Comfortaire Century VFH-B Series User manual

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Service Manual
VFH-B Series
Inverter Multi Zone Ductless Mini-Split
A-VFH18DB-1
A-VFH24TB-1

Service Manual - VFH-B 18/24 Series
2

Service Manual - VFH-B 18/24 Series
3
Table of Contents
Part Ė: Technical Information.......................................................................4
1. Summary......................................................................................................................4
6SHFL¿FDWLRQV..........................................................................................................5
3.
Outline Dimension Diagram..........................................................................9
4.
Refrigerant System Diagram......................................................................10
5.
Electrical Part...........................................................................................................11
5.1 Wiring Diagram................................................................................................................11
5.2 PCB Printed Diagram ......................................................................................................13
6.
Function and Control.........................................................................................15
Part ė: Installation and Maintenance .................................................18
7.
Notes for Installation and Maintenance............................................18
8.
Installation Manual..............................................................................................20
8.1 Electrical Connections.....................................................................................................21
8.2 Installing the Outdoor Unit...............................................................................................22
8.3 Installation Dimension Diagram.......................................................................................23
8.4 Check after Installation....................................................................................................24
9.
Troubleshooting....................................................................................................25
9.1 Flashing LED of Indoor/Outdoor Unit and Primary Judgement ......................................25
9.2 Malfunction Checking and Elimination ............................................................................26
9.3 Maintenance Method for Normal Malfunction..................................................................39
10.
Exploded View and Parts List
................................................................41
11.
Removal Procedure.........................................................................................45
Appendix:........................................................................................................................58
Appendix 1: Reference Sheet of Celsius and Fahrenheit ....................................................58
$SSHQGL[&RQ¿JXUDWLRQRI&RQQHFWLRQ3LSH.....................................................................58
Appendix 3: Pipe Expanding Method ...................................................................................59
Appendix 4: List of Resistance for Temperature Sensor ......................................................60

Service Manual - VFH-B 18/24 Series
4
1. Summary
Part Ė: Technical Information
Outdoor Unit
A-VFH18DB-1
A-VFH24TB-1

Service Manual - VFH-B 18/24 Series
5
Model A-VFH18DB-1
Product Code CB228W07700_L61437
Power
supply
Rated Voltage V~ 208/230
Rated Frequency Hz 60
Phases 1
Cooling capacity(max~min) Btu/h 18000(6155~6998)
Heating capacity(max~min) Btu/h 19000(8530~22600)
Cooling Power Input(max~min) W 1440
Heating Power Input(max~min) W 1520
Cooling Current Input A 6.26
Heating Current Input A 6.61
Rated Power Input W 2800
Rated Current A 12.42
EER (Btu/h)/W 12.5
COP (Btu/h)/W 12.5
Outdoor
Unit
Compressor Trademark ZHUHAI LANDA COMPRESSOR CO.,LTD
Compressor Model QXA-B141zF030A
Compressor Refrigerant Oil Type RB68EP
Compressor Type Inverter Rotary
L.R.A A /
Compressor Rated Load Amp (RLA) A 10.82
Compressor Power Input W 1440
Compressor Thermal Protector 1NT11L-6233
Throttling Method Electron expansion valve
Cooling Operation Ambient Temperature
Range
OF -0.4~118.4
Heating Operation Ambient Temperature
Range
OF -4~75.2
Condenser Material Aluminum Fin-copper Tube
Condenser Pipe Diameter inch ĭ
Rows-Fin Gap(mm) inch 2-1/18
Coil length (l) X height (H) X coil width (L) inch 33 1/2X1 /12X26
Fan Motor Speed (rpm) (H/M/L) rpm 630
Output of Fan Motor W 60
Fan Motor RLA A 0.62
Fan Motor Capacitor ȝ) /
Air Flow Volume of Outdoor Unit CFM 1883
Fan Type-Piece $[LDOÀRZ
Fan Diameter inch ĭ
Defrosting Method Automatic Defrosting
Climate Type T1
Isolation I
Moisture Protection IPX4
Permissible Excessive Operating Pressure
for the Discharge Side MPa 4.3
Permissible Excessive Operating Pressure
for the Suction Side MPa 2.5
Dimension (W/H/D) inch 38X27 9/16X15 39/64
Dimension of Package (L/W/H) inch 40 13/32X18X29
Dimension of Package(L/W/H) inch 40 1/2X18X29 1/2
Net Weight lb 114.7
Gross Weight lb 124.6
efrigerant Charge R410A
Refrigerant Charge oz 56.45
6SHFL¿FDWLRQV

Service Manual - VFH-B 18/24 Series
6
Outdoor
Unit
Cross-sectional Area of Power Cable Conductor sq in 0.0032
Recommended Power Cable(Core) N 3
Connection Pipe Connection Method Flare Connection
Not Additional Gas Connection Pipe Length ft 32.8
Connection Pipe Gas Additional Charge oz/ft. 0.2
Outer Diameter of Liquid Pipe1 inch 1/4
Outer Diameter of Liquid Pipe2 inch 1/4
Outer Diameter of Gas Pipe1 inch 3/8
Outer Diameter of Gas Pipe2 inch 3/8
Connection Pipe Max. Height Distance(indoor and
indoor) ft 32.8
Connection Pipe Max. Height Distance(indoor and
outdoor and indoor up) ft 32.8
Connection Pipe Max. Height Distance(indoor and
outdoor and outdoor up) ft 32.8
Max. equivalent connection pipe length(outdoor to
last indoor) ft 32.8
Connection Pipe Max. Length Distance(total lenght) ft 65.6
The above data is subject to change without notice; please refer to the nameplate of the unit.

Service Manual - VFH-B 18/24 Series
7
Model A-VFH24TB-1
Product Code CB228W07800_L61437
Power
supply
Rated Voltage V~ 208/230
Rated Frequency Hz 60
Phases 1
Cooling capacity(max~min) Btu/h 24000(7500~33000)
Heating capacity(max~min) Btu/h 26000(7500~35000)
Cooling Power Input(max~min) W 1920
Heating Power Input(max~min) W 2050
Cooling Current Input A 8.35
Heating Current Input A 8.9
Rated Power Input W 4550
Rated Current A 20.19
EER (Btu/h)/W 12.5
COP (Btu/h)/W 12.7
Outdoor
Unit
Compressor Trademark ZHUHAI LANDA COMPRESSOR CO.,LTD
Compressor Model QXAS-D23zX090B
Compressor Refrigerant Oil Type RB68EP
Compressor Type Inverter Rotary
L.R.A A /
Compressor Rated Load Amp (RLA) A 15.82
Compressor Power Input W 2550
Compressor Thermal Protector 1NT11L-6233
Throttling Method Electron expansion valve
Cooling Operation Ambient Temperature Range OF -0.4~118.4
Heating Operation Ambient Temperature Range OF -4~75.2
Condenser Material Aluminum Fin-copper Tube
Condenser Pipe Diameter inch ĭ
Rows-Fin Gap(mm) inch 2-1/18
Coil length (l) X height (H) X coil width (L) inch 38 21/32X1 1/2X29 7/16
Fan Motor Speed (rpm) (H/M/L) rpm 800
Output of Fan Motor W 90
Fan Motor RLA A 0.59
Fan Motor Capacitor ȝ) /
Air Flow Volume of Outdoor Unit CFM 2354
Fan Type-Piece $[LDOÀRZ
Fan Diameter inch ĭ
Defrosting Method Automatic Defrosting
Climate Type T1
Isolation I
Moisture Protection IPX4
Permissible Excessive Operating Pressure for the
Discharge Side MPa 4.3
Permissible Excessive Operating Pressure for the
Suction Side MPa 2.5
Dimension (W/H/D) inch 38 37/64X31 7/64X17 21/64
Dimension of Package (L/W/H) inch 42 1/2X19X33
Dimension of Package(L/W/H) inch 42 43/64X19 13/64X33 43/64
Net Weight lb 153.2
Gross Weight lb 164.3
efrigerant Charge R410A
Refrigerant Charge oz 77.6

Service Manual - VFH-B 18/24 Series
8
Outdoor
Unit
Cross-sectional Area of Power Cable Conductor sq in 0.0051
Recommended Power Cable (Core) N 3
Connection Pipe Connection Method - Flare Connection
Not Additional Gas Connection Pipe Length ft 98.4
Connection Pipe Gas Additional Charge oz/ft. 0.2
Outer Diameter of Liquid Pipe1 inch 1/4
Outer Diameter of Liquid Pipe2 inch 1/4
Outer Diameter of Liquid Pipe2 inch 1/4
Outer Diameter of Gas Pipe1 inch 3/8
Outer Diameter of Gas Pipe2 inch 3/8
Outer Diameter of Gas Pipe2 inch 3/8
Connection Pipe Max. Height Distance (indoor
and indoor) ft 32.8
Connection Pipe Max. Height Distance (indoor
and outdoor and indoor up) ft 32.8
Connection Pipe Max. Height Distance (indoor
and outdoor and outdoor up) ft 32.8
Max. equivalent connection pipe length (outdoor
to last indoor) ft 65.6
Connection Pipe Max. Length Distance (total length) ft 196.8
The above data is subject to change without notice; please refer to the nameplate of the unit.

Service Manual - VFH-B 18/24 Series
9
3. Outline Dimension Diagram
35 1/8
38
27 9/16
15 39/64
13 27/64
22
14 1/2
Unit:inch
Unit:inch
A-VFH18DB-1
A-VFH24TB-1
38 37/64
35 1/8 13 27/64
17 21/64
31 7/64
22
14 1/2

Service Manual - VFH-B 18/24 Series
10
4. Refrigerant System Diagram
outdoor
indoor
D1
C1
B1
A1
filter
A heat exchanger
gas -liquid separator
inverter compressor
discharge silencer
discharge temperature
sensor
SP
4-way valve
outdoor heat exchanger
fan
high pressure switch
B heat exchanger
C heat exchanger
D heat exchanger
filter
filter
filter
filter
Note: Not available for 14K/18K
model
C2
C3
D3
D2
B3
B2
A2
A3
A1:A-unit electronic expansion valve B1:B-unit electronic expansion valve
C1:C-unit electronic expansion valve D1:D-unit electronic expansion valve
A2:A-unit gas pipe temperature sensor B2:B-unit gas pipe temperature sensor
C2:C-unit gas pipe temperature sensor D2:D-unit gas pipe temperature sensor
A3:A-unit liquid pipe temperature sensor B3:B-unit liquid pipe temperature sensor
C3:C-unit liquid pipe temperature sensor D3:D-unit liquid pipe temperature sensor
Note: Not available for 14K/18K model

Service Manual - VFH-B 18/24 Series
11
5. Electrical Part
5.1 Wiring Diagram
Symbol Symbol Color Symbol Symbol Color Symbol Name
WH White GN GREEN COMP Compressor
YE Yellow BN Brown Grounding wire
RD Red BU Blue
YEGN Yellow/Green BK Black
VT Violet OG Orange
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Ɣ,QVWUXFWLRQ
A-VFH18DB-1
63610000144
N(1)
2
3
L2
3
2
L1
N(1)
3
2
N(1)
BLOCK
TERMINAL
BLOCK
TERMINAL
N(1)
2
3
θ
θ θθ
INDOOR UNIT A
RT1
RT2
RT3 OUTTUBE
TEMP.SENSOR
OUTROOM
TEMP.SENSOR
EXHAUST
TEMP.SENSOR
4YV
COMP
M1
FAN MOTOR
EKV 5
5BK FB
YEGN G
OFAN
G
G
EH
COMPRESSOR
BAND HEATER RD
RD HEAT-C
BN
EKV WH
55FA
RDBK
RT7RT6
TEMP.SENSOR TEMP.SENSOR
RDBK
TEMP.SENSOR
LIQUID PIPE
TEMP.SENSOR
GAS PIPE
RT4 RT5
θ
BK
GY COM-INNER
BU
BN
BU
BU
BN
BU
YEGN
G
BU N1
AC-L2
N2
E(PE)
AP2
N1
AC-L1
BN
AP1:Main Board
U
V
WRD
BU
YE
BU
RD
YE
L1
L1
G
W
X1
VU
4WAY
T-SENSOR
POWER
YEGN
XT1
XTA
XTB
L1
L2
COMP.
TERMINAL
BLOCK
L1
OVC-COMP SAT
WH
WH
BLOCK
TERMINAL
TERMINAL
BLOCK
N(DC-) at AP1 is higher than 30V to
the voltage of terminal P(DC+) and
Please don't touch any terminal when
WARNING
prevent the risk of electrical shock!
N1
AC-L
N2
4-WAY VALVE
GAS PIPE LIQUID PIPE
BK
WH
VT
VT
QA YA QB YB
CONNECTOR
OVERLOAD
PROTECTOR
RD
RD
BOTTOM HEAT-B
EH
BOND HEATER
G
G
G
X2
X3 X4
X5
X6
ELECTRONIC
EXPANSION
VALVE B
VALVE A
EXPANSION
ELECTRONIC
L5
L5
L2 L3
L4
2L3L
θ
θ
TUBE-A TUBE-B
INDOOR UNIT B
WH BK
YEGN

Service Manual - VFH-B 18/24 Series
12
A-VFH24TB-1
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Service Manual - VFH-B 18/24 Series
13
1
1
2 3 4 5 6 7 8 9 10
11
12
13
14
15
16
1 Terminal of compressor
2Terminal of low-temperature
cooling temperature sensor
3Overload protection terminal
of compressor
4Temperature sensor terminal
of outdoor unit
5High pressure protection
terminal
6Low pressure protection
terminal
7 Terminal of outdoor unit
8Electric heating belt terminal
of chassis
9 Terminal of 4-way valve
10 Electric heating belt terminal
of compressor
11
Terminal of temperature
sensor wire for liquid valve
and gas valve
12 Terminal of electronic
expansion valve
13
Terminal of communication wire
for indoor unit and outdoor unit
14 Neutral wire terminal for
communication
15 Live wire terminal
16 Neutral wire terminal
5.2 PCB Printed Diagram
ƔTOP VIEW
ƔBOTTOM VIEW
A-VFH18DB-1

Service Manual - VFH-B 18/24 Series
14
1 23 4 8756 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
ƔTOP VIEW
ƔBOTTOM VIEW
A-VFH24TB-1
1 Terminal of compressor
2 Low pressure protection terminal
3 High pressure protection terminal
4 Overload protection terminal of
compressor
5 Temperature sensor terminal of
outdoor unit
6 Electric heating terminal of chassis
7 Electric heating terminal of
compressor
8 Terminal of outdoor unit
9 Terminal of 4-way valve
10 Temperature sensor for liquid valve
and gas valve for unit A
11 Temperature sensor for liquid valve
and gas valve for unit B
12 Temperature sensor for liquid valve
and gas valve for unit C
13 Temperature sensor for liquid valve
and gas valve for unit D
14 Electronic expansion valve for unit A
15 Electronic expansion valve for unit C
16 Electronic expansion valve for unit B
17 Electronic expansion valve for unit D
18 Communication wire with indoor unit
19 Neutral wire for communication
20 Live wire
21 Neutral wire
22 Reactor wire 1
23 Reactor wire 2

Service Manual - VFH-B 18/24 Series
15
6. Function and Control
1 Basic functions of the system
1.1 Cooling Mode
1.1.1 Cooling conditions and process:
If the compressor is in stop status and the unit is set to cooling operation, and one of the indoor units reaches the cooling
operation condition; the electronic expansion valve, the outdoor fan and the compressor start operation. 1.1.2 Stop in cooling
operation
1.1.2.1 Compressor stops
The compressor stops immediately, the outdoor fan stops after 1min.
1.1.2.2 If some of the indoor units reach the stop condition the compressor will not stop.
The compressor operates immediately according to the required frequency. For the indoor unit with no requirement, the
corresponding electronic expansion valve will close.
1.1.3 Cooling mode transfers to heating mode
When the unit transfers to heating mode, the 4-way valve is energized after the compressor stops for 2min. All other sequences
are the same as stopping in cooling mode.
1.1.4 4-way valve: in this mode, the 4-way valve is closed.
1.1.5 Outdoor fan control in cooling mode
The outdoor fan starts 5s before the compressor. The outdoor fan will run in high speed for 3min after starting and then it will run
in set speed. The fan shall run at every speed for at least 80s. (When the quantity of running indoor unit is changed, the unit
will enter the control described in 1.3.5.1 and 1.3.5.2);
When the compressor stops, the outdoor fan runs at present speed and stops after 1min.
1.2 Dry Mode
1.2.1 The dry conditions and process are the same as those in cooling mode;
1.2.2 The status of 4-way valve: closed;
1.2.3 The temperature setting range: 60 ~ 80°F;
1.2.4 Protection function: the same as those in cooling mode;
1.2.5 In dry mode, the maximum value A of the capacity requirement percentage of single unit is 90% of that in cooling mode. The
open condition of the electronic expansion valve, outdoor fan and compressor is the same as those in cooling mode.
1.3 Heating Mode
1.3.1 Cooling conditions and process:
When one of the indoor units reaches the heating operation condition, the unit starts heating operation.
1.3.2 Stop in heating operation:
1.3.2.1 When all the indoor units reach the stop condition, the compressor stops and the outdoor fan stops after 1min;
1.3.2.2 Some of the indoor units reach the stop condition
The compressor reduces the frequency immediately and operates according to the required frequency;
1.3.2.3 Heating mode transfers to cooling mode(dry mode), fan mode
a. The compressor stops; b. the power of 4-way valve is cut off after 2min; c. the outdoor fan stops after 1min; d. the status of
4-way valve: energized;

Service Manual - VFH-B 18/24 Series
16
1.3.3 Outdoor fan control in heating mode
The outdoor fan starts 5s before the compressor and then it will run in high speed for 40s;
The fan shall run at every speed for at least 80s;
When the compressor stops, the outdoor fan stops after 1min.
1.3.4 Defrosting function
When the defrosting condition is met, the compressor stops; the electronic expansion valve of all indoor units open in big angle;
the outdoor fan stops after 40s of the stop of compressor, meanwhile, the 4-way valve reverses the direction; after the 4-way
valve reverses the direction, the compressor starts; then begins to calculate the time of defrosting, the frequency of the
compressor rises to reach the defrosting frequency.
1.3.5 Oil-return control in heating mode
1.3.5.1 Oil-return condition
The whole unit is operating in low frequency for a long time
1.3.5.2 Oil-return process in heating mode
The indoor unit displays “H1”
1.3.5.3 Oil-return finished condition in heating mode
The duration reaches 5min
1.4 Fan Mode
The compressor, the outdoor fan and the 4-way valve are closed; temperature setting range is 6086°F.
2. Protection Function
2.1 Mode Conflict Protection of indoor unit
When the setting mode is different of different indoor unit, the unit runs in below status:
a. The mode of the first operating indoor unit is the basic mode, then compare the mode of the other indoor units to see if there
is a conflict. Cooling mode (dry mode) is in conflict with heating mode.
b. Fan mode is in conflict with heating mode and the heating mode is the basic mode. No matter which indoor unit operates first,
the unit will run in heating mode.
2.2 Overload protection function
When the discharge line temperature is a little low, the compressor raises the operation frequency; when the discharge line
temperature is a little high, the compressor frequency is restricted or slows down the operation frequency; when the discharge
line temperature is too high, the compressor protection stops running.
If the discharge temperature protection continuously appears for 6 times, the compressor can’t resume running. The
compressor can resume running after cutting off the power and then putting through the power. (if the running time of the
compressor is longer than 7min, the protection times record will be cleared)
2.3 Discharge Protection Function
When the discharge temperature is a little low, the compressor raises the operation frequency; when the discharge temperature
is a little high, the compressor frequency is restricted or slows down the operation frequency; when the discharge temperature
is too high, the compressor protection stops running.
If the discharge temperature protection continuously appears for 6 times, the compressor can’t resume running. The
compressor can resume running after cutting off the power and then putting through the power. (if the running time of the
compressor is longer than 7min, the protection times record will be cleared).

Service Manual - VFH-B 18/24 Series
17
2.4 Communication malfunction
Detection of the quantity of installed indoor units:
After 3min of energizing, if the outdoor unit does not receive the communication data of any indoor unit, the outdoor unit will
judge that indoor unit is not installed and will treat it as it is not installed. If the outdoor unit receives the communication data of
that indoor unit later, the outdoor unit will treat that unit as it is installed.
2.5 Overcurrent Protection
a. Overcurrent protection of complete unit; b. phase wire current protection; c. compressor phase current protection
2.6 Compressor high-pressure protection
2.6.1 When the high-pressure switch is detected cut off for 3s continuously, the compressor will enter high-pressure protection
and stops. Meanwhile, the outdoor unit will send the signal of “high-pressure protection” to the indoor units;
2.6.2 After the appearance of high-pressure protection, when the high-pressure switch is detected closed for 6s continuously,
the compressor can resume running only after resetting the power.
2.7 Compressor overload protection
If the compressor overload switch trips, the indoor unit will display the corresponding malfunction as it stops when the indoor
temperature reaching set temperature. When the compressor stops for more than 3min and the compressor overload
switch is reset, the unit will resume operation status automatically. If the protection occurs more than 6 times the unit cannot
resume operation status automatically, but can resume running only after cutting off the power and then putting through the
power (if the running time of the compressor is longer than 30min, the protection times record will be cleared).
2.8 Compressor Phase-lacking Protection
When the compressor starts, if one of the three phases is detected open, the compressor will enter phase-lacking protection.
The malfunction will be cleared after 1min, the unit will restart and then detect if there is still has phase-lacking protection. If the
phase-lacking protection is detected for 6 times continuously, the compressor will not restart but can resume running only after
cutting off the power and then putting through the power. If the running time of the compressor is longer than 7min, the
protection times record will be cleared.
2.9 IPM Protection
2.9.1 When the IPM module protection is detected, the unit will stop as the indoor temperature reaching set temperature, PFC is
closed, display IPM protection malfunction. After the compressor stops for 3min, the unit will resume operation status
automatically; if the IPM protection is detected for more than 6 times continuously (If the running time of the compressor is
longer than 7min, the protection times record will be cleared), the system will stop and send the signal of module protection to
indoor unit. The unit can not resume operation status automatically, but can resume running only after resetting the power.
2.9.2 IPM module overheating protection
2.9.2.1 When TIPMη85ć, prohibit to raise frequency;
2.9.2.2 When TIPM≥ 90ć, the operation frequency of compressor slows down by 15% every 90s according to the present
capacity requirement of the complete unit. It will keep 90s after slowing down the frequency. After slowing down the frequency,
if TIPM≥ 90ć, the unit will circulate the above movement until reaching the minimum frequency; if 85ćζTIPMζ90ć, the unit
will run at this frequency; when TIPM≤ 85ć, the unit will run at the frequency according to the capacity requirement;
2.9.2.3 When TIPM≥ 95ć, the compressor stops. After the compressor stops for 3min, if TIPMζ85ć, the compressor and the
outdoor fan will resume operation.

Service Manual - VFH-B 18/24 Series
18
1. Select the installation location according to the require-
ment of this manual. (See the requirements in installation
part)
2. Handle unit transportation with care; the unit should not
be carried by only one person if it is more than 44.09lb.
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VXI¿FLHQW¿[LQJEROWPXVWEHLQVWDOOHGPDNHVXUHWKH
LQVWDOODWLRQVXSSRUWLV¿UP
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5. Use equipped or appointed components during installation.
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ishing installation.
Electrical Safety Precautions:
7. Notes for Installation and Maintenance
1. Cut off the power supply toair conditioner before
serviceDQGPDLQWHQDQFH
2. The air conditioner must use an isolated circuit and
not share the same circuit with other appliances.
3. The air conditioner should be installed in a
suitable location and ensure the power is accessible.
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 during installation and maintenance.
5. Have the unit adequately grounded. The grounding wire
cannot be used for other purposes.
6. Must apply protective accessories such as protective
boards, cable-cross loopsand wire clips.
7. The live wire, neutral wire and grounding wire of power
supply must correspond to the live wire, neutral wire
and grounding wire of the air conditioner.
8. The power cord and power connection wires cannot
be SinchedE\KDUGREMHFWV
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poisonous gas; Do not lengthen the connection pipeby
welding.
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refrigerant. Never leave air in the refrigerant line as it may lead
to rupture or other hazards.
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completed.
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 to minimize the density of refrigerant.
5. Never touch the refrigerant piping or compressor without
wearing glovesto avoid scald or frostbite.
Safety Precautions:
Important!
Please read the safety precautions carefully before
installation and maintenance.
The following contents are very important for installation
and maintenance.
Please follow the instructions below.
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instructions.
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electrical codes.
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manual.
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GLVWULEXWRURUTXDOL¿HGSHUVRQ
Ɣ$OOHOHFWULFZRUNPXVWEHSHUIRUPHGE\DOLFHQVHG
technician according to local regulations and the
instructions given in this manual.
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LQFRUUHFWRSHUDWLRQWRSUHYHQWHOHFWULFVKRFNFDVXDOW\DQG
other accidents.
Warnings
Refrigerant Safety Precautions:
,PSURSHULQVWDOODWLRQPD\OHDGWR¿UHKD]DUGH[SORVLRQ
HOHFWULFVKRFNRULQMXU\
Installation Safety Precautions:
Part ė: Installation and Maintenance
10. If the power cord or connection wire is not long enough,
please get the specialized power cord or connection wire
from the manufacture or distributor. Do not extend the wire by
yourself.
11. A circuit breaker must be installed in the circuit. The
breaker should beall-pole parting and the contact parting
distance should be more than LQFK
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the valves are opened before energizing.
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SOHDVHHOLPLQDWHWKHHOHFWULFOHDNDJH
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if it is burnt; do not replace it with a copper wire or
conducting wire.
15. If the unit is to be installed in a humid place, the circuit
EUHDNHUPXVWEHLQVWDOOHG

Service Manual - VFH-B 18/24 Series
19
Main Tools for Installation and Maintenance
1. Level meter, measuring tape
4. Electroprobe
(OHFWURQLFOHDNDJHGHWHFWRU
10. Pipe pliers, pipe cutter
2. Screw driver
5. Universal meter
8. Vacuum pump
11. Pipe expander, pipe bender
3. Impact drill, drill head, electric drill
6. Torque wrench, open-end wrench, inner
hexagon spanner
9. Pressure meter
12. Soldering appliance, refrigerant container


Service Manual - VFH-B 18/24 Series
20
Preparation before installation
Prepare tools
Read the requirements
for electric connection
select installation
location
Select indoor unit
installation location
Install wall-mounting
frame, drill wall holes
Connect pipes to indoor
unit and drainage pipe
Connect wires to indoor unit
Connect wires to outdoor unit
Bind up pipes and
hang the indoor unit
Make the bound pipes pass
through the wall hole and then
connect outdoor unit
Neaten the pipes
Vacuum pumping and leakage detection
Check after installation and test operation
Finish installation
Note: this flow is only for reference; please find more detailed installation steps in this section.
Select outdoor unit
installation location
Install the support of outdoor unit
(select it according to the actual situation)
Install drainage joint of outdoor unit
(only heat pump)
Connect pipes to outdoor unit
Start installation
Set outdoor unit
Installation procedures
8. Installation Manual