Marstair CX Series User manual

55908014-19
CX(E) SPLIT SYSTEMS
TECHNICAL MANUAL
CX(E) LOW TEPERATURE SPLIT SYSTEMS

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INDEX
CONTENTS
PAGE
PART NUMBERS, UNIT COMBINATIONS, OPTIONS
3
DIMENSIONS & WEIGHTS, PERFORMANCE DATA
4
AIR FLOW, SOUND POWER AND SOUND PRESSURE LEVELS
5
ELECTRICAL DATA
6
CX(E) DIMENSIONS
7
INSTALLATION
8
CKC PIPEWORK
8
CKC REFRIGERANT
10
ELECTRICAL: CONNECTIONS & FUSES
12
CX MATCHES
12
WIRING DIAGRAMS
13
CX(E) CONTROLS
15
CKC INSTALLATION: DIMENSIONS
16
COMPONENT IDENTIFICATION
CX(E) UNITS
17
CKC UNITS
18
1. TEV Ltd recommend that personnel working on this equipment be skilled and fully conversant with
the appropriate Air Conditioning, Refrigeration and Electrical practices and have sound knowledge
of current Industrial Safe Working practices.
2. CX(E) models are electromechanical / Electronic control units that use R407C refrigerant; they
provide cooling within the range of 2.8 –6.8 kW. These units are matched with CKC outdoor units
to complete a system.
CX(E) units are fitted with an expansion assembly, allowing the use of a liquid line. This can be
transferred to the outdoor unit (CKC only), when an expansion line is required to accommodate
longer pipe runs.
3. These units contain live electrical components, moving parts and refrigerant under pressure.
Always site out of reach of children and protect from vandalism.
4. The data plate only gives information for the CX(E) unit. For system details add input power and
current of indoor and outdoor unit, including any heater load.
GENERAL

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MODEL
CX 30
CX 40
CX 50
CX 70
PART NUMBER
55917001
55917002
55917003
55917004
MODEL
CXE 30
CXE 40
CXE 50
CXE 70
PART NUMBER
55917017
55917016
55917015
55917014
MODEL
CKC 20 1ph
CKC 30 1ph
CKC 50 1ph
CKC 80 1ph
CKC 80 3ph
PART NUMBER
55020720
55020730
55020722
55020723
55020724
EXPANSION DEVICE
55023323
55023324
55023327
55023329
55023329
Low Temperature Match
MODEL
CXE 40
CXE 50
CXE 70
PART NUMBER
55917016
55917015
55917014
MODEL
CKC 20 1ph
CKC 40 1ph
CKC 60 1ph
PART NUMBER
55020720
55020741
55020740
EXPANSION DEVICE
55023323
55023325
55023328
INDOOR UNIT
OUTDOOR UNIT
CX(E) 30
CKC 20
CX(E) 40
CKC 30
CX(E) 50
CKC 50
CX(E) 70
CKC 80
Low Temperature Match
INDOOR UNIT
OUTDOOR UNIT
CXE 40
CKC 20
CXE 50
CKC 40
CXE 70
CKC 60
OPTIONAL KITS
PART NUMBER
DESCRIPTION
55900700
3kW heater (CX only)
55900701
Digital temperature display (CX only) std on CXE
55900702
De-ice thermostat (CX only)
55900709*
Extended pipe run CX 30/40/50 only
55900710*
Extended pipe run CX 70 only
55900715
3kW heater (CXE only)
* When matched with CKC outdoor units
CX(E) OPTIONS
DIMENSIONS & WEIGHTS
UNIT COMBINATIONS
PART NUMBERS

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MODEL
UNPACKED
PACKED
CX(E)
HEIGHT
WIDTH
DEPTH
WEIGHT
HEIGHT
WIDTH
DEPTH
WEIGHT
30
483
845
320
18
530
950
370
21
40
483
845
320
18
530
950
370
21
50
483
845
320
20
530
950
370
23
70
483
845
320
23
530
950
370
26
CKC
HEIGHT
WIDTH
DEPTH
WEIGHT
HEIGHT
WIDTH
DEPTH
WEIGHT
1Ph
3Ph
1Ph
3Ph
20
620
900
310
46
-
625
980
340
48
-
30
620
900
310
48
-
625
980
340
55
-
50
720
1000
310
64
-
730
1080
340
66
-
60
720
1000
310
64
730
1080
340
66
-
80
720
1000
310
66
64
730
1080
340
68
66
MODEL
RATING CONDITIONS
(ROOM 12.7C / 10C) (AMBIENT 27C / 19C)
OPTIONAL ELECTRIC
HEATER
TOTAL
SHR
SENSIBLE
240V
230V
CX(E) 30 + CKC 20
2.80
0.75
2.10
3.25
3.0
CX(E) 40 + CKC 30
3.30
0.68
2.24
3.25
3.0
CX(E) 50 + CKC 50
4.60
0.66
3.02
3.25
3.0
CX(E) 70 + CKC 80
6.80
0.63
4.30
3.25
3.0
MODEL
RATING CONDITIONS
(ROOM 12.7C / 10C) (AMBIENT 35C / 19C)
OPTIONAL ELECTRIC
HEATER
TOTAL
SHR
SENSIBLE
240V
230V
CX(E) 30 + CKC 20
2.38
0.75
1.79
3.25
3.0
CX(E) 40 + CKC 30
2.81
0.68
1.90
3.25
3.0
CX(E) 50 + CKC 50
3.91
0.66
2.57
3.25
3.0
CX(E) 70 + CKC 80
5.78
0.63
3.66
3.25
3.0
Low Temperature Match
MODEL
RATING CONDITIONS
(ROOM 5Cdb/ 3Cwb) (AMBIENT 27C / 19C)
OPTIONAL ELECTRIC
HEATER
TOTAL
SHR
SENSIBLE
240V
230V
CXE 40 + CKC 20
2.3
0.85
2.0
3.3
3.0
CXE 50 + CKC 40
3.5
0.80
2.8
3.3
3.0
CXE 70 + CKC 60
5.0
0.70
3.5
3.3
3.0
MODEL
RATING CONDITIONS
(ROOM 5Cdb/ 3Cwb) (AMBIENT 35C / 19C)
OPTIONAL ELECTRIC
HEATER
TOTAL
SHR
SENSIBLE
240V
230V
CXE 40 + CKC 20
2.0
0.85
1.7
3.3
3.0
CXE 50 + CKC 40
3.0
0.80
2.4
3.3
3.0
CXE 70 + CKC 60
4.3
0.70
3.0
3.3
3.0
PERFORMANCE DATA (kW)

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AIR FLOWS
MODEL
m³/s
MODEL
m³/s
CX(E) 30
0.61
CKC 20
0.97
CX(E) 40
0.61
CKC 30
0.97
CX(E) 50
0.66
CKC 50
0.97
CX(E) 70
0.58
CKC 80
0.97
INDOOR UNIT
MAXIMUM
SPEED
SOUND POWER LEVELS
SOUND PRESSURE
LEVELS
SPEED
Frequency Hz
125
250
500
1K
2K
4K
dB(A)
CX(E) 30
69.1
67.7
67.6
65.6
62.2
56.0
39
CX(E) 40
69.1
67.7
67.6
65.6
62.2
56.0
39
CX(E) 50
71.7
69.2
69.1
67.1
63.2
58.5
40.5
CX(E) 70
70.1
68.2
68.6
66.1
63.2
57.5
39.9
Sound Pressure Levels in dB(A) at 10m distance in free field conditions. (Reference 2x10 ⁻⁵ N/m²)
OUTDOOR UNIT
MAXIMUM
SPEED
SOUND POWER LEVELS
SOUND PRESSURE
LEVELS
SPEED
Frequency Hz
125
250
500
1K
2K
4K
dB(A)
CKC 20
77
67
69
65
60
54
39.2
CKC 30
77
68
69
65
60
54
39.3
CKC 50
74
68
67
66
61
54
38.9
CKC 60
73
68
68
66
62
54
39.3
CKC 80
71
69
68
65
60
54
38.7
Sound Pressure Levels (SPL) at 10m distance in free field conditions. (Reference 2x10 ⁻⁵ N/m²)
SOUND POWER AND SOUND PRESSURE LEVELS

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MODEL
INDOOR/OUTDOOR
1 PH 230V 50Hz
INPUT POWER
FULL LOADS AMPS
SYSTEM
MAX.
STARTING
CURRENT
COOLING
HEATING
COOLING
HEATING
kW
kW
AMPS
AMPS
AMPS
CX(E) 30 + CKC 20
1.3
2.9
7.7
13.8
30
CX(E) 40 + CKC 30
1.6
2.9
8.2
13.8
38
CX(E) 50 + CKC 50
2.2
2.9
9.7
13.8
60
CX(E) 70 + CKC 80
3.2
2.9
12.3
13.8
78
MODEL
INDOOR/OUTDOOR
3 PH 400V 50Hz
INPUT POWER
FULL LOADS AMPS
SYSTEM
MAX.
STARTING
CURRENT
COOLING
HEATING
COOLING
HEATING
kW
kW
AMPS
AMPS
AMPS
CX(E) 70 + CKC 80
3.2
2.9
5.7
13.8
42
Low Temperature Match
MODEL
INDOOR/OUTDOOR
1 PH 230V 50Hz
INPUT POWER
FULL LOADS AMPS
SYSTEM
MAX.
STARTING
CURRENT
COOLING
HEATING
COOLING
HEATING
kW
kW
AMPS
AMPS
AMPS
CXE 40 + CKC 20
1.3
3.1
7.15
12.8
28
CXE 50 + CKC 40
2.1
3.1
10.2
13.8
50
CXE 70 + CKC 60
2.4
3.1
9.8
13.8
61
UNIT ELECTRICAL LOADS [230V 50Hz 1Ph (A) or 400V 50Hz 3Ph (A/Ph)]
MODEL
FAN MOTOR
HEATER
CX(E) 30
0.8
13.0
CX(E) 40
0.8
13.0
CX(E) 50
0.8
13.0
CX(E) 70
0.8
13.0
CKC
20
30
40
50
60
80
Fan motor
0.6
0.6
0.6
0.6
0.6
0.6
R407C compressor (1 Ph) nominal FLA
6.0
10.4
10.2
8.3
9.8
10.9
R407C compressor (3 Ph) nominal FLA
-
-
-
-
-
4.3
Crankcase heater
0.25
0.25
0.25
-
0.25
-
ELECTRICAL DATA

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CX(E) DIMENSIONS
DIMENSIONS (mm)
CONDENSATE DRAIN 22mm OD
96
35 65 TYP.
140
75
215 36
17.5
17.5
39
39
124
422.5
70
845
888
124
888 (Fixing centres)
(Fixing centres)
320
96
MIN. 500
FOR SIDE ACCESS
483
20
X = Interconnecting Wiring
Z1= Suction
Z2= Liquid / Expansion
SIDE VIEW
(Wall mounted)
X
Z1
Z2
X
SIDE VIEW
(Ceiling mounted)
TOP VIEW
(Ceiling Mounted)
REAR VIEW
(Wall mounted)
FRONT VIEW
(Wall mounted)
120
MIN. 120
MIN.

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INSTALLATION
CONTENTS
PARTS DESCRIPTION
QTY
ACTION
Envelope containing operating instructions and
Declaration of Conformity
1
Pass to the end user.
Mounting brackets
2
Use to hang unit.
Drain Stub/Nut/Gasket
1
Fitted by installer.
Drain stub adaptor
1
Convert to ¾" drain if required.
Screw M5
6
To fix brackets to unit.
Washer nylon
6
To fix brackets to unit.
Washer M5 shakeproof
6
To fix brackets to unit.
Reducing flare nut 1/2” – 3/8”
1
Fit to liquid connection on the CXE 70 indoor unit
when matched with a CKC 60 outdoor unit
The unit may be mounted on a wall or solid ceiling using brackets supplied. It should be matched with the appropriately
sized outdoor unit; this instruction should be used in conjunction with the outdoor unit installation instructions.
UNIT COMBINATIONS
1. Fit all kits prior to installing the unit. (Heater kit is easier to fit when unit has been mounted).
2. Ensure that the mounting surface will support the operating weight of the unit (see table below).
3. Mark out the mounting positions and drill holes to suit 6mm rawlbolt shields or equivalent strength fasteners
(ensure that the unit is positioned to give sufficient access (min 0.5m) to the removable side panel).
4. Fix the mounting brackets to the unit in the correct position for wall or ceiling mounting.
5. Raise the unit into position and secure the fixings,
ensuring that it is square and level.
6. Remove the drain tray then fit the drain stub, nut &
gasket. Refit the drain tray.
NITROGEN CHARGE
The unit contains a small charge of dry nitrogen, which should
be discharged into the atmosphere. This is a non-toxic, non-
ozone depleting gas with no global warming potential.
FITTING LOSSES, in equivalent straight lengths of pipe (m).
FITTING
Pipe Size OD
To calculate the total equivalent
length, the equivalent lengths of all
fittings in a pipe run must be added
to the actual length of pipe in the
run: these are the fittings most
likely to be used.
R = Radius of bend
d = Diameter of tube
C = Centres of bend
3/8"
1/2"
5/8"
3/4"
7/8"
45° Bend
0.12
0.15
0.18
0.21
0.24
90° Bend R/d = 1
0.37
0.43
0.49
0.55
0.61
90° Bend R/d = 1.5
0.24
0.27
0.3
0.37
0.43
180° Bend R/d = 1.5
0.73
0.91
1.1
1.28
1.46
180° Bend C/d = 2.5
0.46
0.55
0.64
0.76
0.85
90° Elbow
0.67
0.85
1.04
1.25
1.46
A. USING SUCTION AND LIQUID LINES:
With the expansion device connected to the indoor unit, the equivalent pipe run should be 20m maximum,
including a maximum lift of 7.5m. Fully insulate the suction line. Ensure the suction pipe is insulated well over
the drain tray at the indoor unit. Liquid lines should be routed to avoid hot areas. This prevents flash gas
forming, which may result in erratic control of liquid refrigerant to the evaporator.
MAXIMUM EQUIVALENT LENGTH OF SUCTION LINE PIPE SIZES (m)
LIQUID LINE
SYSTEM
3/8"
1/2"
5/8"
3/4"
1/4"
3/8"
CX(E)30 + CKC20
7.5
20
-
-
20
-
CX(E)40 + CKC30
-
15
20
-
-
20
CX(E)50 + CKC50
-
7.5
18
-
-
20
CX(E)70 + CKC80
-
-
11
20
-
20
MAXIMUM EQUIVALENT LENGTH OF SUCTION LINE PIPE SIZES (m)
LIQUID LINE
Minimum Set Temperature 4°C
INDOOR UNIT
OUTDOOR UNIT
CXE 40
CKC 20
CXE 50
CKC 40
CXE 70
CKC 60
Minimum Set Temperature 8°C
INDOOR UNIT
OUTDOOR UNIT
CXE 30
CKC 20
CXE 40
CKC 30
CXE 50
CKC 50
CXE 70
CKC 80
DRAIN TRAY
GASKET
NUT
DRAIN STUB

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SYSTEM
3/8"
1/2"
5/8"
-
1/4"
3/8"
CXE40 + CKC20
7.5
20
-
-
20
--
CXE50 + CKC40
-
15
20
-
-
20
CXE70 + CKC60
-
7.5
18
20
-
20
B. USING SUCTION AND EXPANSION LINES
The expansion assembly must be removed from the indoor unit and connected to the outdoor unit allowing a
pipe run of up to 80m, including a maximum lift of 20m (CKC20 maximum 50m with 7.5m lift).
CX(E) units only, remove the right hand panel cover plate from the indoor unit and remove the expansion
assembly. [Make good the gap using Extended Pipe Run Kit 55900709 (30,40,50), 55900710 (70).]
Fit the expansion assembly onto the outdoor unit liquid line service valve. Fully insulate both the suction and
expansion lines, including the expansion device: ensure the pipes are insulated well over the drain tray at the
indoor unit.
MAXIMUM EQUIVALENT LENGTH OF SUCTION LINE PIPE
SIZES (m)
EXPANSION LINES
SYSTEM
3/8"
1/2"
5/8"
3/4"
7/8"
3/8"
1/2"
5/8"
CX(E)30 + CKC20
7.5
23
50
-
-
50
-
-
CX(E)40 + CKC30
-
10
36
80
-
7.5
80
-
CX(E)50 + CKC50
-
7.5
18
50
80
7.5
50
80
CX(E)70 + CKC80
-
-
11
30
80
-
50
80
MAXIMUM EQUIVALENT LENGTH OF SUCTION LINE PIPE
SIZES (m)
EXPANSION LINES
SYSTEM
3/8"
1/2"
5/8"
3/4"
7/8”
3/8"
1/2"
5/8"
CXE40 + CKC20
7.5
23
50
-
-
50
-
-
CXE50 + CKC40
-
10
36
80
-
7.5
80
-
CXE70 + CKC60
-
7.5
18
50
80
7.5
50
80
PIPE CONNECTIONS
Units are supplied with the
following male flare connections
(sizes in inches):
RESTRICTORS
Indoor units are supplied with restrictors fitted.
OUTDOOR UNIT
CKC20
CKC30
CKC40
CKC50
CKC60**
CKC80
LIQUID / EXPANSION
3/8"
3/8"
3/8”
3/8"
3/8”
1/2"
SUCTION
1/2"
1/2"
1/2”
1/2"
5/8”
5/8"
NOTE
When the CXE 40 is matched with a CKC 20.
The restrictor in the indoor unit must be
changed to 0.033"
When the CXE 50 is matched with a CKC 40.
The restrictor in the indoor unit remains as
a 0.050"
When the CXE 70 is matched with a CKC 60.
The restrictor in the indoor unit must be
changed to 0.057"

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INTERCONNECTING PIPEWORK
1. The indoor unit has a low pressure charge of N2, which may be safely released into the atmosphere
before connection. The service valves on the outdoor unit should remain closed (IN, fully clockwise)
until pipework has been fitted and system evacuated.
2. Connecting the pipework
a. Remove the flare nuts from the suction and liquid service valves.
b. Ensure that the suction line is fully insulated: if an expansion line is used this should also be fully
insulated.
c. Place the flare nuts over the incoming pipework and flare the pipe ends. The use of a little
refrigeration oil on the flaring tool will help.
d. Connect the pipework between the units. Do not leave pipe ends, valves etc. open to the
atmosphere.
R407C is very hygroscopic and will absorb damaging levels of moisture if left open.
Always use two spanners when tightening the flare nuts to avoid twisting the pipes. Use a small
amount of refrigerant oil on the mating surfaces.
e. Sight glasses and filter driers are not necessary, but if required should be fitted between the
outdoor unit liquid shut off valve and the expansion device.
EVACUATING
1. Connect a vacuum pump to the service ports on the outdoor unit valves and evacuate the system to 1000
microns (1 Torr) or better and allow to be held for a minimum of 15 minutes.
2. Replace the caps on the service ports, (torque to 25NM).
ADDING REFRIGERANT
1. All units are fitted with head pressure control. The link wire across the orange terminals allows the fan
to operate at full speed. THIS SHOULD BE REMOVED AFTER CHARGING
2. If a manual HP cut-out is fitted, ensure that the reset button is depressed.
3. A 3 minute delay occurs between successive compressor operations.
4. R407C should be introduced through the Schrader valve on the indoor unit, or the service port on the
suction service valve on the outdoor unit. No other refrigerant must be used.
NOTE: LABEL R407C POE (supplied loose) TO BE FIXED ABOVE SERVICE VALVES.
CHARGE (g)
No extra POE oil needed with liquid lines.
Charges shown are for guidance: actual charge will depend on the individual application. It is recommended that
you charge to a sweat line on the outlet of the evaporator and/or a full sight glass if fitted.
Charge
based on:-
Liquid line
Expansion line
1/4"
3/8"
3/8"
1/2"
5/8"
25 g/m
60 g/m
16 g/m
30 g/m
48 g/m
Additional POE oil
25g per 350g of additional refrigerant to a maximum of 300g
NOTE: The new 20 Series CKC are supplied with a Nitrogen holding charge. See pages 11 & 12 for
refrigerant charge information.
5. Run the system for a few minutes to allow it to stabilize. Where possible, charge to a sweat line on the
evaporator. Typical suction pressure on short lines at UK conditions should be approx. 3.8bar (55 psig).
CKC REFRIGERANT

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6. Head pressure controller
The head pressure controller is factory set to suit the refrigerant. It may be necessary to adjust this to
suit site conditions, to raise or lower the nominal head pressure.
a. With the system switched off, connect a high pressure gauge to the liquid line service valve.
b. Switch on the system, and run for a few minutes to stabilise.
c. The head pressure should be approximately:
R407C: 275-280 psig (18.9-19.6barg) to achieve this remove sealing plug and insert 2mm or 5/64” allen key
into setting screw. Turn allen key clockwise (+) or counter clockwise (-) to readjust the setting. Do not turn
setting screw more than 3 turns clockwise (+3). Use following table as a quick guideline for setting:
After adjustment, re-insert sealing plug and make sure that it is properly fitted. IP65 protection requires
firmly sealed plug
NOTES:
Tolerances for condensing temperatures setpoint: ±2K
Min fan speed (0 rpm) and fan cut in pressure 200 psig (13.8 barg) are factory set and not adjustable.
NOTE: The condenser fan may stop if the operating pressure drops below 200 psig (13.8 barg)

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55908014-19
ELECTRICAL CONNECTIONS
•Cables are routed to the terminal block via the cable cord grips at the rear of the unit and then through the back of
the electrics box (see page 2).
•Cables MUST be size compatible with the recommended system fuse.
FUSES
SYSTEM
COOL ONLY
WITH ELECTRIC HEATER
1PH
3PH
1PH
3PH
CXE 30
16A
-
16A
-
CXE 40
20A
-
20A
-
CXE 50
20A
-
20A
-
CXE 70
20A
20A/PH
32A
20A/PH
Note: On 3 ph systems the supply must go to the CKC outdoor unit and then to the CXE indoor unit.
CX (NEW) CXE (NEW) CKC (NEW) 5 10 15 20
CX(E)40 + CKC20 55917002 55917016 55020720 434 734 1034 1334
CX(E)50 + CKC40 55917003 55917015 55020741 546 846 1146 1446
CX(E)70 + CKC60 55917004 55917014 55020740 940 1240 1540 1840
LIQUID LINE
R407C
SYSTEM NEW CX/NEW CKC
PART NO.
CX (NEW)
CXE (NEW)
CKC (NEW)
510 15 20 25 30 35 40 45 50 55 60 65 70 75 80
CX(E)40 + CKC20 55917002 55917016 55020720 544 624 704 784 934 1084 1234 1384 1534 1684
CX(E)50 + CKC40 55917003 55917015 55020741 656 736 886 1036 1186 1336 1486 1726 1966 2206 2356 2506 2656 2806 2956 3106
CX(E)70 + CKC60 55917004 55917014 55020740 1050 1130 1280 1430 1580 1730 1880 2030 2180 2330 2570 2810 3050 3290 3530 3770
EXPANSION LINE
R407C
SYSTEMNEW CX/NEW CKC
PART NO.
LOW TEMPERATURE MATCH
CX 17 SERIES MATCHED WITH NEW CKC 20 SERIES
CX CXE CKC 510 15 20
CX(E)30 + CKC20 55917001 55917017 55020720 679 794 909 1024
CX(E)40 + CKC30 55917002 55917016 55020730 884 1184 1484 1784
CX(E)50 + CKC50 55917003 55917015 55020722 1286 1586 1886 2186
CX(E)70 + CKC80 55917004 55917014 55020723 1410 1710 2010 2310
CX CXE CKC 20 25 30 35 40 45 50 55 60 65 70 75 80
CX(E)30 + CKC20 55917001 55917017 55020720 884 964 1044 1124 1204 1284 1364 - - - - - -
CX(E)40 + CKC30 55917002 55917016 55020730 1174 1324 1474 1624 1774 1924 2074 2224 2374 2524 2674 2824 2974
CX(E)50 + CKC50 55917003 55917015 55020722 1661 1811 1961 2111 2261 2411 2561 2801 3041 3281 3521 3761 4001
CX(E)70 + CKC80 55917004 55917014 55020723 2505 2655 2805 2955 3105 3255 3405 3645 3855 4125 4365 4605 4845
R407C
PART NUMBER
LIQUID LINE (m)
R407C
PART NUMBER
EXPANSION LINE (m)
SYSTEM
SYSTEM

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WIRING DIAGRAM
CXE

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CX

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CAREL IR33 Controller
ON/OFF SWITCH
The switch operates the fan motor and is illuminated when power is supplied to the indoor unit. When switched OFF, the
fan stops, the switch remains illuminated and the crankcase heater in the outdoor unit (if fitted) remains live.
Systems (STD)
Minimum Set
Temperatures
Indoor
Unit
Outdoor
Unit
CXE 30
CKC 20
8⁰C
CXE 40
CKC 30
8⁰C
CXE 50
CKC 50
8⁰C
CXE 70
CKC 80
8⁰C
CXEA 30
CKA 35
8⁰C
CXEA 50
CKA 35
8⁰C
CXEA 50
CKA 50
8⁰C
CXEA 70
CKA 70
8⁰C
Systems (Low Temp)
Minimum Set
Temperatures
Indoor Unit
Outdoor
Unit
CXE 40
CKC 20
4⁰C
CXE 50
CKC 40
4⁰C
CXE 70
CKC 60
4⁰C
TEMPERATURE CONTROL (Do not set the controller below 4⁰C.)
The SET temperature is factory set at 12⁰C.
The digital display normally displays the return air temperature.
To change the SET temperature, press and hold down the SET button. If no
alarms active, the ‘St1’ label appears and the current value is shown on the screen
and will flash.
To change the Setpoint value, press ▲ and ▼ keys within 60 seconds.
The display will revert to the return air temperature after 60 seconds.
The fitted de-ice thermostat will activate a de-ice cycle when there is a build up of ice
on the evaporator coil.
Cellarators will only heat a room if the electric heater option is fitted.
Displaying inputs on screen display
Press ▼ to display the current input. There are 6 inputs to select from to display
onto the screen. These are as follows:
b1: probe 1;
b2: probe 2;
di1: digital input 1;
di2; digital input 2;
St1: set point 1;
St2: set point 2;
Press ▲ and ▼ to select the input to be displayed. Press set for 3
seconds to confirm your choice.
To display the live temperature in the room you need to select
b1: probe 1
WARNING
The following actions could damage your system:
1. Switching the unit OFF and ON quickly
2. Setting the unit to HEAT and then back to COOL quickly
NB: Allow at least 3 minutes between the above actions.
CXE ELECTRONIC COOLING SYSTEM CONTROLS

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MOUNTING
Whether floor or wall mounted, it is essential that the mounting surface is capable of supporting the unit
weight. Leave space around the unit for air circulation and access for installation and maintenance.
Dimensions in mm.
1. Individual pipe runs to a maximum of 20m, including 7.5m lift, are permissible with liquid lines, 80m
with expansion lines, provided good refrigeration practice is followed.
Performance is based on 7.5m pipe runs. Correctly sized pipes for each installation will result in no
significant loss of capacity on extended pipe runs.
a) Pipe sizes are based on:-
Minimum of 3.8 m/s (750 fpm) suction gas velocity for horizontal or downflow.
Minimum of 7.6 m/s (1500 fpm) suction gas velocity for upflow.
Maximum of 15.2 m/s (3000 fpm) suction gas.
b) Where vertical risers exceed 3m, oil traps must be formed in the pipe. This will help ensure that oil
returns to the compressor. Typically fit an oil trap every 3m with a trap at the bottom of the riser.
2. In calculating equivalent lengths of pipe runs, the effect of bends and fittings must be taken into
account. The table below covers the fittings most likely to be encountered in this installation.
The equivalent lengths of all the fittings in a pipe run should be added together and the total added to
the actual pipe length in order to calculate the total equivalent length.
3. Use the shortest possible route, avoiding sharp bends.
4. Completely insulate the suction line, fully over the indoor unit drain tray.
MODEL
A
B
C
D
E
F
G
H
CKC 20
900
300
560
525
185
60
333
308
CKC 30
900
300
560
525
185
60
333
308
CKC 50
1000
300
660
570
213
60
333
308
CKC 80
1000
300
660
570
213
60
333
308
1500 min air off
100 min 100 min
600 min
CKC PIPEWORK
CKC INSTALLATION

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1
Grille
9
De-ice stat (option)
2
Fan / motor
10
Heater assembly (option)
3
Case
11
Drain stub adaptor
4
Wall / ceiling mounting brackets
12
Drain tray
5
Heater bracket
13
Side access panel
6
Coil assembly
14
Electrics box door
7
Thermostat bulb & bracket
15
Digital display (option)
8
Restrictor assembly / extended pipe (option)
Capillary Entry
Mains Cable Entry
Point
Internal Earth
Terminal
ENL
SPARE
CU
CU OUT
EN
L
MAINS IN
De - Ice
Thermostat
Capacitor
Incoming Fan
Wires
Thermostat
Switch
Digital
Temperature
Display
INSIDE VIEW OF ELECTRICS BOX
413
11
12
15
14
23
1
56
10 9
87
4
CX INDOOR UNIT COMPONENT IDENTIFICATION

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1
LID
18
FRONT ACCESS
2
CONTACTOR
19
FAN GUARD
3
OVERLOAD
20
FASCIA PANEL
4
HEAT EXCHANGER COIL
21
CORNER PANEL
5
REAR ACCESS PANEL
22
SUPPORT BRACKET
6
MAINS TERMINAL COVER
23
FAN / MOTOR ASSEMBLY
7
FAN CAPACITOR
24
END CLAMP
8
BULKHEAD PANEL
25
TERMINAL
9
HP SWITCH (MANUAL, OPTION)
26
FUSE
10
SERVICE VALVE (LIQUID)
27
FUSE TERMINAL
11
SERVICE VALVE (SUCTION)
28
TERMINAL (4 WAY)
12
VALVE PANEL
29
EARTH TERMINAL
13
BASE
30
HEAD PRESSURE CONTROL pcb
14
MOUNTING FOOT
31
3 MINUTE TIMER pcb
15
LP SWITCH
32
COMPRESSOR CAPACITOR
16
COMPRESSOR
33
ELECTRICS BOX
17
HANDLE
CKC OUTDOOR UNIT COMPONENT IDENTIFICATION
TEV LTD, ARMYTAGE ROAD, BRIGHOUSE, WESTYORKSHIRE, HD6 1QF. + 44 (0) 1484 405600 [phone]
[e-mail] www.marstair.com
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