Liebert ITR Dehydration/Leak Test, Low Pressure Cut Out High Pressure Cut Out 360

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Air-Cooled Models

Dehydration/Leak Test

1.Make sure unit is OFF. Open all disconnect switches and pull all fuses except control fuses. On units supplied with circuit breakers, open all breakers except for the transformer.

2.Add a jumper to the Fan Safety Switch between Common and Normal Open and disconnect the wire connected to the Normally Closed. Turn unit disconnect ON. (Fan operation not required.)

NOTE

The above allows the technician to use unit 24 VAC power and controls to open liquid line solenoid valve(s) and hot gas bypass solenoid valve(s) for the dehydration process. If no power is at the unit disconnect, the technician is to use a separate 24 VAC source rated at 75 VA and connect to the system liquid line solenoid valve(s) and hot gas bypass solenoid valve(s) directly.

3.Connect refrigeration gauges to the suction and discharge service valves of the compressor and open.

4.Attach a “jumper” hose from the Rotalock fitting on the outlet of the receiver and the Schrader fitting on the liquid header of the condenser. Front seat the Rotalock valve approximately two turns.

5.To energize the liquid line solenoid valve(s) through the control system, set the temperature setpoint (see operation manual) to 60°F (15°C) and set the % relative humidity setpoint higher than the conditioned room ambient to ensure that solenoid valves and hot gas bypass valves are open during the dehydration process.

6.Pressurize system circuit(s) to 150 PSIG (1034 kPa) by using dry nitrogen with a trace of refrigerant. Check system for leaks with suitable leak finder.

7.After completion of leak testing, release test pressure (per local code) and pull a vacuum on the system.

8.After 4 hours, check pressure readings and, if they have not changed, break vacuum with refrigerant. Pull a second and third vacuum of 250 microns or less. Recheck pressure after 2 hours.

3.5.4Charging

1.Make sure unit is OFF. Open all disconnect switches and, on units supplied with circuit breakers, open all breakers. Replace all fuses for the Fan and Compressors or close breakers.

2.Remove jumper on the Fan Safety Switch and reconnect the system wire connections. Ensure that all operational components are clear of debris. Turn unit ON. (Fan operation is required.) Check the evaporator fan for proper rotation and correct if necessary.

3.Connect the refrigerant gauge charging hose to the drum of refrigerant and to the suction and discharge service valves of the compressor(s).

4.Calculate the amount of charge for the system. Weigh in as much of the system charge as possible. Refer to the unit, condenser and refrigerant line charge tables.

5.Set the control temperature setpoint (see operation manual) to 60°F (15°C) and set the % relative humidity setpoint higher than the conditioned room ambient to ensure that solenoid valves and hot gas bypass valves are open during the charging procedure. You may have to bypass the

LP Switch (low pressure switch) to start the compressors and stop short cycling. Reset the Head Pressure switch(es) if open.

6.Add refrigerant (R407C liquid or R22 vapor per unit nameplate) to the suction side of the compressor until there is sufficient pressure to energize the low pressure switch.

NOTE

When adding refrigerant to an operating system, it may be necessary to add the refrigerant through the compressor suction service valve. Because the refrigerant leaving the refrigerant cylinder must be in a liquid state, care must be exercised to avoid damage to the compressor. It is suggested that a sight glass be connected between the charging hose and the compressor suction service valve. This will permit adjustment of the cylinder hand valve so that liquid can leave the cylinder while allowing vapor to enter the compressor.

Then you may remove the manual bypass you applied earlier.

7.Charge the unit until the proper charge is weighed in.

Table 10 Refrigerant control settings psi (kPa)

Low Pressure Cut Out

Low Pressure Cut In

High Pressure Cut Out

 

 

 

20 (137.9)

65 (448.2)

360 (2482)

 

 

 

22

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Contents Liebert Challenger ITR Page Table of Contents Split System Models Chilled Water ModelsR407C Refrigerant Figures Tables System Descriptions Remote Sensor Installation Location Room PreparationEquipment Inspection Location ConsiderationsUnit shipping weights Handling With SkidRemoval of Skid Domestic Export Model Lb kg 50Hz Models 60Hz ModelsCabinet dimensions Unit WeightSL-11897 Drain Line Piping ConsiderationsPiping connection size Piping Outlet Locations Piping connections for split system fan coil units Piping connections for water/glycol and Glycool units Piping connections for chilled water self-contained units Electrical Connections Electrical connectionsBalancing the Air Distribution Plenum InstallationDucted Applications Checklist for Completed Installation Condenser Location Line VoltageLow Voltage Lee-Temp/Flood Back Head Pressure Control CondensersAir-cooled condenser statistics Refrigerant Piping Recommended line sizes OD copper inches23 & 33 kW 067A 065A Equivalent Length Hot Gas Line Liquid LineFan Speed Control Systems Materials SuppliedEquivalent lengths feet for various pipe fittings Condenser refrigerant per serial tagDehydration/Leak Test Single Circuit Shown Refrigerant control settings psi kPa Lee-Temp/Flood Back Head Pressure Control SystemsCharging PipingMaterials Supplied Low Pressure Cut Out High Pressure Cut Out 360 Single Circuit Shown Condenser Water-cooled general arrangement Water Regulating Valve Adjustment Testing Valve FunctionWater Regulating Valve Water Regulating Valve Manual FlushingDrycooler Location Drycooler InstallationPump and Drycooler Room dew point temperatures Glycol PipingExpansion Tanks, Fluid Relief Valves and Other Devices Dry Bulb Wet Bulb Relative Dew Point HumidityIndoor unit glycol volume approximate gallons liters max Volume in standard Type L copper pipingFilling Instructions Preparing the System for FillingEthylene glycol concentrations Glycol Solutions@ 50F 10C Filling the System For expansion tank dimensions, see on 43-9/16 110 5mmSee Note 30-1/4 483mm 43-3/16 1097mmMounting hole dimensional data Drycooler dataGlycol pump data Pump Pump Suction Pump Discharge ConnectionGlycol general arrangement Glycool general arrangement Glycol Regulating Valve Adjustment Glycol Regulating ValveChilled Water Models Air-Cooled Condensing Units Water/Glycol-Cooled Condensing UnitsRefrigerant Loop Recommended refrigerant lines R22 or R407C sizes OD copper Unit refrigerant chargeLine coupling sizes Evaporator Evaporator Condensing UnitQuick Connect Fittings Unit Dimensions See Table Outdoor Air-Cooled Condensing UnitsPFH067A-L Outdoor air-cooled condensing unit-top air discharge models See Table36-1/4 38-1/2 Piping and electrical connections top air discharge152 Electrical field connections, prop fan condensing module SL-11081 PG 8AInstalling the Indoor Condensing Unit Model Net Weight 60 Hz 50 Hz Lb kg MC65A MC64ACentrifugal Air-Cooled Condensing Units Indoor centrifugal condensing unitDucting Airflow CFM CMHCentrifugal air-cooled condensing unit dimensional data AIR Cooled Water Cooled Regulating Valve Adjustment and Testing Water and Glycol-Cooled Condensing UnitsPiping Considerations Condenser Water RequirementsWater/glycol-cooled condensing unit dimensions WATER/GLYCOL Temperature Gauge Pressure Psig KPa R407C RefrigerantCalculating Subcooling Temperature Pressure Gauge Psig KPaExample Ne t ItiTi n That

ITR specifications

The Liebert ITR is an advanced precision cooling unit designed to maintain optimal temperature and humidity levels in mission-critical environments. Engineered for high-performance applications, it is particularly suitable for data centers, telecommunications facilities, and other spaces that require precise climate control to ensure uninterrupted operation of sensitive equipment.

One of the main features of the Liebert ITR is its modular design. This allows for scalability and flexibility, enabling users to customize the system based on their specific cooling needs. The unit can be configured in various sizes and cooling capacities, making it suitable for both small server rooms and large data centers. This adaptability is crucial for organizations that anticipate growth and require an efficient cooling solution that can evolve with their infrastructure.

The Liebert ITR incorporates state-of-the-art technologies to enhance performance and energy efficiency. Among these technologies is the use of a variable speed compressor that adjusts its speed based on the cooling load. This capability not only improves energy efficiency but also significantly reduces operational costs by minimizing electricity consumption when cooling demands fluctuate.

Additionally, the unit features advanced control systems that provide intelligent monitoring and management of temperature and humidity levels. These systems can integrate seamlessly with building management systems (BMS) and can be operated remotely, providing users with real-time insights into the performance of the cooling system. Such connectivity ensures quick identification and resolution of potential issues, thereby reducing downtime and maintaining optimal conditions for critical equipment.

The Liebert ITR utilizes eco-friendly refrigerants, contributing to reduced environmental impact while ensuring compliance with regulatory standards. The unit's design also emphasizes reliability, featuring robust construction and redundant components that enhance longevity and minimize the likelihood of failures.

Furthermore, the Liebert ITR is equipped with advanced filtration systems that maintain air quality by reducing particulate matter and contaminants, ensuring that the atmosphere within data centers is not only cool but also clean—critical for the longevity of sensitive electronic equipment.

Overall, the Liebert ITR is characterized by its innovative design, energy-efficient operation, and comprehensive control capabilities, making it an ideal choice for businesses looking to safeguard their critical infrastructure from overheating and humidity. As climate control becomes increasingly important in the digital age, the Liebert ITR stands out as a reliable solution for maintaining optimal environmental conditions.
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