Marstair 550 series User manual

55008279-16
INSTALLATION INSTRUCTION
550 SERIES CONDENSING UNITS AND 551 SERIES HEAT PUMP OUTDOOR UNITS

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GENERAL
MOUNTING
These units are designed to stand on a flat surface. If the unit is to be wall mounted the following kits are
available.
KIT
MCU+ 15-80 / MHPUE 15 / 60
MCU+ 90-200 / MHPUE 80-180
Mounting Bracket
55021100
55021101
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. 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. These units are supplied pre-charged with R407C refrigerant and polyolester oil.
Do not open the valves until the system is fully installed.
Do not mix oils and refrigerants.
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 outdoor unit. For system details add input power and
current of indoor and outdoor unit, including any heater load.
5. FUSES- for recommended fuse size see indoor unit instructions.
1500 min air off
100 min 100 min
600 min

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DIMENSIONS & WEIGHTS
MCU+ 15-100 & MHPUE 15-90 (Dimensions in mm.)
MODEL
A
B
C
D
E
F
G
H
Weight (kg)
1 Ph
3 Ph
MCU+ 15
900
300
560
525
185
60
295
275
45
--
MCU+ 20
900
300
560
525
185
60
295
275
46
--
MCU+ 30
900
300
560
525
185
60
295
275
48
48
MCU+ 40
900
300
560
525
185
60
295
275
53
53
MCU+ 50
1000
300
660
570
213
60
295
275
64
62
MCU+ 60
1000
300
660
570
213
60
295
275
65
63
MCU+ 80
1000
300
660
570
213
60
295
275
66
64
MCU+ 90
1000
350
760
495
250
70
345
325
76
73
MCU+ 100
1000
350
760
495
250
70
345
325
--
81
MHPUE 15
900
300
560
525
185
60
295
275
47
--
MHPUE 30
900
300
560
525
185
60
295
275
50
50
MHPUE 40
1000
300
660
570
213
60
295
275
61
61
MHPUE 50
1000
300
660
570
213
60
295
275
64
62
MHPUE 60
1000
300
660
570
213
60
295
275
68
66
MHPUE 80
1000
350
760
495
250
70
345
325
75
72
MHPUE 90
1000
350
760
495
250
70
345
325
77
75
MOUNTING
HOLES
H
G

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MCU+ 130 - 200 and MHPUE 100 –180 (Dimensions in mm.)
MODEL
A
B
C
D
E
Weight (kg)
MCU+ 130
1000
1020
495
251
100
101
MCU+ 150
1000
1020
495
251
100
103
MCU+ 165
1000
1020
495
251
100
103
MCU+ 180
1100
1215
675
211
95
118
MCU+ 200
1100
1215
675
211
95
173
MHPUE 100
1000
1020
495
251
100
101
MHPUE 130
1000
1020
495
251
100
102
MHPUE 150
1000
1020
675
211
95
106
MHPUE 165
1100
1215
675
211
95
120
MHPUE 180
1100
1215
675
211
95
122
PIPEWORK
Supplied male flare connections (sizes in inches)
Model
MCU+
Size
15
20
30
40
50
60
80
90
100
130
150
165
180
200
Expansion
3/8
3/8
3/8
3/8
3/8
3/8
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
Suction
3/8
3/8
1/2
1/2
1/2
5/8
5/8
5/8
3/4
3/4
3/4
3/4
7/8*
7/8*
Model
MHPUE
Size
15
30
40
50
60
80
90
100
130
150
165
180
Expansion
3/8
3/8
3/8
3/8
3/8
1/2
1/2
1/2
1/2
1/2
1/2
1/2
Suction
3/8
1/2
1/2
1/2
5/8
5/8
3/4
3/4
3/4
3/4
7/8*
7/8*
* Brazed connections
MAXIMUM PIPE RUNS
80m maximum (MCU+ 15-20 = 50M) including 20m lift. There will be no significant loss of capacity for
extended pipe runs provided pipes are correctly sized and the correct restrictor is fitted.
A
CDE
B
60
10
417
397
425
MOUNTING
HOLES

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CALCULATING EQUIVALENT LENGTHS
The effects of bends and fittings must be taken into account. The table on top of page 5 covers the fittings
most likely to be encountered in installation.
ACTUAL PIPE LENGTH + TOTAL EQUIVALENT FITTING LENGTHS = TOTAL EQUIVALENT LENGTH
FITTING LOSSES in equivalent straight lengths of pipes (m)
Pipe sizes are based on:
Minimum of 2.5 m/s (500 fpm) suction gas velocity for horizontal or downflow.
Minimum of 5.0 m/s (1000 fpm) suction gas velocity for upflow.
Maximum of 20.0 m/s (4000 fpm) suction gas.
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.
GOOD PRACTICE
Keep pipe runs as short as possible.
Avoid sharp bends
Fully insulate both suction and expansion including mechanical connections
Try to avoid running pipes through hot areas.
PIPE SIZES
UNIT
MAXIMUM LENGTH OF EQUIVALENT
SUCTION LINE PIPE SIZES (m)
EXPANSION LINES
FACTORY CHARGE
FOR 7.5M RUNS
AT UK
CONDITIONS (g)
⅜
½
⅝
¾
⅞
1⅛
1⅜
⅜
½
⅝
¾
R407C
MCU+ 15
7.5
30
50
50
660
MCU+ 20
7.5
23
50
50
1030
MCU+ 30
15
50
80
50
80
1000
MCU+ 40
10
36
80
7.5
80
1240
MCU+ 50
7.5
18
50
80
7.5
50
80
1690
MCU+ 60
14
36
80
7.5
50
80
2000
MCU+ 80
11
30
80
50
80
1880
MCU+ 90
10
25
55
80
20
80
2060
MCU+ 100
7.5
22
45
80
15
80
2520
MCU+ 130
15
30
80
12
60
80
4170
MCU+ 150
12
27
80
8
50
80
4170
MCU+ 165
8
18
60
80
7.5
40
80
4540
MCU+ 180
7.5
16
55
80
7.5
35
80
4640
MCU+ 200
15
50
80
7.5
30
80
5480
MHPUE 15
7.5
30
50
50
800
MHPUE 30
15
50
80
50
80
900
MHPUE 40
10
36
80
7.5
80
1600
MHPUE 50
7.5
18
50
80
7.5
50
80
1660
MHPUE 60
14
36
80
7.5
50
80
1590
MHPUE 80
11
30
80
50
80
1780
MHPUE 90
25
55
80
20
60
80
2260
MHPUE 100
22
45
80
15
50
80
3380
MHPUE 130
15
30
80
12
60
80
4470
MHPUE 150
12
27
80
8
50
80
4200
MHPUE 165
7.5
18
60
80
7.5
40
80
4650
MHPUE 180
16
55
80
7.5
35
80
5620
FITTING
PIPE SIZE (outside diameter in inches)
INSTALLERS TABLE
Nº OF
FITTINGS
EFFECTIVE
LENGTH
⅜
½
⅝
¾
⅞
1⅛
45° Bend
0.12
0.15
0.18
0.21
0.24
0.30
90° Bend R/d = 1
0.37
0.43
0.49
0.55
0.61
0.79
90° Bend R/d = 2
0.24
0.27
0.30
0.37
0.43
0.52
180° Bend C/d = 1
0.73
0.91
1.10
1.28
1.46
1.83
180° Bend C/d = 2
0.46
0.55
0.64
0.76
0.85
1.07
90° Elbow
0.67
0.85
1.04
1.25
1.46
1.89
R = Radius of bend
d = Diameter of tube
C = Centres of bend
TOTAL =

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RESTRICTORS
Outdoor units (cool only & heat pumps) are supplied with expansion assemblies and cooling restrictors fitted.
MCU+
15
20
30
40
45
50
60
80
90
100
130
150
165
180
200
Restrictor
0.033
0.033
0.040
0.044
0.046
0.050
0.052
0.057
0.063
0.068
0.071
0.080
0.082
N/A
HEAT PUMP HEATING
All heat pump units have an additional expansion assembly supplied loose inside the unit. This is to be
fitted to some indoor units for heating. Fit the assembly within 10m of the indoor unit in the expansion
line.
Note: the refrigerant flow is from indoor to outdoor, opposite to cooling assembly. Placing it directly at
the indoor coil may cause increased noise during the heating cycle. No separate check valve is
needed. The expansion assembly and line must be fully insulated.
Note: The indoor units listed below are fitted with heating capillarys.
WM60H, WM80H, WM100H, CC875/80H, CC875/110H, CC875/140H, HL380, HL460, HL540
The additional heating expansion assembly (supplied loose in the heat pump unit) is not required.
Retain as a spare.
MHPUE(L)
15
20
30
40
45
50
60
80
90
100
130
150
165
180
RestrictorCooling
0.033
0.037
0.040
0.044
0.046
0.052
0.055
0.058
0.065
0.068
0.076
0.079
N/A
RestrictorHeating
0.035
0.036
0.039
0.042
0.043
0.043
0.053
0.053
0.058
0.083
0.092
0.093
N/A
CONNECTING THE UNITS
1. Ensure both service valves on the unit are closed (clockwise) before
commencing installation.
2. If the cooling restrictor is to be changed:
a. Remove the entire expansion assembly from the outdoor unit.
b. Split the expansion assembly in the middle and remove the existing
restrictor.
c. Drop the new restrictor vertically into the field connector.
d. Reassemble in the vertical plane (field connector lowest) when
reassembled the restrictor can be heard to be free to move if the
assembly is shaken.
e. Refit the expansion assembly.
3. Connecting the pipework:
a. Remove the flare nuts from the suction service valve and the expansion device as appropriate.
b. Ensure that both the suction and expansion lines are fully insulated.
c. Place the flare nuts over the incoming pipework and flare the pipe ends.
d. Connect the pipework between the units. Do not leave pipes ends, valves etc open to the
atmosphere. Always use 2 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 filters driers are not necessary, but if required should be fitted between the out
door unit liquid shut off valve and the expansion device on the MCU+ units.
f. MCU+ 180 & 200 and MHPUE 165 & 180 have a ⅞¨ suction pipe with brazed connections. Use a
protective shield to avoid scorching the side panel.
EVACUATING
With the valves closed, connect a vacuum pump to the service ports on the outdoor unit valves. Evacuate
the interconnecting pipework and indoor unit to 1000 microns (1 Torr) or better. Allow this to be held for a
minimum of 15 minutes
REFRIGERANT FLOW
RESTRICTOR

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ELECTRICAL
The installer supplies mains, control and interconnecting cables: equipment must be earthed.
Wiring must be carried out in accordance with local and national codes.
Interconnecting wiring diagrams are in the indoor unit installation instructions.
Mains supply cables must be size compatible with the recommended fuse (see indoor unit instructions).
An all pole isolator switch should be positioned within easy reach of the indoor unit.
Cable clamps for use with stranded cables are supplied in units 15 - 90 and should be used to secure
incoming/outgoing cables. Installers must supply a method of securing solid sheathed cables.
THREE PHASE UNITS WITH SCROLL COMPRESSORS:
On 3 Ph units sizes 50 - 200 it is possible for the scroll compressor to run backwards.
This becomes obvious on start up - the compressor will not develop a normal running pressure differential
and the top will not become warm: it may be excessively noisy. If this happens, switch off the mains power
and exchange the two supply phases not connected to the indoor unit. This will correct the rotation.
SYSTEMS INCLUDING AN ELECTROMECHANICAL UNIT:
These require a supply to the outdoor unit with connecting cables run to the indoor unit.
ELECTRONIC SYSTEMS (INDOOR 'E' MATCHED WITH MHPUE):
It is recommended that these systems have a supply taken to the outdoor unit and a separate supply taken
to the indoor unit, which in many cases can be from a domestic 13 Amp socket. If a 1ph system is being run
from a 3ph supply ensure that both units are supplied from the same phase.
Otherwise run a supply to the outdoor unit with connecting cables run to the indoor unit.
Communication between indoor and outdoor electronic units is via a two wire (max. 0.75mm2) non-polarised
connection (installer supplied), using cable type RS 485 or equivalent (e.g. two cores of 00526077, 4 core
cable, available from TEV). The cable screen must be secured to ground (earth) at both ends using the
clamps provided.
Do not attempt to run the communication in the spare cores of any power carrying cable.
Alarm terminal 5: this terminal is live (230V L1) when a fault is present. Load range is 2W- 100W (loads
less than 2W may indicate false alarms). External alarm loads must be returned to the system neutral.
ISOLATOR SWITCHES:
On 3 phase systems ensure that the neutral contact of the isolator switch is an early make, late break type.
This applies to all switches in the supply line. Failure to observe this could result in damage to the
electronic board. If in doubt, do not switch the neutral but connect it solidly.
1PH FUSE SIZE
MCU(+)
30
40
50
60
80
90
100
130
150
165
180
200
FUSE
16
20
16
20
25
32
-
-
-
-
-
-
3PH FUSE SIZE
MCU(+)
30
40
50
60
80
90
100
130
150
165
180
200
FUSE
10
10
10
10
10
16
16
16
20
20
25
32

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REFRIGERANT
IF NO ADDITIONAL REFRIGERANT CHARGE IS REQUIRED:
Open the valves very slowly using a 5 or 8mm Allen key. On MHPUE units, remove link JP6 on the pcba
(identified by a white label), otherwise the fan will always run at maximum speed and the infrared handset
will be inoperative. Replace the caps on the service ports, (torque to 25NM).
IF ADDITIONAL REFRIGERANT IS REQUIRED:
1. After evacuating the indoor unit and interconnecting pipework, slowly open the valves using 5 or 8mm
Allen key. The high and low pressure should equalise within a minute.
2. Additional charge should be introduced with the system running in the air conditioning mode
(including heat pumps). See indoor unit instruction for additional system charge.
3. MCU+ 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
ADDITIONAL REFRIGERANT - pipe runs over 7.5m.
Add refrigerant and oil for each additional metre over 7.5m, based on the following:
Expansion line size.
3/8"
1/2"
5/8"
Additional polyolester oil:
L’Unite 181-023,
ICI Emkarate RL32S or
RL32CF, Mobil Arctic
EAL22 or EAL22C.
Additional refrigerant (g/m).
16
30
48
Additional POE oil
25g per 350g of additional
refrigerant to a maximum of 300g
4. MHPUE:
These are supplied with link JP6 fitted on the pcba; this allows additional charging and overrides
alarms during the charging process. With both units powered, the MHPUE fans will run at high speed.
After charging, remove link JP6 on the pcba (identified by a white label), otherwise the fan will run
at maximum speed.
5. If a manual HP cutout is fitted, ensure that the reset button is depressed.
6. MHPUE:A random start delay of up to 1 minute occurs when mains is first applied.
A 3 minute delay occurs between successive compressor operations on all MCU+ and MHPUE
systems.
7. Additional refrigerant and polyolester oil should be introduced through the Schrader valve on the
indoor unit, or the service port on the suction service valve on the outdoor unit. Ensure the
refrigerant is the correct type, as shown on the rating plate. R407C must always be added in the
liquid state.
8. Run the system for a few minutes to allow it to stabilize. Where possible, charge to a sweat line on the
evaporator. Typical suction pressures on short lines at UK conditions, with high speed evaporator fan,
high speed condenser fan (commissioning speed for MHPUE), should be; electromechanical comfort
system approx 4.4 bar (65 psig); electronic comfort system approx 3.8 bar (55 psig); heat pump
system approx (58 psig). Systems should not be overcharged, to avoid liquid return to the
compressor.
9. MCU+: HEAD PRESSURE CONTROL SAGINOMIYA (RGE –ZIN4 –SH)
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.

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a. With the system switched off, connect a high pressure gauge to the liquid line service valve.
b. Switch on the system, indoor fan set to high speed, and run for a few minutes to stabilise.
c. The head pressure should be approximately:
Electricsbox
Headpressure
adjustmentscrew
Fancapacitor
R407C: 275-280 psig (18.9-19.6barg) to achieve this adjust the screw clockwise to increase pressure
or anticlockwise to decrease. Each ½ turn will alter the pressure by approx 5 psig (0.5 barg)
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)
10. HEAD PRESSURE CONTROL ALCO (FSY-42S) & SAGINOMIYA (XGE-4C)
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.
ALCO (FSY-42S)
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:
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)
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:

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Pressure changes per turn of adjusting screw:
Pressure change: 9.2 … 21.2 bar:
Clockwise ~ +2,5 bar, counter clockwise ~ -2,5 bar
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
SAGINOMIYA (XGE-4C)
R407C: 275-280 psig (18.9-19.6barg) to achieve this turn the range adjusting screw clockwise (+)
for increasing the setting value or counter clockwise (-) for decreasing the setting value.
Pressure changes per 1 turn of adjusting screw:
Pressure change: 10 … 25bar:
Clockwise ~ +1.5 bar, counter clockwise ~ -1.5 bar
TEV LTD,ARMYTAGE ROAD, BRIGHOUSE, WESTYORKSHIRE, HD6 1QF. + 44 (0) 1484 405600 [phone]
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