Carrier 38UQZ016 Manual

Carier is participating in
the Eurovent Certification
Programme. Products are
as listed in the Eurovent
Directory of Certified
Products.
38UQZ 016-020-024
40ALZ 016-020-024
Split-System Air-to-Air
Heat Pumps
Installation, Operation and Maintenance Instructions

2
CONTENTS
START-UP CHECK LIST.............................................................................................................................................................. 3
PHYSICAL DATA .......................................................................................................................................................................... 4
ELECTRICAL DATA ................................................................................................................................................................... 4
DIMENSIONS ................................................................................................................................................................................. 5
Service clearance .............................................................................................................................................................................. 7
Centre of gravity coordinates.......................................................................................................................................................... 8
Weight distribution .......................................................................................................................................................................... 9
FAN PERFORMANCE CURVES .............................................................................................................................................10
PRELIMINARY CHECKS.......................................................................................................................................................... 13
Check equipment received ............................................................................................................................................................ 13
SAFETY CONSIDERATIONS................................................................................................................................................... 13
UNIT TRANSPORT, LIFTING AND HANDLING............................................................................................................... 14
UNIT INSTALLATION ............................................................................................................................................................... 14
38UQZ outdoor units.....................................................................................................................................................................14
40ALZ indoor units........................................................................................................................................................................ 16
ELECTRICAL CONNECTIONS ............................................................................................................................................... 19
REFRIGERANT LINE CONNECTIONS................................................................................................................................ 20
Connection between units ............................................................................................................................................................. 20
Refrigerant piping design ..............................................................................................................................................................21
Pipe diameter calculation procedure............................................................................................................................................21
REFRIGERANT CHARGE ....................................................................................................................................................... 23
OIL RECHARGE ......................................................................................................................................................................... 24
START-UP...................................................................................................................................................................................... 24
Initial checks.................................................................................................................................................................................... 24
UNIT COMPONENTS................................................................................................................................................................. 25
DESCRIPTION OF UNIT PROTECTION DEVICES.......................................................................................................... 25
OPERATING LIMITS ................................................................................................................................................................. 25
GENERAL MAINTENANCE.................................................................................................................................................... 26
Servicing recommendations .......................................................................................................................................................... 26
Compressor replacement............................................................................................................................................................... 27
OPTIONS/ACCESSORIES ......................................................................................................................................................... 27
FINAL RECOMMENDATIONS................................................................................................................................................ 28
TROUBLESHOOTING CHART............................................................................................................................................... 28

3
START-UP CHECK LIST Start up date: ..................................................................
Equipment sold by: ...................................................................................................................................... Contract No: .....................................................
Installed by: .................................................................................................................................................... Contract No: .....................................................
Site address: .......................................................................................................................................................................................................................................
Equipment type and serial No: 38UQZ ................................................................................................................................................................................
40ALZ..................................................................................................................................................................................
ELECTRICAL DATA:
Supply voltage Ph 1: . ........................ Volts Ph 2: .................... Volts Ph 3 .......................Volts
Nominal voltage: .............................................. Volts % network voltage: ..........................................................................................................................
Current draw Ph 1: .................................... Amperes Ph 2: ............................... Amperes Ph 3: .......................................... Amperes
Control circuit voltage: ................................... Volts Control circuit fuse: ............................................................................................. Amperes
Main circuit breaker rating: ..........................................................................................................................................................................................................
PHYSICAL DATA:
Outdoor unit 38UQZ: Indoor unit 40ALZ:
Entering air temp.: .....................................................................oC Entering air temp.: ......................................................... oC
Leaving air temp.: ......................................................................oC Leaving air temp.: .......................................................... oC
Pressure drop (air): .........................................................................kPa Pressure drop (air): ......................................................kPa
Discharge air pressure: ..................................................................... Pa Discharge air pressure: .................................................. Pa
Fan motor input: Ph. 1: .................................................Volts Fan motor input: Ph. 1: ......................................Volts
Ph. 2: .................................................Volts Ph. 2: ......................................Volts
Ph. 3: .................................................Volts Ph. 3: ......................................Volts
SAFETY DEVICE SETTING 38UQZ UNIT:
High pressure switch:cut-out: ............................................... kPa cut-in: ...............................................kPa
Low pressure switch: cut-out: ............................................... kPa cut-in: ...............................................kPa
Step controller: cut-out 1st step: ....................................oC cut-in 1st step: ................................... oC
cut-out 2nd step: ...................................oC cut-in 2 nd step: ................................ oC
Oil level: ..............................................................................................................................................................................................................................................
Oil visible in sight glass? ................................................................................................................................................................................................................
ACCESSORIES
Commissioning engineer (name): ...............................................................................................................................................................................................
Customer agreement
Name: .......................................................................................... Date: ......................................................................................................................
Remarks:
Note: Complete this start-up list at the time of installation

4
Table 1 - Physical data
Indoor unit 40ALZ 016 020 024
Outdoor unit 38UQZ 016 020 024
Cooling capacity* kW 43.3 53.5 67.0
Heating capacity** kW 45.5 57.5 78.4
Refrigerant charge (R-407C)*** kg 7.8 x 2 8.4 x 2 12.8 x 2
Outdoor unit 38UQZ 016 020 024
Weight kg 480 555 590
Compressor Reciprocating
Quantity 2 2 2
Oil charge (each) l 4.0 4.0 4.0
Oil type POE-160 PZ
Outdoor heat exchanger Copper tubes, pre-treated aluminium fins
Face area m22.29 x 2 2.29 x 2 2.29 x 2
Number of rows ... fins/m 2 ... 472 2 .. 555 3 ... 555
Test pressure bar 30 30 30
Fan Axial
Quantity 2 2 2
Nominal air flow l/s 5850 11200 10700
Refrigerant line diameters inch
Suction line 1-1/8 1-1/8 1-1/8
Liquid line 5/8 5/8 5/8
Indoor unit 40ALZ 016 020 024
Weight kg 290 305 325
Refrigerant-air heat exchanger Copper tubes, pre-treated aluminium fins
Face area m21.06 1.06 1.36
Number of rows … fins/m 4...555 6...472 6...555
Test pressure bar 30 30 30
Fan Two, double-inlet centrifugal
Nominal air flow l/s 2820 3120 3370
Air flow range l/s 2390-3250 2650-3600 2860-3880
Available static pressure (dry/wet coil) Pa 160/120 180/120 210/160
Air filter Class M1, washable
Quantity 2 2 2
Width x height mm 632 x 615 632 x 615 632 x 780
* Based on an outdoor air temperature of 35°C db and an indoor air entering temperature of 19°C wb and 27°C db.
** Based on an outdoor air temperature of 6°C wb and an indoor air entering temperature of 21°C db.
*** The refrigerant charge is for the complete system (38UQZ and 40ALZ), but excludes the refrigerant connection lines.
Table 2 - Electrical data
38UQZ-40ALZ 016 020 024
Nominal supply V-ph-Hz 230-3-50 400-3-50 230-3-50 400-3-50 230-3-50 400-3-50
Voltage range V 207-253 360-440 207-253 360-440 207-253 360-440
Nominal power input kW
Cooling* 19.77 19.77 27.50 27.50 33.90 33.90
Heating** 17.07 17.07 24.50 24.50 32.00 32.00
Nominal current drawn A
Cooling* 57.95 33.50 77.19 44.62 95.36 56.12
Heating** 52.47 30.33 68.42 39.55 91.17 52.70
Effective power input kW
Cooling* 18.64 18.64 26.36 26.36 32.50 32.50
Heating** 15.94 15.94 23.36 23.36 30.60 30.60
Effective current drawn A
Cooling* 54.64 31.59 73.99 42.77 91.42 52.84
Heating** 49.00 28.32 65.24 37.71 87.18 50.39
Starting current A 205.2 118.6 288.6 166.8 358.3 207.1
Maximum power input kW
Cooling*** 22.92 22.92 30.10 30.10 37.97 37.97
Heating+ 21.06 21.06 29.60 29.60 40.27 40.27
Maximum current drawn A
Cooling*** 65.60 37.92 83.39 48.50 105.36 60.90
Heating+ 60.55 35.00 81.62 47.18 110.93 64.12
* Based on an outdoor air temperature of 35°C db and an indoor air entering temperature of 19°C wb and 27°C db.
** Based on an outdoor air temperature of 6°C wb and an indoor air entering temperature of 21°C db.
*** Based on an outdoor air temperature of 46°C db.
+ Based on an indoor air temperature of 24°C db and an outdoor air temperature of 18°C wb.

5
1Unit support (6 fixing points, ø 19 mm)
2Suction line connecction, ø 1-1/8”
3Liquid line connection, ø 5/8”
4Cable entry
5Main disconnect switch
6Control box
7Front access panel
8Side acces panel (both sides)
9Heat echangers
0Compressors
!Fans
Fig. 1 - 38UQZ dimensions, mm
Plan view
When designing an installation, always use up-to-date drawings, available from your local Carrier office.
Side view
Rear view

6
155
B
155
680
196 350 134
C
C
405
300
405
71 252
108 307 265
99
82 80 70
25
50 605
55
1080
252 71
540
307 265
108
A
Fig. 2 - 40ALZ dimensions, mm
Access panel
Outlet
Hot water coil connections
(accessory/option)
Air
discharge
Alternative drain ø 23
See detail A
Front and right-side view
Detail A
Electrical connections
Refrigerant line
connections
Access panel
Outlet
Hot water coil connections
(accessory/option)
Air
inlet
Standard drain ø 23
See detail A
Rear and left-side view
Note: The air discharge can be changed
from horizontal to vertical (see page 17).
When designing an installation, always use up-to-date drawings, available from your local Carrier office.
Dimensions, mm
40ALZ A B C
016, 020 2125 1815 507
024 2625 2315 757

7
Fig. 3 - Service clearance, mm
38UQZ 016-024
* Required service space for the removal of the air filter and the fans (in case of a breakdown). Clearance should be the same as the unit width.
1000
500
500
(*)
600
(*)
600
40ALZ (all sizes)
Air filter removal Air filter removal
500

8
Fig. 4 - Centre of gravity coordinates (mm - approx.)
38UQZ 016-024
40ALZ (all sizes)
3
38UQZ 016 020 024
XG* 1060 1060 1070
YG* 300 340 380
ZG* 280 320 400
* Measured from point 3
40ALZ 016 020 024
XG* 1620 1625 1870
YG* 230 230 230
ZG* 520 520 520
* Measured from point 3

9
Fig. 5 - Weight distribution (kg - approx.)
38UQZ 016-024
40ALZ
Air filters
3
1
5
4
6
Point 38UQZ
016 020 024
1180 210 221
2180 210 221
329 33 36
429 33 36
531 34 38
631 34 38
Point 40ALZ
016 020 024
143 46 53
247 51 53
3100 104 110
4100 104 109

10
FAN PERFORMANCE CURVES
40ALZ 016 (standard)
Available static pressure, Pa
Air flow, l/s
Power input, kW
40ALZ 016 (high-pressure option)
Available static pressure, Pa
Air flow, l/s
Power input, kW
Indoor fan speed
Curve Pulley position Standard, r/s High-pressure option, r/s
0 Closed 17.78 21.42
1 1 17.21 20.74
2 2 16.51 19.89
3 3 15.88 19.14
4 4 15.23 18.35
Factory setting 2 16.51 19.89

11
40ALZ 020 (standard)
Indoor fan speed
Curve Pulley position Standard, r/s High-pressure option, r/s
0 Closed 20.73 24.11
1 1 20.15 23.43
2 2 19.62 22.82
3 3 19.02 22.12
4 4 18.48 21.49
Factory setting 2.5 19.32 22.47
Available static pressure, Pa
Available static pressure, Pa
Air flow, l/s
Air flow, l/s
Power input, kW
Power input, kW
40ALZ 020 (high-pressure option)

12
40ALZ 024 (standard)
Indoor fan speed
Curve Pulley position Standard, r/s High-pressure option, r/s
0 Closed 20.42 23.67
1 1 19.91 23.08
2 2 19.37 22.45
3 3 18.87 21.87
4 4 18,28 21.19
Factory setting 4 18.28 21.19
Available static pressure, Pa
Available static pressure, Pa
Power input, kW
Power input, kW
Air flow, l/s
Air flow, l/s
40ALZ 024 (high-pressure option)

13
PRELIMINARY CHECKS
Check equipment received
Carry out an external check to ensure that the units have
not been damaged during transport.
If there are any signs of damage or oil, contact the shipping
company before installing the units. Send the claim docu-
ments directly to the shipping company, stating clearly what
has been damaged. Carrier is not responsible for damage
sustained during shipment, handling and storage.
Check the contents correspond to those listed on the deli-
very note. Inform your nearest Carrier office if anything is
missing. To prevent loss or damage, do not remove the
original packaging until the unit has reached the final
installation site, where the installation must be carried out
by qualified personnel.
ATTENTION: Ensure that the unit power supply
complies with the power supply at the installation site.
SAFETY CONSIDERATIONS
Installation and servicing of air conditioning equipment can
be hazardous due to system pressure and electrical compo-
nents.
Only trained and qualified service personnel should install,
start-up or service air conditioning equipment. Untrained
personnel can perform the basic maintenance functions of
cleaning and replacing filters.
All other operations should be performed by trained service
personnel.
When working on air conditioning equipment, observe pre-
cautions in the literature, tags and labels attached to the
unit and other safety precautions that may apply.
Follow all safety codes.Wear safety glasses and work gloves.
Use a quenching cloth for unbrazing operations.
When handling or charging refrigerant, evacuating the refri-
gerant circuit, carrying out leak test, etc., ensure that ade-
quate precautions are taken.
ATTENTION - VERY IMPORTANT
• To prevent electrical shock or equipment damage, make
sure disconnects are open before electrical connections
are made. If this action is not taken, personal injury
may occur.
• Before performing service or maintenance operations
on the unit, turn off the main power switch to the
outdoor unit 38UQZ. Electrical shock could cause
personal injury.
• During unit operation, some of the refrigerant circuit
elements could reach a temperature in excess of 90°C
so only trained or qualified personnel should access
areas protected by access panels.
• The 40ALZ units are designed for ducted installation
(indoor air discharge). If ducts are not used the
installer must place a protection grille in the discharge.
• Moving, lifting, transporting and positioning the
units must be done with all outside panels installed.
• Move and position the units with care.
• Do not start up the units until all electrical and refri-
gerant connections have been made and the system has
been charged with the necessary oil and refrigerant
quantity.
• Ensure that the equipment used to move the units is
appropriate for the unit weight.
• The location or base on which the 38UQZ outdoor
units are installed must be able to support the operat-
ing weight of these units.
The system used to fix or support the 40ALZ indoor
units must also be able to support their weight.
• The units are supplied with a dry nitrogen holding
charge which must be removed before making the
refrigerant line connections and charging the units.
• The 38UQZ and 40ALZ units should not be installed
in an explosive atmosphere.
• The unit can operate in normal radioelectric atmo-
spheres in residential, commercial and light industrial
installations.
For other applications check the electromagnetic
radiation around the units. The units are tested in
accordance with applicable standards on electromag-
netic compatibility.
• Do not connect R-22 units to R-407C units, e.g. do
not connect a 38UQ outdoor unit to a 40ALZ indoor
unit or a 38UQZ to a 40AL.

14
UNIT TRANSPORT, LIFTING AND HANDLING
• Ensure the lifting and transport equipment used is
able to support the unit weight (see Table 1).
• When rigging, use spreaders to prevent damage to the
panels (see Figs. 6 and 7).
40ALZ models
• Insert protective material between the lifting cables
and the casing.
Fig. 6
Protective
material
Spreaders
Spreaders
Base
See detail
Base
UNIT INSTALLATION
38UQZ outdoor units
Clearance between units, walls and other objects
These units have been designed for outdoor installation.
IMPORTANT: It is not possible to connect outdoor
supply and return air ducts to the 38UQZ outdoor units.
• The surface on which the units are mounted must be
able to support the unit weight (See Table 1 - Physical
Data).
• Leave sufficient clearance around the unit for service
and maintenance (see Fig. 3).
• Select a location free of dust or foreign matter which
may cause coil clogging.
• Leave sufficient clearance for free air circulation
(outdoor supply and return air).
• For minimum clearances between the units and walls
or roofs, see Figs. 8, 9 and 10.
Fig. 8 - 38UQZ 016-024
Rigging hook
FRONT VIEW
PLAN VIEW
Supply air
Return air
38UQZ models
Fig. 7
FLOOR
Return air
ROOF
Control
box
Return air
Table 3 - Minimum clearances (mm)
A C*
500 Free
* There must not be any obstacle, ceiling or roof near the unit.
• If several units are installed close to each other in the
same area, ensure the minimum clearance between
them to allow free air flow.
• The clearance between the units must be sufficient to
ensure that the discharge air from one unit does not
mix with the supply air of another unit.
ATTENTION
• To prevent transport damage, do not unpack the units
until they have reached their final location.
• Never roll or tip the unit more than 5°.
• Do not remove the plastic packing material from the
38UQZ units until they have reached their final
location. This protects the units from dust in the
atmosphere.
• The 40ALZ units must also be protected by plastic
packing material until they reach their final location.
IMPORTANT: Make sure that all unit panels are fixed in
place before moving. Raise and set down the unit carefully.

15
Fig. 9 - 38UQZ 016-024
• The air enters through three sides and is discharged
through the top.
Table 4 - Minimum clearances between units (mm)
38UQZ A B C
016-024 500 700 500
Fig. 10 - 38UQZ 016-024
• The air enters through three sides and is discharged
through the top.
Table 5 - Minimum clearances between units (mm)
38UQZ A B C
016-024 500 700 500
Installation on the ground
• 38UQZ units can be positioned on the floor of a patio,
on the ground or on a lawn. If installed on the ground
or on the lawn they should be mounted on a 100 mm
high concrete base that is 100 mm larger than the base
unit on all four sides.
Return air
Return air
Return air
Return air
PLAN VIEW
PLAN VIEW
Return air
Return air
Return air
Return air
Return air
Return air
Return air

16
• If this type of installation is used, ensure that the units
are not affected by flooding, snow accumulation or
leaves.
• Ensure that the units are secured to prevent injuries
to people handling or working on the units.
IMPORTANT: Rainwater, and in heat pump mode defrost
water, is drained through the unit base. For this reason the
units must be elevated above the concrete base to allow
correct drainage.
• Rainwater and defrost water drainage
38UQZ units incorporate drillholes in the base in
order to correctly drain any condensate or rainwater
and defrost water which may enter the unit in the fan
area. Ensure correct drainage.
• Provide suitable vibration isolators to prevent noise
transmission and vibrations during unit operation.
Fig. 12
• The 38UQZ models incorporate fixing holes in the
base profile to attach the units to the floor.
• 38UQZ models can have several vibration isolator
types, as shown in Fig. 13.
IMPORTANT: Units must be installed in accordance with
applicable local, national and European installation and
safety standards and regulations.
40ALZ indoor units
These units have been designed for indoor installation,
connected to supply and return air ducts.
When selecting the installation site, observe the following
points:
• Ensure that the condensate water collected in the drain
pan is correctly evacuated.
• Leave sufficient clearance for installation and mainte-
nance (see Fig. 3 - Service clearances).
• If the units are not ducted, ensure that the return air is
sufficient for the required air flow.
• See Table 1 - Physical Data, for unit weights and ensure
that the installation surface can support the unit weight.
• In accordance with applicable standards and laws the
unit can be suspended from the ceiling or floor-mounted
(see Fig. 14).
Fig. 14
Vibration isolators
Vibration isolators
Unit
Hexagonal nut
Washer
Flexible mounting
Base
Unit
Flexible mounting
Washer
Spring washer
Hexagonal nut
PNL 40 x 40 x 4 PNU 80 x 45 x 6
100 mm
Concrete base
ROOF
Supply
air
Supply
air
ROOF
Vibration isolators
Base
Fig. 13Fig. 11
Concrete base

17
The units leave the factory with the air discharge set to hori-
zontal. It can be changed to vertical discharge by following
the steps below.
Change from horizontal (standard) to vertical discharge with
changing the position of the motor. See Fig.15, depending
on model.
a) Detach the side access panels 1.
b) Remove the drive belt(s) 6.
c) Unscrew the fans from the brackets 4securing them
to the base.
d) Detach the rear panel with the fan outlets 2and the
top panel 3.
e) Detach the tension base together with the motor 9and
position it on the opposite side from where it was.
f) Remove the fan pulley 1and reposition it on the other
side.
g) Interchange the position of panels 2and 3, fastening
them correctly to the unit.
h) Bolt the U-bracket 4to each fan.
i) Bolt the U-bracket 5to the angle iron 4holding the
fans to the base.
j) Replace the drive belt(s) and ensure that the tension
is correct.
k) Replace the access panels 1.
Fig. 15 - Repositioning unit air discharge (40ALZ)
Supply
air
Return
air Return
air
Supply
air
Return
air
Supply
air
Return
air Return
air
Supply
air
Legend
1 Side access panel 6Drive belt(s)
2Rear discharge panel 7Roof panel
3Top panel 8Fan pulley
4Angle iron to attach fan to base 9Base
5U-bracket
Condensate drainage
40ALZ units are supplied with a condensate drain pan with
two drain pipes (outside diameter 23 mm).These tubes leave
the factory separately wrapped so it is easy to check them.
The connection to the drain pipe can be vertical (see Fig. 16)
or horizontal (see Fig. 17).
• Vertical drain: Remove the prepunched knockout(s)
in the unit base.
• Horizontal drain: Drainage through holes in the side
of the unit base, to the right- or left-hand side.
Fig. 16 - Vertical drain
Drain pipe 23
mm OD Hole in unit base
Interior drain
pan
Unit base
75 mm
100 mm
Field-supplied
trap
Fig. 17 - Horizontal drain
Drain pipe 23
mm OD Outlet panel, unit side
Interior drain pan
Unit base
Field-supplied
trap
75 mm
100 mm
The field-installed trap must be below the drain pan.
The drain pipe must never be higher than the drain pan.
Fig. 18
Supply
air
Return
air
YES
NO

18
Ductwork
The ductwork dimensions should be determined in accor-
dance with the air flow to be carried, and the available static
pressure of the unit.The different air flows and power input
values for each unit are shown in the fan performance curves.
It is recommended to observe the following considerations:
a) Whatever type of ductwork is used, it should not be
made of materials which are flammable, or which give
off toxic gases in the event of a fire. The internal sur-
faces should be smooth, and not contaminate the air
which passes through.
b) At the points where the ducts join the unit, it is recom-
mended to use flexible connections which absorb
vibrations, prevent noise inside the ductwork and allow
access to the unit (see Fig. 19).
c) Bends near the unit outlet should be avoided as much
as possible. If unavoidable, they should be as slight as
possible, and internal deflectors should be used when
the duct has large dimensions.
d) The installation of baffles in the supply air outlet ducts
significantly dampens the noise created by the air flow.
e) The ratio between the duct sides should not exceed
1:3 (rectangular ducts).
Fig. 19 - Side view
Fan pulley
2 kg or 3 kg
Motor
pulley
Align the pulleys using a ruler.
Fig. 21
To align fan and motor pulleys:
1. Loosen fan pulley setscrews. Slide fan pulley along the
pulley shaft and align with the motor using a ruler,
making sure that it is parallel to the belt (see Fig. 21).
2. Tighten the fan pulley setscrews.
To adjust the belt tension, loosen the motor mounting
plate bolts and slide the motor mounting plate until the
belt is tight.
3. Belt tension (see Fig. 22)
The minimum belt deflection is 10 mm when the force
shown in Fig. 22 is applied.
Fig. 22
Legend
1 Fixed flange
2 Setscrews
3 Movable flange
4 Straight-edge must be parallel with belt
5 Motor and fan shafts must be parallel
6 Pulleys
7 Motor and fan shafts must be parallel
Motor support
Motor pulley
Motor
Belt
Tensioning screw
Setscrews
Flexible joint
Return
air
Supply
air
Unit
f) Adjust the belts and pulleys to obtain air flows and
static pressures that differ from the nominal values, if
required.
The units are factory-set to supply nominal air flow and
nominal static pressure, as shown in the fan performance
curves.
When indoor pressure and air flow requirements differ
from nominal ratings, the motor pulley can be adjusted for
different available static pressure values:
1. Move the motor along its track in order to remove the
belt (see Fig. 20).
2. Loosen the pulley setscrews and rotate as necessary
(see fan performance curves).
3. Tighten the setscrews.
4. Replace the belt(s) in the channel of the pulley.
5. Tighten the belt(s), using the tension screw nut and
washer (see Fig. 21).
6. Check the new fan speeds with a tachometer.
7. After the first operating hours, check the belt tension
and if necessary retighten the belts (see Fig. 21).
Fig. 20

19
ATTENTION: Once the motor pulley opening or closing
has been set, check that the setscrews have been correctly
tightened.
ELECTRICAL CONNECTIONS
WARNING: To prevent electrical shock or equipment
damage, make sure disconnects are open before electrical
connections are made. If this action is not taken, personal
injury may occur.
NOTE: The power supply for the units has to be in accor-
dance with applicable standards and laws, the low voltage
directive, etc.
• Connect the power supply for the complete system
(outdoor unit and indoor unit) via the 38UQZ outdoor
unit (see Fig. 23).
• Consult the wiring diagram supplied with the unit, that
shows all power connections between the 38UQZ out-
door unit and the 40ALZ indoor unit and the general
power supply to the system.
• The connection cables between the units must not be
lighter than the flexible Neoprene-covered cable (type
H05 RN-F), with an appropriate wire section for the
supply to the 40ALZ unit.
• The power of the optional electric heater of the indoor
unit is supplied via the main disconnect switch of the
38UQZ unit (see Fig. 1).
Fig. 23 - General unit power supply
Legend
Q1: Main unit power supply disconnect switch.
Located in the outer panel of the 38UQZ unit.
F1: Field-installed fuses.
• Route all cables through the conduits in the 38UQZ
units to the terminals of the main disconnect switch
(see unit wiring diagram).
• Voltage to the unit must be within 10% of the nominal
given in the electrical data table with a maximum phase
imbalance of 2%. Contact your local power company
for correction of an incorrect line voltage.
• Take special care when making the earth connection.
This is the first cable to be connected, and it must be
longer than the live cables.
• Operation of the unit on improper line voltage consti-
tutes abuse and is not covered by the Carrier warranty.
IMPORTANT: To ensure the correct unit power supply it
is necessary first to determine the wire section. The unit
electrical data (see Table 2 - Electrical Data) and the line
length (max. admissible voltage loss 5%) must be taken
into consideration.
If the indoor unit includes an electric heater, this must be
taken into consideration when sizing the system power
supply cable (38UQZ-40ALZ) and the isolator switch
and fuses.
• Never operate a unit if the voltage imbalance exceeds
10%.The following formula must be used to determine
the percentage of voltage imbalance.
Voltage imbalance % =
Largest deviation from average voltage
Average voltage
Example: Nominal supply: 400-3-50
AB = 404 V
BC = 399 V
AC = 394 V
Average voltage = 404 + 399 + 394 = 399 = 400 V
3
Determine maximum deviation from average voltage:
AB = 404 - 400 = 4
BC = 400 - 399 = 1
AC = 400 - 394 = 6
Largest deviation is 6 volts. Percentage voltage imbalance
is therefore:
6 x 100 = 1.5 %
400
• The cables marked 1from the 40ALZ indoor units
are run to the 38UQZ outdoor unit control box for
connection to the fan motor, and in the case of the
optional electric heater also cables marked 2.

20
Legend
F8 Thermomagnetic indoor fan switch (included in the control box).
K3 Indoor fan motor contactor (included in the control box).
F4 Indoor fan motor thermal protection (included in the control box).
F1 General fuses of the installation (field-supplied).
Q1 Unit main disconnect switch (included in the 38UQZ panel).
F19 Thermomagnetic switch of the optional electric heater.
K6 Optional electric heater contactor.
R1, R2 Optional crankcase heater.
F6 Thermomagnetic switch of the optional crankcase heater.
M 40ALZ indoor fan motor.
1Connection cables between the 40ALZ indoor unit fan motor and the
38UQZ control box.
2Cables from the 40ALZ unit of the outdoor unit for the power supply of the
heating coil.
NOTE: The cables shown by the broken lines are not factory-supplied.
• If the units include options or accessories, such as
heating coils for electric heaters or the compressor
crankcase heater, proceed as follows:
Heating coils for electric heater - connect in accordance
with the wiring diagram downstream of the 38UQZ
main disconnect switch. Do not exceed the power in
kW recommended by Carrier. Use correctly sized main
fuses and the new unit power supply cable section. If
the power input of the electric heater plus the power
input of the indoor and outdoor fan plus the power
input of the compressor is higher than the total power
input given in Table 2 - Electrical Data, new fuses and
power supply cable sections must be used.
• Thermostat connection
Thermostat/unit connection must be via a loom manu-
factured in accordance with the wiring diagram accom-
panying the unit and the thermostat installation
instruction.
NOTE: Refer to the applicable thermostat installation manuals for each model.
REFRIGERANT LINE CONNECTIONS
Connection between units
The 38UQZ outdoor units must be connected with the
40ALZ indoor units with refrigerant-grade copper pipes
for correct operation.
For each compressor in the 38UQZ outdoor unit a pipe for
refrigerant gas and another pipe for liquid refrigerant must
be installed.
For copper-pipe refrigerant connection lines the following
points must be observed:
• Ensure that the line length is as short as possible.
• The number of bends or elbows must be the minimum
possible.
• Design the lines with the correct diameter for the
required compressor oil suction velocity.
• Route the lines so that they do not obstruct the normal
building use. Avoid exposing them to extreme high or
low temperatures.
• Install them where they cannot be damaged.
• If they are routed outside the building, protect them
against extreme temperatures and damaging environ-
mental influences.
• Insulate the suction/discharge line along its complete
length, and the liquid line if this is indicated.
IMPORTANT: Always use refrigerant-grade deoxidized
and dehydrated copper tubing between the indoor and
outdoor units.
• Carefully protect the copper pipes during transport,
installation and connection, against possible ingression
of water or moisture.
• Also prevent entry of any contaminants or foreign
substances.
• Four operations are very important:
- Pipe cleaning
- Pipe leak tightness
- Correct leak tests
- Correct evacuation
• When pipes are soldered, cut or flared, etc. ensure that
no residue or shavings can enter the pipes. Blow any
residue away from the pipe ends and check them
carefully.
Fig. 24
Crankcase heater