. Even for
practices not related to physical injury, the
content under the Warning heading is
used for precautions which need to be
taken which, otherwise, could result in
equipment damage, performance
degradation, or interruption in service.
Note
The Note section indicates additional and
useful information including tips and
tweaks. It also calls attention to best
practices and industry-best protocols that
are standardized and help make maximum
utilization of the resources at hand.
Helpful information related to the
mainstream stuff also comes under the
Note heading helping the users get to
grips with the definitions, concepts, and
terminologies used in the manual.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

Version History
Issue
Revision
Changes
1
1.0
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Safety Precautions and Measures
The important safety precautions and measures that should be followed during the installation and
maintenance of the Liebert DM models are described in the following sections.
Read the manual prior to installation and operation of the unit. Only qualified personnel should
move, install, or service this equipment.
The user reads and takes into account all the precautions, compliance, and safety measures before
working on the equipment. The unit control must be used exclusively for the purpose which it is
intended for; the manufacturer takes no liability for incorrect use or a modification to the unit
control.
Adhere to all the Warnings and Cautionary measures included in the manual.
Please read this manual carefully before installing, maintaining and troubleshooting; especially the
Warning/ Danger/ Caution information in the User Guide. Apart from the User Guide, also pay
attention to the warning labels on the unit and its components.
This manual is retained for the entire service life of the machine. The user must read all the
precautions, danger, warnings, and cautionary measures mentioned in the manual prior to
carrying out any operations on the machine. Each machine is equipped with an electric
insulation which allows the users to work in safe conditions. The main switch is positioned on
the electrical panel cover; Open the right door to access it. Before any maintenance operation,
switch off the machine with this electronic insulation device in order to eliminate risks such as
electrical shocks, burns, automatic restarting, moving parts, and remote control. The panel key,
supplied along with the unit, must be kept by the personnel responsible for the maintenance.
The protective covers can be removed after the electric power has been cut off by opening
the main switch.
In the following section, take a look at the various cautionary measures and warnings that need to be read
carefully prior to installing or operating the system.
Disconnect the local and remote power supplies prior to working with the unit.
Prior to the installation process, read all the instructions, verify if all the parts are in place, and check the
nameplate to ensure that the voltage matches the utility power that is available for that unit.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

The controller doesn’t isolate power from the unit even in the Off mode. Moreover, some internal
components require and receive power even during the Off mode.
If the unit door is open while the fans are operating, the airflow may result in abrupt slamming of the door
resulting in injury. Another aspect is the presence of small objects in the fans bay which may result in object
ejection during the fan start-up and there is a probable risk of being hit by these objects leading to grievous
injury as well as causing equipment damage.
The unit contains fluids and gasses under high pressure. Therefore, the pressure should be relieved
before working with the piping.
Various components such as compressors, refrigerant discharge lines, and humidifiers are extremely hot
during the unit operation. Therefore, allow sufficient time for the unit to cool down before working with the
unit cabinet. Handle the unit with extreme caution and wear safety equipment such as protective gloves,
safety shoes, and arm protection while working with the hot compressors, discharge lines, and reheats.
There is a risk of leaking water that can cause damage to the equipment as well as the building. There
should be an effective water drain connection and facilities. Installation should be precise. Implementation
of the application and service practices should be suitable and fault-free. Not complying with these norms
will result in water leakage from the unit. Water leakage can result in massive damage and loss of critical
equipment in the hosting ecosystem. Therefore, care should be taken to ensure that the unit must not be
located directly above any equipment that could sustain damage due to water and excessive moisture.
Using a leak detection system for unit and system supply lines are recommended by Vertiv Co.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

TABLE OF CONTENTS
PART I - GENERAL INFORMATION
1 Introduction ......................................................................................................................................................................................... 2
1.1 Model Nomenclature....................................................................................................................................................... 3
1.2 Basic Performance Parameters .............................................................................................................................. 3
1.3 Product Description ........................................................................................................................................................ 4
1.3.1 Compressor ......................................................................................................................................................... 5
1.3.2 Evaporator ........................................................................................................................................................... 6
1.3.3 Thermal expansion valve (TXV) ......................................................................................................... 6
1.3.4 Micro-processing Controller.................................................................................................................. 7
1.3.5 Strainer .................................................................................................................................................................. 7
1.3.6 Filter ......................................................................................................................................................................... 8
1.3.7 Centrifugal Fan................................................................................................................................................. 8
1.3.8 Condenser ........................................................................................................................................................... 8
1.3.9 Sight Glass .......................................................................................................................................................... 9
1.3.10 Infrared Humidifier ..................................................................................................................................... 9
1.4 Optional Components ................................................................................................................................................ 10
1.4.1 Electric Heater ............................................................................................................................................. 10
1.4.2 Remote Monitor ........................................................................................................................................... 10
1.4.3 Energy-Saving Card ...................................................................................................................................11
1.4.4 Power SPD..........................................................................................................................................................11
1.5 Working Conditions................................................................................................................................... 11
1.5.1 Operating Environment ............................................................................................................................ 12
1.5.2 Storage Environment ................................................................................................................................ 13
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

1.5.3 Refrigerant Charging Requirement ................................................................................................ 13
PART II - INSTALLATION
2 Installation .......................................................................................................................................................................................... 15
2.1 Pre-Installation ................................................................................................................................................................. 15
2.1.1 Transportation and Movement ........................................................................................................... 15
2.1.2 Unpacking..........................................................................................................................................................16
2.1.3 Inspection .......................................................................................................................................................... 17
2.2 Installation Preparation (Site Preparation) ................................................................................................. 17
2.2.1 Equipment Room Requirement.......................................................................................................... 17
2.2.2 Installation Space requirements .......................................................................................................18
2.2.3 Installation Tools.........................................................................................................................................20
2.3 Mechanical Installation .............................................................................................................................................. 21
2.3.1 System arrangement during installation..................................................................................... 21
2.3.2 System Installation Mode ..................................................................................................................... 23
2.3.3 Product Dimensions ................................................................................................................................. 24
2.3.4 Outdoor unit ................................................................................................................................................... 25
2.3.5 Indoor Unit Installation ........................................................................................................................... 26
2.3.6 Outdoor Unit Installation ...................................................................................................................... 27
2.3.7 Procedure ......................................................................................................................................................... 27
2.3.8 Piping for AC Unit ...................................................................................................................................... 29
2.3.9 Installation Notes Of Connector ..................................................................................................... 30
2.3.10 Required Pipe Connections............................................................................................................... 31
2.3.11 Connecting Refrigerant Pipe ............................................................................................................. 31
2.3.12 Pipe connector position ...................................................................................................................... 33
2.3.13 Connecting discharge pipe ............................................................................................................... 34
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

2.3.14 Connecting liquid pipe ......................................................................................................................... 34
2.3.15 Connecting Drain Pipe Of Indoor Unit ...................................................................................... 35
2.3.16 Connecting Humidifier Water Supply Pipe (If Applicable) ........................................ 35
2.3.17 Removing Transportation Fastener And Vibration Absorber ................................. 35
2.3.18 Adding Refrigerant For Long Pipe System ........................................................................... 36
2.3.19 Check List ...................................................................................................................................................... 37
2.4 Electrical Installation .................................................................................................................................................. 38
2.4.1 On-site Wire connections ..................................................................................................................... 38
2.4.2 Installation Notes ....................................................................................................................................... 38
2.4.3 Connecting Power Cable Of Indoor Unit ................................................................................... 39
2.4.4 Connecting Power Cable Of Outdoor Unit ............................................................................. 40
2.4.5 Connecting Control Terminals ......................................................................................................... 41
2.4.6 Connecting Monitoring Port Cable ............................................................................................... 45
2.4.7 Connecting Energy-Saving Card .................................................................................................... 45
2.4.8 Checklist ........................................................................................................................................................... 47
PART III - SYSTEM OPERATION & GENERAL MAINTENANCE
3 System Operation ......................................................................................................................................................................... 51
3.1 Start-Up Inspection ....................................................................................................................................................... 51
3.2 Micro-Processing Controller................................................................................................................................. 52
3.2.1 Features ............................................................................................................................................................. 52
3.2.2 Appearance ..................................................................................................................................................... 52
3.2.3 LCD Screen ..................................................................................................................................................... 53
3.2.4 Control Buttons ........................................................................................................................................... 53
3.2.5 Control Buttons Operation Example ............................................................................................ 54
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

3.2.6 ON Screen ........................................................................................................................................................ 55
3.2.7 Language Screen ........................................................................................................................................ 55
3.2.8 Normal Screen .............................................................................................................................................. 56
3.2.9 Password Screen ........................................................................................................................................ 56
3.3 Function Testing ........................................................................................................................................................... 57
3.3.1 Cooling ................................................................................................................................................................ 57
3.3.2 Heating............................................................................................................................................................... 58
3.3.3 Humidifying .................................................................................................................................................... 58
3.3.4 Dehumidifying .............................................................................................................................................. 58
3.3.5 Checking Refrigerant Charge Capacity of Low-Temp Outdoor .............................. 58
3.4 Micro-Processing Controller Menu Options ............................................................................................. 59
3.4.1 Main Menu........................................................................................................................................................ 59
3.4.2 Alarm Menu ................................................................................................................................................... 60
3.4.3 Set Points ......................................................................................................................................................... 63
3.4.4 System Status............................................................................................................................................... 63
3.4.5 System Menu .................................................................................................................................................66
3.4.6 Help Menu ....................................................................................................................................................... 67
3.4.7 Display Set .......................................................................................................................................................68
4 General Maintenance ................................................................................................................................................................69
4.1 Electric Inspection ........................................................................................................................................................ 70
4.2 Indoor Unit Maintenance ........................................................................................................................................ 70
4.2.1 Filter ...................................................................................................................................................................... 70
4.2.2 Fan ......................................................................................................................................................................... 72
4.2.3 Drain Pipe......................................................................................................................................................... 72
4.2.4 Heater ................................................................................................................................................................. 72
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

4.2.5 Humidifier ........................................................................................................................................................ 72
4.2.6 Power SPD ....................................................................................................................................................... 74
4.2.7 Thermal Expansion Valve..................................................................................................................... 76
4.2.8 High-Pressure Switch And Low-Pressure Switch ............................................................. 76
4.2.9 Compressor .................................................................................................................................................... 77
4.3 Outdoor Unit Maintenance .................................................................................................................................... 78
4.3.1 Refrigeration System................................................................................................................................ 78
4.3.2 Air-Cooled Condenser ............................................................................................................................ 78
4.3.3 Low-Temperature Unit Of Low-Temp Outdoor Unit ....................................................... 78
4.4 Maintenance Inspection Checklist .................................................................................................................. 79
4.5 Troubleshooting .............................................................................................................................................................81
APPENDIX 1 - Crcuit Diagrams .................................................................................................................................... 86
APPENDIX 2 Menu Structure ...................................................................................................................................... 87
APPENDIX 3 Parameter Setting Table................................................................................................................... 88
APPENDIX 4 - RDU-Cooling AC Single-Unit Manager Software Introduction ............................91
APPENDIX 5 - Hazardous Substances List........................................................................................................94
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual

PART I
GENERAL INFORMATION
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 1

1 Introduction
The Liebert DM series is the next generation series of small air conditioners that provide precise
environmental control. The Liebert DM models are the latest in the long line of modern enterprise-
grade products from the Liebert family. Incorporating the high standards associated with the Liebert
name, the DM series utilizes the latest technology, system components, and a streamlined
manufacturing process.
Liebert DM air conditioners are products that are specifically created and designed for cooling the
electrical devices. It is applicable to equipment rooms, computer rooms, and similar ecosystems
which call for a high degree of accuracy and precision in maintaining the ambient temperature. It
addresses the needs and challenges associated with such applications and setups. It caters to
sensitive applications which need a suitable environment for optimal performance. Therefore, care
should be taken while testing these sensitive products or maintaining a favorable environment for
mission critical equipment, as even a slight deviation may lead to inaccurate results. Precision Air
Conditioning must not only keep room conditions within a specific range but also must have the
precision to react quickly to a drastic change in heat load and prevent wide temperature fluctuations.
The DM air cooled AC unit is packed with features such as high reliability, high sensible heat ratio,
and large airflow. The unit is an air-cooled single cooling system and configured with DC Speed
Regulation back- inclined centrifugal fan.
Packed with a host of features, it lowers the sound emissions significantly and thereby reduces the
noise pollution. It is a top-notch system that adheres to the standard in Precision Air Cooling in
terms of energy-efficiency, space requirements, and reliability.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 2

Figure 1-1 shows the appearance of various models in the Liebert DM series:
Figure 1-1
1.1 Model Nomenclature
The model nomenclature of the Liebert DM AC is shown in Figure 1-2:
Figure 1-1
1.2 Basic Performance Parameters
The basic performance parameters of the Liebert DM AC are given in Table within
Listing 1.1.
Listing 1.1
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 3

Model
Nominal
cooling
capacity
(kW)
Power
(kW)
Annual
energy
efficiency
ratio
Heating
capacity[1]
(kW)
Humidification
capacity [2]
(kg/h)
DME07M**5
6.85
2.36
2.9
3.2
1.5
DME12M**5
11.9
4.1
2.9
3.2
1.5
Note:
[1]: The heating capacity is only for the models with heating function;
[2]: The humidification capacity is only for the models with humidification function
1.3 Product Description
The Liebert DM AC unit is a comprehensive system that includes all the main functions fundamental to
precision cooling units such as cooling, humidification, dehumidification, re-heating, air filtration,
condensation management, temperature and humidity control, alarm functions and compatibility with
data communications. Liebert DM AC is designed to comply with mission-critical requirements and
ensure that servers are maintained at the correct temperature and humidity levels.
Figure 1-3 shows the various components and their respective locations:
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 4

Figure 1-2
Listing 1.2
Item
Description
Item
Description
1
Heater
2
Evaporator
3
Centrifugal Fan
4
Compressor
5
Infrared Humidifier
6
Microcontroller Display
7
Filter
In the following sections, take a look at the list of components used in the Liebert DM AC series.
1.3.1 Compressor
The Liebert DM AC series models comprise of a scroll compressor which has a host of promising
features such as low operating noise, less vibration and high reliability. Its compactness, smooth
compression with scroll operation and high energy efficiency ratio makes it an ideal compressor to
bank on for the DM series.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 5

Figure 1-3 shows the image of a compressor.
Figure 1-4
1.3.2 Evaporator
Heat exchanger design and appropriate air distributions are important factors that determine optimum
performance. The Evaporator used in the Liebert DM AC models consists of a fin-tube heat exchanger
for higher efficiency. The sophisticated design of the distributor ensures that the refrigerant is
distributed evenly in each loop, thereby improving the effectiveness of the heat exchanger.
Figure 1-5 shows the image of an Evaporator.
Figure 1-5
1.3.3 Thermal expansion valve (TXV)
The thermal expansion valve controls the amount of refrigerant flow into the evaporator thereby
controlling the superheat at the outlet of the evaporator. Liebert DM consists of a thermal expansion
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 6

valve with external equalizer type. It collects temperature and pressure signals at the same time to
accurately regulate the refrigerant flow.
Figure 1-5 depicts the image for the TXV:
Figure 1-6
1.3.4 Micro-processing Controller
The Controller adheres to the latest and highly advanced PID regulation technology. It provides a
simple operation user interface with multi-level password protection, self-recovery upon power failure,
high-voltage & low-voltage protection, phase loss protection, automatic phase-sequence switching
upon anti-phase and rotate speed control of the outdoor fan. The expert-level fault diagnoses system
can automatically display current fault information to facilitate equipment maintenance by
maintenance personnel.
Figure 1-7 depicts the panel of the Microcontroller:
Figure 1-7
1.3.5 Strainer
The Strainer filters the impurities generated during long-term system operation and ensures normal
system operation.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 7

1.3.6 Filter
Moisture can have an adverse effect on the operation and life of a system in the refrigeration cycle.
To counter that effect, Filter-driers are used to filter out particles, and remove and hold moisture to
prevent it from circulating through the system. The Liebert DM AC consists of nylon filter material
with big mesh. The filter features compact structure and easy maintenance. It can be washed
repeatedly.
1.3.7 Centrifugal Fan
Centrifugal fans are rigid and strong metal fans. Its axial flow blades help in reducing the noise. The
single-phase motor with high performance is customized based on the power grid of base stations, so
it can work over a wide voltage range with high reliability. It features large airflow, long blowing
distance, direct driving and easy maintenance.
Figure 1-8 depicts the image for the Centrifugal Fan:
Figure 1-8
1.3.8 Condenser
The Liebert range of air-cooled condensers offers many advantages, including sharp design, antirust
aluminum cabinets, low sound levels, and reliable operations over a wide range of ambient conditions.
Figure 1-9 depicts the image of a condenser:
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 8

Figure 1-9
1.3.9 Sight Glass
The sight glass is a utility for observing the refrigerant state; specifically the moisture content of the
system. If the moisture content exceeds the levels of defined standards the color changes, thereby,
indicating irregularity in the moisture content.
1.3.10 Infrared Humidifier
The infrared humidifier consists of infrared humidifier lamp, water injection valve, humidifying water
dish, temperature alarm protection devices and water level alarm device.
The infrared humidifier in the Liebert DM series provides quicker and more responsive operation
which is quite important for mission-critical applications. These humidifiers reduce the dependency of
water quality and simultaneously achieve full capacity in quick time using almost any water quality.
Vertiv | Liebert DM Series Precision Air Conditioner | User Manual 9