Daikin GCU2020PXB1 Guide

Hubbard Products Ltd. 1-7 Bluestem Road,
Ransomes Europark, Ipswich, Suffolk, IP3 9RR UK
Tel: [phone]
email: [e-mail]
www.hubbardproducts.com
Hubbard Products Ltd
Hermetic R744 Condensing Units
Model Number:
GCU2020PXB1
ESIE20-02
Installation, Commissioning and
Maintenance Manual
Page 1 of 179
Copyright HPL March 2021
P41135 Rev 03

Hubbard Products Ltd. 1-7 Bluestem Road,
Ransomes Europark, Ipswich, Suffolk, IP3 9RR UK
Tel: [phone]
email: commerci[email protected]m
www.hubbardproducts.com
CONTENTS
1
EC Declaration of Conformity
2
Installation, Commissioning and maintenance
instructions
3
Material Safety data Sheets
4
Wiring Schematics
5
Pipework Schematics (P&ID)
6
Carel PR300T CO2 Controller manual and factory
settings
7
ABB Inverter non-default settings
8
Pressure & Enthalpy Diagram
9
Commissioning Form
10
ECO Design
11
Evaporator Installation Guide
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Hubbard Products Ltd. 1-7 Bluestem Road,
Ransomes Europark, Ipswich, Suffolk, IP3 9RR UK
Tel: [phone]
email: commerci[email protected]m
www.hubbardproducts.com
1. EC Declaration of Conformity
Model: GCU2020PXB1
Part Number: A10145-02M
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Hubbard Hermetic Rotary R744 Units
Installation, Commissioning and Maintenance
Manual
Model No.: GCU2020PXB1
ESIE20-02
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Contents
1. Safety recommendations
2. Storage
3. Description of the unit
4. Application
5. Handling
6. Post Transport Checks
7. Overall Dimensions
8. Serial plate Information
9. Installation Spacing
10. External Pipe and Electrical Connections
11. Basic Component layout
12. Mechanical Safety of the system
13. Commissioning and Maintenance
14. Service and Maintenance
15. Maximum Refrigerant Charge
16. Estimation of Refrigerant and Oil Charge
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These pages contain important safety information. Please read carefully before commencing any work on the
equipment to which the instructions refer.
It is assumed that installation, commissioning, service and maintenance activities must only be undertaken only by
competent personnel who have been trained for the activity. They should be familiar with this type of equipment
and the handling of refrigerants and their disposal.
1. Safety recommendations
When installing and using the unit please follow the recommendations listed here below.
•Installation shall be carried out in strict compliance with the diagrams and instructions supplied by the
manufacturer.
•Damages due to improper connections are excluded.
•The electric system available where the unit is installed shall meet the relevant standards in force.
•Maintenance shall be effected by trained personnel or by the manufacturer according to the provisions as per
EN378.
WARNING
Use safety gloves to protect your hands from possible cuts.
The user is strongly recommended to contact the manufacturer before attempting any intervention on the unit and
any use not corresponding to the manufacturer’s indications (in particular as for the field of application) and to
enquire about the possible dangers and contra-indications connected with an improper use of the machine.
•The unit shall be used following these instructions and sticking to the destination of use indicated by the
supplier. Any incorrect use can result in damages to the unit and represents a serious danger for people’s
health.
ATTENTION
The unit is not suitable for working in explosive environments.
Therefore the use of the unit in an explosion-dangerous atmosphere is absolutely forbidden.
When maintenance requires operations on the cooling circuit, drain the system and let it reach the
atmospheric pressure. Oil residuals left in the refrigerant receiver should be recovered and disposed of by
specialized firms, specially authorized by the national regulations in force.
ATTENTION
The unit is not suitable for working in salty environments. In such a case protect condenser
and evaporator with appropriate means.
•Only use refrigerant and oil as specified on the serial plate and this manual.
•No modifications or changes in circuit or components (such as: welding on compressor body, on refrigerant
receiver wall or on refrigerant separator wall) are allowed.
•Sight glasses, minimum level indicators and flanged couplings are secured to the receiver or the separator by
means of demountable fixing elements. As a rule, gaskets resist pressure, temperature and fluid stresses.
When fixing elements include gaskets (for example glass windows and flanges) however, reduced tightness
and bedding of gaskets can not be excluded due to their features; for this reason tighten them before and
possibly after starting. Driving torques can be different. On sight glasses (mounted on refrigerant receiver) use
a dynamometric wrench, otherwise the steel edge could be excessively loaded and cause glass breakage.
•Any official registration necessary for pressure appliances and repeated tests shall by governed by the laws
and regulations in force in the Country where the unit is installed. Compliance with laws, regulations and with
the technical instructions specified above falls within the manager’s responsibility.
•The final user shall protect the unit from external fire dangers.
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2. Storage
Equipment should be stored, prior to installation, in warm, dry conditions, free from dust, vibration and extremes
of temperature and humidity.
3. Description of the unit
Hubbard CO2 hermetic rotary series includes air-cooled condensing units. They consist of:
1. Condensing unit placed outside the cold room;
2. Electric control panel placed on the condensing unit.
4. Application
Under no circumstances must the equipment be used for any purpose other than that for which it
was specifically designed.
The equipment must be located on, and secured to a solid level base or framework designed for the purpose.
**Anti-vibration pads/feet are strongly recommended.
Access must be provided to allow safe working for both installation and servicing of all electrical and refrigeration
components. A safe exit path must be provided in the event of a mishap. During installation, the space must be
adequately ventilated to remove any potentially toxic/asphyxiating/explosive gases that may otherwise build up.
All pipework connected to the equipment must be adequately supported and all electrical components and supplies
connected to the equipment must conform to IEE regulations.
Refer to the individual electrical drawings supplied width the equipment for details of the electrical circuitry.
Extreme care should be exercised when opening any part of the refrigerant pipework to atmosphere for the
purpose of connecting pipework etc. The systems contain a positive pressure of inert gas, when despatched,
which will be released upon any breach of the equipment's pipework or pressure vessels.
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5. Handling
The unit shall be handled by appropriate lifting and transport means. An appropriate risk assessment should be
undertaken by a suitably qualified person before attempting to move or lift the equipment.
Make sure that no one is in transit in the operating area of the lifting/ transport means to
prevent any possible accidents to people.
If the unit is in a wooden case or crate, sling the packing properly before handling it.
Lifting speed shall be such as not to make the packed unit oscillate dangerously and
possibly fall.
6. Post Transport Checks
On siting the unit, we recommend the security of all electrical connections is checked, and system
flanges, rotalock valves, and flexible connections are secure. Where flexible hose lines are used please
ensure that the outer material is not subject to rupture due to contact with other surfaces.
Before initial operation we recommend that crankcase heaters are operated for 24 hours prior to
compressor operation to ensure correct lubrication properties are provided.
The units are factory tested including leak, pressure and electrical test – not running test. Anyway, is
highly recommend a further pressure test after transport and positioning to help prevent leakage in
operation. Pressure testing should be carried out according to your companies test procedures and
where applicable in accordance current P.E.D. recommendations, F-gas regulations and your customers
requirements.
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7. Dimensions and weights:
Models: GCU2020PXB1
7.1 Packaged Unit
7.2. Unit Dimensions
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7.3. W eights
Models: GCU2020PXB1
Packaged weight: 175 kg
Unit Dry weight: 151 kg
8. Serial Plate Information
The unit is supplied with necessary warning and attention plates. Serial plate is supplied with the weight of
the unit and other information as showing below.
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9. Installation spacing
Below picture shows the recommended spacing aroung the unit for operational, service and maintainence
purposes. Respect minimum spacing from walls as showing below.
ATTENTION
Before connecting the unit make sure that mains voltage and frequency correspond to
the values shown in the data plate. Voltage tolerance: +/- 10% compared to nominal
value.
10. External Pipe and Electrical connections
Liquid and Suction Line positions are shown as below. Both liquid and suction line are sealed to avoid any moister
entering the pipes. The unit is delivered with positive pressure, please make sure that you release pressure before
cutting the pipes.
Pipe Sizes:
GCU2020PXB1 :
Suction Line: 3/8’’ Liquid Line: 3/8’’
Mains electrical supply should be connected by drilling the cover plate as shown below. Secure main cable and
avoid scratches on mains cable. Fit M20 gland is recommended.
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The incoming three phase is connected to the main isolator as shown below.
For GCU2020PXB1 unit an incoming cable size of not less than 1.5 mm2is recommended. However, cable run and
voltage drop need to be consinder.
10.1 Recommends for liquid & suction pipework
It is really important to ensure a good oil return on the compressor. Suggested connections for suction and liquid
line are shown below.
Industry recognised design standards for pipework sizing are to be followed. Horizontal and vertical (riser) suction
pipework sizing during full and part load conditions require design to ensure sufficient oil recovery and return to
unit
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11. Basic component layout
12. Mechanical Safety of the system
Pressure relief valves and pressure switches are installed on the unit accordingly to EN 378. Pressure relief valves
are rated as below:
Max Allowable Pressures (PS):
•Intermediate Pressure (Liquid receiver)…………………………….. Rated 90 bar
Max Allowable Temperatures (TS): -45°C to +130°C
All the safety valve discharge vents on the condensing units are facing downwards in the compartment behind the
gas cooler fan.
•Pressure relief valves are preset to discharge at a set pressure. No attempt should be made to adjust this
setting or to check the setting by discharging the valve. Valves should be removed before testing to a
value in excess of 80% of the valve setting.
•Should the need to replace a valve arise, this can be achieved by shutting off the faulty valve by either
removing the system charge on assemblies fitted with single relief valves or via a dual shut off valve
assembly in which the pressure relief valve is mounted.
•Relief valves that have been found to have discharged refrigerant should be replaced as positive sealing
after discharge is not guaranteed.
•After maintenance a leak test is recommended to avoid any unexpected leaks occur during maintenance
process.
•Inspect the valves and replace according to PED and relevant regulations.
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13. Commissioning and Maintenance of Hubbard Hermetic CCUs
These instructions, recommendations are provided as a guide for the commissioning and maintenance of units
supplied by Hubbard Products Limited. These should be used in conjunction with your company’s health and safety
regulations, written work instructions and working practises to ensure that equipment is installed in a safe working
manner. Further requirements may be specified by the end user or local legislation. Risk assessments should be
carried out to ensure the safety of those conducting the work and anybody who may come into contact with the
equipment during any of these procedures. Please ensure you are equipped with the correct and appropriate PPE,
personnel protection equipment before commencing any work. Any work carried out should be completed by
competent qualified personnel.
Commissioning Index;
13.1 Leak testing by pressure testing
13.2 Vacuuming
13.3 Electrical testing
13.4 Charging Refrigerant
13.5 Commissioning
13.6 Operational Checkout
13.7 Lubricant Oil COndition
13.1 Leak testing by Pressure Testing
Before pressure test it is necessary to identify the refrigerant for operation, positions of all pressure relief valves
fitted and values, devices with restrictive pressure values ( e.g. LP switches) , and the system design maximum
operating pressures. The maximum operating pressures of the high and low side of the system will be stated on
the serial plate, note however that safety switches should be set 10% below these values to prevent pressure relief
valves discharging.
If you intend to pressure test with the pressure relief valves fitted the maximum values for test should be:
If high side pressure relief valves are fitted only:
High side: 80% of high PRV valve rating.
Low side: 80% of low PRV valve rating*
Before testing ensure with supplier that the equipment has been designed to operate at these conditions,
as pipe-work gauges may be incorrect. The Serial Plate will specify the maximum low side design pressure,
if low side is stated lower than high then a low side pressure relief valve must be fitted.
If high side and low side pressure relief valves are fitted:
High side: 80% of high PRV valve rating.
Low side: 80% of low PRV valve rating
If you intend to test to higher pressures or strength test the system please remove the pressure relief valves
before commencing to retain there integrity. The maximum operating pressures of the high and low side of the
system will be stated on the serial plate, note however that safety switches should be set 10% below these values
to prevent pressure relief valves discharging.
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Procedure:
Testing by visual examination, and a proprietary bubble solution. Ensure your supply cylinder of Oxygen Free
Nitrogen (OFN) is fitted with a pressure limiting device set at just above your maximum test pressure value. Never
move a cylinder with a regulator fitted.
At this stage the refrigeration compressors must remain electrically isolated from the system.
Open all liquid and suction valves and ensure that no system circuits are isolated by closed solenoid valves or non-
return valves etc. First introduce dry oxygen free nitrogen (OFN) at a pressure of 3 barg to the system and check
for audible leaks. If all components and pipe-work is sound, before proceeding to the second stage it is necessary
that the following components are isolated:
1. Compressors
2. Pressure Switches
3. Transducers
The test pressure should now be increased to 10 barg using dry oxygen free nitrogen in stages of no more than 3
bar at a time. Listen for audible leaks and watch the gauge for pressure loss at each increment. Use leak detection
soapy water at each joint to identify any small leaks. Leaks encountered should be repaired with the system de-
pressurised.
When the test pressure has reached 10 bar, thoroughly test all joints and components etc. for leaks. The pressure
should then be increased to no more than the maximum leak test pressure allowed for the particular section of the
system, isolating any PRV's or controls etc. which may be susceptible to the test pressure, and all components
should again be checked for leaks.
Strength Test
Follow the above procedure then prove the system. The system should be held at test pressure for at least 15
minutes. If the pressure has not significantly reduced then the system can be slowly vented to the leak test
pressure value. At which point the system should be checked again for leaks.
After all tests are completed the system should be de-pressurised gradually.
13.2 Electrical Testing
BEFORE commencing any testing procedure, a check must be made to ensure that NO electronic or extra low
voltage devices are connected. COMPLETE isolation of these items must be achieved prior to testing.
1. Test for earth continuity. This test is to verify that in no instance should the resistance between the earth
conductor (or control panel main earth terminals) and the metal parts exceed 0.1 ohm.
The electrician MUST ensure that the resistance in the earth conductor between the mains incoming supply and
our control panel earth terminal does NOT exceed the figure quoted above. It is also the responsibility of the
electrician to ensure that the earth conductor into our control panel is sized in accordance with the latest edition of
I.E.E. regulations.
A current of 25 amps should be passed between the control panel main earth terminal and all exposed metal parts
in turn. The test shall be made at a voltage not exceeding 6v ac.
Small isolated metal parts on, in or through non-conducting material, and separated by such material from current
carrying parts in such a way they cannot become live, should not be included in the test.
2. A test of polarity should be made and it should be verified that all fuses and single pole control devices are
connected in the phase conductor only.
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13.3 Evacuation
Before starting the vacuum procedure it is necessary to open by hand the high pressure valve (HPV), see section
11 above. Also you can refer to P&ID attached in this maunal. For this operation the magnetic tool shown below
needs to be used.
CAREL Product Reference & name: EEVMAG000 – Valve actuator
The operator can stop the vacuum procedure when the standing vacuum pressure (SVP) reaches 0.5 Torr.
13.4 Charging Refrigerant into the System
Initial charging should only be completed once the system has been proven to be leak free and after proper
vacuum. The charging point is located on the liquid line adjacent to the drier assembly. Liquid or gas should not be
added through the low pressure side of the system. Break vaccum with ONLY CO2 vapour (vapour off take
cylinder) up to 8 to 10 bar pressure. By using vapour CO2 up to that pressure you can avoid any dry-ice formation.
Make sure that compressor is off during this operation.
Maximum amount of refrigerant can be found below.
13.5 Commissioning
Commissioning Step One
1. Remove the main fuses or switch off the circuit breakers for the compressor.
2. Switch on the main isolator on the unit.
3. Switch on each system, individually; checking as the systems are brought on that fans, lights etc. are operating
properly. Check liquid solenoid valves operation and rotation of condenser fans (when fitted). When satisfied that
all systems are functioning, switch off main supply.
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4. Replace compressor fuses or switch on circuit breaker for the lead compressor only to ensure all systems are
refrigerating during commissioning.
5. If additional oil is needed, please add through the valve in 1st stage suction line. You can find more details in oil
charge section.
6. Switch on the main isolator. Providing enough refrigerant is in the system, the lead compressor will start up and
adding more refrigerant to the plant can commence.
Commissioning Step Two
Charging of the system should continue until the receiver is approximately 25% full, and the discharge pressure
approaching design value. When this condition has been reached, shut off all charging cylinders and allow the
compressor to run normally.
Check now that all the systems/stubs are refrigerating satisfactorily, evaporators fully frosted etc.
Commissioning Step Three
Now replace remaining compressor fuse circuit breakers and allow electronic compressor controller to stage in
compressors as required.
Commissioning Step Four
During the general commissioning the following electrical items should be checked:
1. Sub fuses, circuit breakers correct.
2. Main fuses, circuit breakers are correct and balanced.
3. Main compressor fuses and circuit breakers are correct.
4. All cable connections are tight.
5. Motor starter controls/contactor overloads are set correctly.
6. Check all contactors operate correctly.
13.6 Operational Checkout
When the system has been charged and has operated for at least 2 hours at normal operating conditions without
any indication of malfunction, it should be allowed to operate overnight on automatic controls. Then a thorough re-
check of the entire system operation should be made as follows:
1. Check the unit head and suction pressures. If the pressures are not within the system design limits, determine
why and take corrective action.
2. Check the liquid line sight-glass and expansion valves operation. If there are indications that more refrigerant is
required, leak test all connections and system components and repair any leaks before adding refrigerant.
3. Expansion valves must be checked for proper superheat settings.
Expansion valve probes must be in positive thermal contact with suction lines.
Valves with high superheat settings produce little refrigeration and poor oil return.
Too little superheat causes low refrigerant capacity and promotes liquid slugging and compressor oil removal.
LIQUID REFRIGERANT MUST BE PREVENTED FROM REACHING THE COMPRESSOR.
4. Using suitable instruments carefully check line voltage and amperages at the compressor terminals. Voltage
should be within 10% of the nameplate voltage.
The current should not exceed that on the nameplate rating. If amperage draw is excessive, immediately
determine the cause and take corrective action. On three phase motor-compressor, check to see that a balanced
load is drawn by each phase. Check all fan motors on air-cooled condensers and in fixture evaporator coils for
correct rotation. Fan motor mounts and fan blades should be carefully checked for tightness and proper alignment.
All motors requiring lubrication should be oiled or greased as per manufacturer’s recommendations. Check all
electrical load bearing terminals for tightness.
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5. When this stage is reached, the unit can now be left running on full automatic operation, commissioning sheets
checked and completed-Section 9. The plant should be allowed to run for a further few days and then a further
check made of all controls and any minor adjustments made.
6. The hints and procedures on commissioning are based on experience to date and checks made of units running
during both winter and summer periods. Do ensure that the settings of the components are correct before making
any adjustments.
7. DO NOT adjust components without satisfying yourself that there is good reason to do so. If adjustments are
carried out, record the final setting on the commissioning report.
13.6.1 Compressor bypass valve
Please refer to P&ID for compressor bypass valve position. The role of bypass valve is very critical for the rotary
compressor operation especially when the compressor is getting the signal to run. The valve is fully open when the
unit is switched off. This valve ensures the pressure balance between interstage and first-stage suction of the
compressor. That helps the compressor to start smothly.
14. Service and Maintenance
The following notes are not designed as a definitive guide, the maintenance procedures should be applied in
conjunction with your companies work instructions and working practises. Any further information not covered by
this section may be obtained from Hubbard Products Ltd on request.
14.1 Oil Management System
The suction line has to be properly sized to provide good oil return . Standard practice for oil traps must be
followed when condensing unit or evaporator are installed at diffeferent heights.
To assist with service/maintenance operations, shut-off valve is fitted to enable isolation.
The maximum high difference alloawance between condensing unit and evaporator should be no more than 10
meters. In case install outdoor unit under indoor unit, provide riser piping is close to indoor unit as shown below.
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In case install outdoor unit above indoor unit provide oil trap as shown below (1 oil trap at 5m is recommended).
14.2 Changing the Compressor Oil
Refrigeration oil is of bright, transparent appearance even after extended operation. However, various conditions
of the system can affect the oil such as insufficient evacuation of the system on start up, dirt from the pipework on
installation and excessive discharge temperatures. Initial Oil type is stated on the serial plate, for alternatives refer
to Hubbard Technical.
When the oil is seen to be in an unclean condition it should be changed to avoid consequential compressor
damage.
14.4 Changing a Compressor.
These instructions may be supplemented by additional reference material provided.
ATTENTION
Please ensure all work carried out is in accordance with your companies working
practices and that the required equipment/PPE is available and used.
WARNING
Pipework associated with the condenser will be at extreme temperatures.
WARNING
Ensure condenser electrical supply is fully isolated and locked off prior to working on
unit.
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