SCM Cuno 2 Aqua User manual

FR
DE
EN
1
OEM Manual (EN)
Version UMT/WG T-BT OEM rev. 3.0 date 08/10/2021
OEM-Handbuch (DE)
Version UMT/WG T-BT OEM Rev. 3.0 Datum 08/10/2021
Manuel OEM (FR)
Version UMT/WG T-BT OEM rév. 3.0 date 08/10/2021
Manufactured by SCM REF AB - Sweden

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 1-EN
OEM Manual (EN)
Version UMT/WG T-BT OEM rev. 3.0 date 08/10/2021
Manufactured by SCM REF AB - Sweden

EN
OEM Manual –CUBO2AQUA
Pag. 2-EN UMT/WG T BT Rev3.0 –08/10/2021
Manual Guide
POINT 1-2 > INTRODUCTION & SAFETY
POINT 3-6 > UNIT DESCRIPTION
POINT 7 > COMMISSIONING
POINT 8 > SOFTWARE –USER INTERFACE
POINT 9 > SERIAL COMMUNICATIONS
POINT 10 > MAINTENANCE
POINT 11-13> ALARMS AND TROUBLES
POINT 14-21> TECHNICAL DATA

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 3-EN
Contents
1 Introduction .......................................................................................................................................................................4
2 Safety issues with CO2- Safe handling ...........................................................................................................................4
2.1 Precaution.................................................................................................................................................................4
3 Unit description & Main components.............................................................................................................................6
4 Unit installation .................................................................................................................................................................7
5 Piping details .....................................................................................................................................................................8
5.1 Pipe Connections (Multi-Split) ................................................................................................................................8
5.2 Oil traps.....................................................................................................................................................................8
6 Test and inspection before start-up ...............................................................................................................................9
6.1 Control of the unit tightness...................................................................................................................................9
6.2 Preliminary controls according to EN 60204-1, visual controls..........................................................................9
6.3 Management of the system. Configuration of the controllers...........................................................................9
6.4 Inspection of the water loop................................................................................................................................ 10
6.5 Earth connection................................................................................................................................................... 10
7 Commissioning............................................................................................................................................................... 11
7.1 Evacuation and pre-charge.................................................................................................................................. 11
7.1.1 “VACUUM”, SW function details...................................................................................................................11
7.2 Refrigerant & Oil Charging ................................................................................................................................... 12
7.2.1 Oil charge.......................................................................................................................................................12
7.2.2 Procedure for additional oil refill................................................................................................................12
7.2.3 Estimation of the refrigerant charge ..........................................................................................................13
7.2.4 Charging procedure......................................................................................................................................15
8 User Interface and main Software features................................................................................................................ 16
8.1 User Interface........................................................................................................................................................ 16
8.2 On/Off unit............................................................................................................................................................. 18
8.3 Regulation set point.............................................................................................................................................. 19
8.4 MPXPRO and ULTRACELLA/EVO CAREL configuration. .................................................................................... 20
8.5 MPXPRO and ULTRACELLA/EVO CAREL regulation ........................................................................................... 21
9 Serial Communication (PSD drivers, Evaporators and Supervisory System) .......................................................... 22
9.1 Communication with evaporators (features and requirements) .................................................................... 22
9.2 Serial connections and wirings............................................................................................................................ 23
10 Recommended Annual Checks..................................................................................................................................... 24
11 List of alarms .................................................................................................................................................................. 27
11.1 Hecu alarm............................................................................................................................................................. 27
11.2 PSD (Power+) alarm code..................................................................................................................................... 33
11.3 PSD led status........................................................................................................................................................ 35
12 Troubleshooting ............................................................................................................................................................. 36
13 Compressor Envelope ................................................................................................................................................... 37
14 Refrigerant drawing (P&I).............................................................................................................................................. 38
15 HECU Controller layout ................................................................................................................................................. 39
16 Terminals blocks connection ........................................................................................................................................ 40
17 Dimensional drawing..................................................................................................................................................... 40
18 General information and limits .................................................................................................................................... 41
19 Electrical details.............................................................................................................................................................. 41
20 Cooling capacity Table ................................................................................................................................................... 43

EN
OEM Manual –CUBO2AQUA
Pag. 4-EN UMT/WG T BT Rev3.0 –08/10/2021
1Introduction
CUBO2AQUA is an high efficiency condensing unit (for CO2 transcritical application) equipped with BLDC
variable speed compressor. It is compact, easy to install and can directly communicate with the
refrigerated units.
Thanks to these features it is a very efficient (even at partial load) without any compromise with the food
conservation.
This manual refers to CUBO2AQUA models designed for cooling and conservation at low temperatures.
They are identified as:
UMT/WG T 030 BT DX
UMT/WG T 045 BT DX
UMT/WG T 067 BT DX
UMT/WG T 100 BT DX
2Safety issues with CO2- Safe handling
When the R744 (CO2) is being handled, a qualified person must be present with the suitable equipment.
CO2 has no smell or colour and the operator would not be aware if there were any leaks.
The effects of increased CO2 levels on adults at good health can be summarized:
2.1 Precaution
Dedicated pressure relief valves are necessary in all those sections of the system which can be
isolated by shut valves. Due to the high thermal coefficient of expansion of liquid CO2, fluid
pipes must not be blocked.
All SCM units are protected against overpressure with pressure relief valves when required
according to EN378 and PED.
Given the high pressure that system can reach during operation, special attention must be paid
to connect and regulate the unit.
Before carrying out any repairs which involve breaking into the system/soldering or welding,
all relevant parts must be emptied of CO2.
Do not use other than the designated refrigerant (for charging, adding or recharging)
Refrigerant gas leak may cause suffocation.
Piping, equipment components and tools should be appropriate for use with R744 (CO2
refrigerant).
CO2 concentration
Effects
%
ppm
0,04 %
< 400
Normal outdoor level
0,06 %
< 600
Acceptable levels
0,50 %
5000
8hours - Long Term Exposure Limit
1,5 %
15.000
15 minute - Short Term Exposure Limit.
3 %
30.000
Intoxicating, breathing and pulse rate increase, nausea.
10 %
100.000
Inconscious, further exposure death.
30 %
300.000
Quick death.

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 5-EN
Use of unsuitable components or those designed for HFC refrigerant may cause serious
incidents such as equipment failure and rupture of the refrigerant cycle.
Securely place the cover on the electrical box and enclosure panel. Incomplete attachment may
lead to penetration of water and living creatures, meaning potential current leak and
fire/electrical shock.
Do not change the set values of the safety device.
Using the refrigeration unit with changed values may cause failure of the safety stop function
and lead to a burst or fire.
When abnormal operation is detected, or before starting disassembly or repair, turn off the
main power switch.
Specified components must be used for repair.
Use of non-specified components may cause failure of the safety stop function and lead to
burst or fire.
Incorrect moving may cause falling or dropping of the refrigeration unit, and cause injury.
Request a specialty operator for disposing the refrigeration unit.
Make sure that access and emergency exit ways are not obstructed to comply with the local
regulations.

EN
OEM Manual –CUBO2AQUA
Pag. 6-EN UMT/WG T BT Rev3.0 –08/10/2021
3Unit description & Main components
Low temperature condensing unit is equipped with 2 BLDC compressors having the same size.
They work as in a booster system. One compressor is taking in charge the evaporation pressure control
for the low temperature refrigerated devices. The other one (PARALLEL) is controlling the pressure in the
receiver. No flash valve is installed in this unit.
The system operates at the following pressures:
Parallel Compressor discharge pressure (PGC) : operating between 45-105 bar.
Parallel Compressor suction pressure/Receiver pressure PREC : operating between 32-60 bar.
LT suction pressure : operating between 12-18 bar.
Compressor modulation range: 25 –100 rps
LT
compressor
Speed driver
LT compressor
PARALLEL
compressor
Speed driver
PARALLEL
compressor
PHE Gas
Cooler
HPV
valve
Receiver
3 Way
Valve
Liquid filter
dryer
NRV
Valve
Electrical
board
Water
Inlet
Water
Outlet

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 7-EN
4Unit installation
The unit has been designed for outdoor installation.
Respect distances for correct operation/ maintenance.
In the case of several units in series or in parallel mode, respect the minimum distances for
properly maintenance.
Minimum maintenance distances.
Vertical installation
Horizontal installation

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OEM Manual –CUBO2AQUA
Pag. 8-EN UMT/WG T BT Rev3.0 –08/10/2021
5Piping details
5.1 Pipe Connections (Multi-Split)
The connection between the Condensing Unit and more remote evaporators can be the same one used
for Multi-Split or branch system.
The preferred one is the one is able to guarantee the highest gas velocity in the suction line (for a good
oil return) with a low pressure drop.
For Multi-Split layout, the system requires a dedicated suction line for each evaporator that will
be collected by a manifold installed close to the condensing unit. Please refer to the example
reported in the below pictures.
Multi-Split Branch
For Multi-Split system the collector must be properly sized and installed in a horizontal
position
SCM Frigo recommends connection with up to 3 remote evaporators, and maximum
suction pipe length of 20 meters to each evaporator.
Liquid line must be properly sized to supply the farther evaporators (liquid velocity < 1 m/s is
suggested).
Suction line must be properly sized to have a good oil return with a low pressure drop (gas velocity
from 3 to 8 m/s are suggested).
The condensing unit connection sizes are not necessarily the correct size for the installed pipe
network and should be sized for each installation to ensure acceptable penalties and velocities.
5.2 Oil traps
If UMTT and evaporator are installed at different heights, it is necessary to create piping oil traps.
The installation of an oil-trap is recommended (one oil-trap every 2/3 meters of difference in
height)

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 9-EN
6Test and inspection before start-up
6.1 Control of the unit tightness
All units are pressure tested and checked for leaks.
Each unit is delivered with a nitrogen charge pressure of 2 bar.
It is recommended before proceeding with the installation, to check the pressure of the refrigeration
system of the unit using a suitable manifold gauge in order to detect possible leaks.
6.2 Preliminary controls according to EN 60204-1, visual controls
1. General PE terminal present and identified.
2. All other terminals clearly identified, with the ground symbol or two-colour yellow-green lead.
3. Terminals for exclusive connection to the equipotential connections.
4. Only one lead connected to each terminal.
5. Yellow/green insulation on the ground lead.
6. No live leads with yellow or green insulation.
7. No pipes or raceways used as lead protections.
8. No fuses, switches or circuit breakers on the equipotential protection circuit.
9. Lead sizes conform to the minimum sizes given by current standards.
10. Check the electric connections have been made correctly. Especially the phase connections:
open the box with the compressor terminal block, the connections must conform to the diagram
given in the compressor electric box.
6.3 Management of the system. Configuration of the controllers
The unit is equipped with the controller Carel prackCO2 Hecu, which is managing the working
parameters as following
BT compressor is managed according to suction pressure
3way valve to modulate the water flow in the PHE Gas cooler is managed to keep the gas cooler
outlet temperature few degrees above the water inlet temperature
Gas cooler pressure is managed according to the gas cooler outlet temperature in order to
achieve the best COP
Receiver pressure is regulated with a floating set-point within a user defined range (32-38 bar)
All alarms related to compressor and pressure levels are monitored
Refer to electrical diagram and controller configuration list, attached to this manual, to check
the configuration.

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OEM Manual –CUBO2AQUA
Pag. 10-EN UMT/WG T BT Rev3.0 –08/10/2021
6.4 Inspection of the water loop
The cooling of the discharge gas coming from the compressor is occurring inside the PHE Gas Cooler.
The PHE installed in the CUBO2 AQUA is a Gas-Water heat exchanger and the water flow is controlled
by a 3Way Modulating Valve according to the Gas Cooler outlet temperature.
Before switching on the condensing unit, it is important to be sure that the water loop side is
operating properly (both the circulation and water temperature).
Suggested Water Inlet temperature (in the GC PHE) range is +7°C - +37°C.
6.5 Earth connection
The unit must be connected to the ground line, using the terminal provided by the constructor
before the unit is turned on for the first time after installation. The customer is responsible for the
connection and the efficient grounding in conformity with current legislation in force and for
periodically checking the state of the same.
Main switch
Prack HECU Display
Protection
s
Prack HECU
Controller

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 11-EN
7Commissioning
The unit leaves the factory without being filled with refrigerant.
The compressor and receiver are pre-charged with oil.
The customer is responsible for charging the system with CO2 and adding more oil (only if strictly
necessary).
The instruction given herein are a reminder of the best method to protect the unit, which could be seriously
damaged in the event it is not filled correctly.
7.1 Evacuation and pre-charge
EEVMAG0000
Before starting the vacuum procedure, it is necessary to open the high
pressure valve (HPV) and the compressor equalization valves.
To open the valves a software based function (VACUUM) is available
in the Cubo2 AQUA SW (find below some details).
As an alternative you can open the valves manually. HPV valve can be
opened with the Carel magnetic tools supplied with unit. (See photo on
side). The magnet opening & closing direction is marked on the top –
Clockwise to Open.
Evacuate the system from both the high and low side condensing unit
service connections.
Stop the Vacuum procedure only when the “standing vacuum pressure”
reach a value of 0.67mbar. During the vacuum process brake the vacuum
several time with dry nitrogen.
Before starting refrigerant charge, break vacuum WITH ONLY CO2
VAPOUR (all parts of circuit) up to 10bar pressure to avoid dry-ice
production.
Do not switch on the compressor during this phase!
7.1.1 “VACUUM”, SW function details
This function can be activated only while the unit is in OFF (regulation OFF) and the target is to
automatically open HPV and Compressors equalization solenoid valves.
1
Main menu –Inputs & outputs
2
Manual Management
3
Vacuum
4
5
6

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OEM Manual –CUBO2AQUA
Pag. 12-EN UMT/WG T BT Rev3.0 –08/10/2021
Select “YES” – This will then open HPV
and equalizaztion valve according to the
settings in mask Bbd02
Set the wanted valves status during the
Vacuum
O = Open / C = Close
The status on the front screen will now
indicate “Unit OFF by vacuum”, in this
state the CDU cannot be set in ON.
The above step should be reversed prior
to charging the unit
7.2 Refrigerant & Oil Charging
7.2.1 Oil charge
All CUBO2AQUA are equipped by SCM with an additional pre-charged of
250ml of Oil (type PAG VG100) in the receiver. This info is highlighted with
a label applied in the switch panel door.
Take care to avoid moisture ingress. PAG oil is extremely hygrosopic!
Oil type approved is DAPHNE PZ100S or RENISO PAG100.
7.2.2 Procedure for additional oil refill
1. Close the evaporator electronic expansion valve by
raising the set point of the cooled space.
2. Wait for the CUBO to pump down and switch off the
compressors
3. Switch off the condensing unit (using ON/OFF
command on the display)
4. Close ball valve 3 in the CDU (90 on circuit diagram)
5. Fully open the evaporator electronic expansion valve
using the Carel magnet or using suitable manual
process for your EEV
6. Vent gas at valve 1 until pressure drops to 0 bar g
(check on display)
Internal check valve (138 on circuit diagram) will
prevent emptying the whole circuit
7. Connect a line from the oil can to valve 2 (liquid line
service port) and using a vacuum being drawn from
valve 1 (via the evaporator), pull the oil into the liquid
line.
8. When all the oil is in the system shut valve 2 (liquid
line service port) and continue to pull the system into
deep vacuum from valve 1 only.
9. When the vacuum is achieved charge vapour through
valve 1 up to 10 bar
10. Restore the automatic management of evaporator
electronic expansion valve and reset the set point if
adjusted.

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 13-EN
11. Open ball valve 3 in the CDU (90 on circuit diagram)
12. Switch ON the unit (using ON/OFF command)
13. Recharge some additional refrigerant (same quantity
removed from liquid line)
7.2.3 Estimation of the refrigerant charge
To calculate the refrigerant quantity to charge in the system you should know:
Volume of evaporator coil
Diameter and Length of the piping
Liquid Receiver volume and Gas Cooler volume
The total charge of refrigerant will be the obtained summing up the single quantity needed for the
evaporators, for fill the liquid line and considering the quantity will stay in the Gas Cooler and in the liquid
receiver (refer to the below example).
We recommend to use the Excel calculation sheet to calculate the quantity of refrigerant to charge in
the system. You can get it from SCMFrigo.
Regardless from the calculation results, the minimum recommended CO2 charged is 4kg.
For estimation greater than 4kg the quantity of charged CO2 must be the calculated one.
The max permitted CO2 charge must guaranty that, in case of pump down at EEV in front of
Evaporators, refrigerant inside the receiver will not exceed 7.2kg. This is not the total system charge, it is
the refrigerant that will be in the receiver when the system pumps down from the evaporator expansion device!
Data for calculation:
Receiver 8L min quantity of CO2 = 2,4 kg
PHE Gas Cooler quantity of CO2 = 0,21 kg

EN
OEM Manual –CUBO2AQUA
Pag. 14-EN UMT/WG T BT Rev3.0 –08/10/2021
Using this diagram you can calculate refrigerant
charge related to the evaporator inner volume.
Using this diagram you can calculate refrigerant
charge related to the pipe diameter and length. You
can refer even to the following table.
Pipe length (m)
Liquid
line
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
K65 -
120bar
3/8’’(gr)
230
270
320
360
410
460
500
550
590
640
680
730
770
820
860
910
K65 –
120bar
1/2’
(gr)
410
490
570
650
730
810
900
980
1060
1140
1220
1300
1380
1470
1550
1630
K65 –
80 bar
1/2’
(gr)
450
530
620
710
800
890
980
1070
1160
1250
1340
1420
1510
1600
1690
1780
Examples of refrigerant charge calculation
Example 1
Receiver
Standing charge
2.4 kg
PHE Gas cooler
Standing charge
0.21 kg
Evaporator Volume 2 dm3
Calculated from first graph
0.9 kg
Pipe length 8m x K65 3/8”
Calculated from second graph
0.4 kg
Pump down (from
evaporator)
Receiver / Evap ≤7.2 kg
3.3 kg
0,0
1,0
2,0
3,0
4,0
5,0
6,0
2 4 6 8 10 12
Refrigerant charge (kg)
Evaporator Volume (dm3)

EN
OEM Manual –CUBO2AQUA
UMT/WG T BT Rev3.0 –08/10/2021 Pag. 15-EN
Total System Charge
Receiver / Gas Cooler / Liquid line/ Evap
≤7.2kg
3.9 kg
Is charge >4kg (min charge)?
Charge < 4 kg
3.9 kg
Total refrigerant to charge is 4kg.
Example 2
Receiver
Standing charge
2.4 kg
PHE Gas cooler
Standing charge
0.21 kg
Evaporator Volume 12 dm3
Calculated from first graph
5.2 kg
Pipe length 8m x K65 3/8”
Calculated from second graph
0.4 kg
Pump down (from
evaporator)
Receiver / Evap ≤7.2 kg
7.6 kg
Total System Charge
Receiver / Gas Cooler / Liquid line/ Evap
≤7.2kg
8.21 kg
Is charge >4kg (min charge)?
Charge >4 kg
8.2 kg
Configuration not permitted. In pump-down condition the refrigerant inside the receiver
exceed the max quantity (7,2kg)
Don’t overfeed the unit with excessive charge to avoid compressor damaged.
7.2.4 Charging procedure
For charging, use port 1/4SAE (7/16”-
20UNF) on service valve
(PS120bar - CASTEL 6110E/X15)
Important remarks about the CO2 charging procedure:
CO2 of purity class of N4.0 or comparable or with moisture content <10 ppm must be used.

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OEM Manual –CUBO2AQUA
Pag. 16-EN UMT/WG T BT Rev3.0 –08/10/2021
Charge R744 vapour into the system to a pressure of 10 bar g then liquid charge into the liquid line
service port until you have charged the amount specified by the charge estimator.
Charge CO2 liquid only from liquid line.
Charge CO2 gas only from suction line.
Never charge CO2 liquid from suction to prevent the breakdown of the compressor.
Do not overcharge the system. A liquid overfeed can compromise correct regulation of the unit and
the reliability of the compressor (liquid return).
Liquid in the receiver must not never exceed 3,5 kg in the units with 2x2,4 lt and 7,2 kg in the
units with 1x8 lt (especially in transcritical and defrosting mode).
Do not mix CO2 with various other refrigerants.
8User Interface and main Software features
8.1 User Interface
Manufacturer PW: 1234
Button meaning
Display meaning
1
Shows active alarms list and accesses to
the alarm log.
If pressed for more than 5 sec., resets all
acknowledged alarms.
A
Active alarm preset and manual
operation.
2
Used to enter main mask tree.
B
Unit status.
3
Return to back mask or higer level.
C
Rotation speed of compressor
(rps)

EN
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4
Scroll a list upwards or increases the value
highlighted by the cursor.
D
Current Time and date.
5
Scroll a list downwards or decreases the
value highlighted by the cursor.
E
Operation Suction pressure (bar).
6
Enters in the selected submenu or confirms
the changed set values.
F
Outlet Gas Cooler pressure (bar).
Led color and meaning
Red / blinking
Active alarm and not acknoledged
Steady : alarms acknowledged
Yellow / Fixed
Controller actived
Green / Fixed
Controller powered

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OEM Manual –CUBO2AQUA
Pag. 18-EN UMT/WG T BT Rev3.0 –08/10/2021
8.2 On/Off unit
Even if the unit is powered, it will stay in stand-by (regulation OFF) until the user turns-on the
regulation (regulation ON).
The main steps to switch ON the regulation are reported here below:
From main menu, press “Enter” button and appear access with password (see A mask).
Note.
Current mask / total masks. The horizontal rows mean access level
Letters and numbers are the name of mask.
Set password (default: 1234) and press “Enter”.
Select “Unit Status” and press “Enter”.
Select “On/off” and press “Enter”
.
Press “Enter”, to change from off to ON
Press “Enter”, to change from on to OFF.