MDL Solutions PFWSL-01 Manual

SK2017 AHRI PFWSL-V/P-AECM-001

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SK2017 AHRI PFWSL-V/P-AECM-001
INVESTING IN QUALITY, RELIABILITY & PERFORMANCE
ISO 9001 QUALITY
World Leading Design and Technology
Every product is manufactured to meet
the stringent requirements of the
internationally recognized ISO 9001
standard for quality assurance in design,
development and production.
Equipped with the latest air-conditioning test rooms
and manufacturing technology, we produce over
50,000 fan coil units each year, all conforming to the
highest international standards of quality and safety.
CE SAFETY STANDARDS
The Highest Standards of Manufacturing
All products conform to the Certificate
Europe directives (Machinery Safety,
Electromagnetic Compatibility and Low
Voltage), as required throughout the
European Community, to guarantee
correct standards of safety.
In order to guarantee the very highest standards and
performance, we manage every stage in the
manufacturing of our products. Throughout the
production process we maintain strict control,
starting with our extensive resources in research and
development through to the design and
manufacture of almost every individual component,
from molded plastics to the assembly of units and
controllers.
WEEE MARK
Quality Controlled from Start to Finish
All products conform to the “WEEE”
directive to guarantee correct standards
of environmental solutions.
Our highly trained staff and strict quality control
methods enable us to produce products with an
exceptional reputation for reliability and efficiency,
maintained over many years. As well as CE
certification and ISO 9001, several products ranges
have UL / ETL safety approval in the USA and Canada,
Eurovent performance and sound certification as
well as ROHS compliance for Europe, giving you the
confidence of knowing our company is the right
choice when selecting fan coil units.
ALWAYS MAKE SURE THIS MANUAL REMAINS WITH THE UNIT. READ THIS MANUAL BEFORE PERFORMING ANY
OPERATION ON THE UNIT.

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SK2017 AHRI PFWSL-V/P-AECM-001
Table of Contents
A. Technical Data....................................................................................................................................................................5
A.1. General Description.............................................................................................................................................................5
A.2. General Specification ..........................................................................................................................................................6
A.2.1. 2-Pipe Systems .............................................................................................................................................................6
A.2.2. 4-Pipe Systems .............................................................................................................................................................7
A.3. Coil Data..............................................................................................................................................................................8
A.3.1. 2-Pipe Systems .............................................................................................................................................................8
A.3.2. 4-Pipe Systems .............................................................................................................................................................8
A.4. Dimensions ..........................................................................................................................................................................9
A.5. Valve Information (Optional).............................................................................................................................................10
B. Installation.......................................................................................................................................................................12
B.1. Safety Precautions.............................................................................................................................................................12
B.2. Installation and Location...................................................................................................................................................13
B.3. Front Panel Removal..........................................................................................................................................................14
B.4. Electrical Connection .........................................................................................................................................................14
B.5. Piping Connections ............................................................................................................................................................15
B.6. Valve and External Drain Pan Installation .........................................................................................................................16
C. Maintenance....................................................................................................................................................................18
C.1. General Maintenance........................................................................................................................................................18
C.2. Regular Maintenance ........................................................................................................................................................18
C.3. Filter Installation & Cleaning .............................................................................................................................................18
C.4. Fan Motor Assembly Maintenance....................................................................................................................................19
D. Control Specifications: Complete Function PCB – S Type Control .....................................................................................20
D.1. I/O Port Definitions............................................................................................................................................................20
D.2. Wiring Diagrams ...............................................................................................................................................................21
D.2.1. Standard S Type Control PCB......................................................................................................................................21
D.2.2. Master-Slave Networking Wiring Diagram.................................................................................................................22
D.3. Configuration Settings.......................................................................................................................................................23
D.4. Control Logics for 2-Pipe System .......................................................................................................................................25
D.4.1. With Valve Configuration ...........................................................................................................................................25
D.4.2. Without Valve Configuration......................................................................................................................................27
D.5. Control Logics For 4-Pipe System.......................................................................................................................................28
D.6. Sleep Mode........................................................................................................................................................................30
D.7. Auto Fan Speed .................................................................................................................................................................30
D.8. Modulating Valve Control Under Energy Saving Mode .....................................................................................................31
D.9. Buzzer................................................................................................................................................................................31
D.10. Auto Restart ....................................................................................................................................................................31
D.11. On/Off Switch On The Front Panel ..................................................................................................................................31
D.12. Electric Heater Safety Switch...........................................................................................................................................31
D.13. LED Display and Error Description...................................................................................................................................32
D.14. LED Display on Master/Slave Connection........................................................................................................................33

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SK2017 AHRI PFWSL-V/P-AECM-001
E. Networking System ..........................................................................................................................................................34
E.1. Master-Slave Network .......................................................................................................................................................34
E.1.1. Master Unit Control Settings ......................................................................................................................................34
E.1.2. Master-Slave Network Setup......................................................................................................................................35
E.1.3. Master-Slave Communication Method.......................................................................................................................37
E.2. Open Modbus protocol......................................................................................................................................................38
F. Control Specifications: Flexible Function PCB – W Type Control........................................................................................41
F.1. Features .............................................................................................................................................................................41
F.2. I/O Port Definitions ............................................................................................................................................................41
F.3. Onboard Configuration ......................................................................................................................................................41
F.4. Wiring Diagrams ................................................................................................................................................................42
F.4.1. Standard W Type Control PCB.....................................................................................................................................42
F.4.2. Zone Control Wiring Diagram (On/Off Thermostat) ...................................................................................................43
F.5. Control Logics Specification ...............................................................................................................................................44
F.5.1. Unit Power On/Off ......................................................................................................................................................44
F.5.2. Alarm Protection and Error Display ............................................................................................................................44
F.5.3. Modulating Signal Input..............................................................................................................................................44
F.6. LED Display and Error Description......................................................................................................................................44
G. User Interface..................................................................................................................................................................45
G.1. Remote Handset for S Type Control...................................................................................................................................45
G.2. Wired Wall Pad Controller for S Type Control ...................................................................................................................46
G.3. Thermostat for W Type Control.........................................................................................................................................47
G.4. Remote handset for Thermostat in W Type Control ..........................................................................................................48
H. Sensor Resistance R-T Conversion Table ..........................................................................................................................49
I. Troubleshooting................................................................................................................................................................51
J. Accessories Descriptions...................................................................................................................................................52
J.1. Electrical Heater .................................................................................................................................................................52
J.2. Auxiliary External Drain Pan...............................................................................................................................................53
J.3. ABS Supporting Feet...........................................................................................................................................................53

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SK2017 AHRI PFWSL-V/P-AECM-001
Model Code Nomenclature
PFWSL
-
01
-
V
S
-
AECM
AECM
EC Motor Configuration
S
Complete function onboard PCB with
integrated group control functionality.
W
Flexible function onboard PCB with zone
control functionality.
P
Chilled/Hot Water, 4-Pipe
V
Chilled/Hot Water, 2-Pipe
VEH
Chilled Water, 2-Pipe with Electric Heater
01 - 05
Unit Sizes. See General Specification
section A for cooling and heating
capacities
PFWSL
Super Slim Universal Unit

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SK2017 AHRI PFWSL-V/P-AECM-001
A. Technical Data
A.1. General Description
The product represents all-in-one solution for cooling, heating and dehumidification. It achieves high energy saving levels as it
can be combined with low-temperature heat generators such as heat pump, condensing boilers and solar collectors. With its
sophisticated temperature regulator, it guarantees thermal comfort in every season. It heats and cools extremely quickly and
once the desired temperature is reached it maintains it accurately and silently.
STRUCTURE
The bearing structure is made of galvanized sheet-steel with holes for attaching the structure to the wall/ceiling. The “V” type
drain pan is used in the unit which ensure the unit can be installed vertically and horizontally. Fire resistant insulation is fitted
internally to provide both thermal and acoustic insulation.
FASCIA
The RAL9010 fascia is made of steel-sheet with electrostatic coating which is resistant to rust, corrosion, chemical agents,
solvents, aliphatic compounds and alcohols.
AIR DELIVERY GRILLE
The air delivery grill is made from ABS, which color is RAL9010.
HEAT EXCHANGER
The heat exchanger is a highly efficient coil in which copper pipes and aluminum fins are fixed by mechanical expansion. Coil
connections are provided with an anti-torsion system, hand air vent and water purge valves.
Coils are tested at the pressure of 25 bar and recommended for operating at 8 bar.
Blower and Motor
The unit incorporates only specially designed and tested EC motors, allowing the blower wheel to provide optimum
performance in airflow-efficiency and quiet operation.
AIR FILTER
The air filter is made of ABS with Nylon filter. It is easy to removing and cleaning, which can be cleaned by rinsing with water
or by gently vacuuming it.
Microprocessor controls (S type)
The PCB (printed circuit board) Modbus microprocessor controls functionality of the indoor fan motor, water valves (ON/OFF)
and electric heater (optional), to maintain room conditions at a user-defined set point. Temperature settings, fan speeds and
other control functions can be changed by either infrared handset or wired wall pad controller.
Electro-mechanical controls (W type)
It is suitable for connecting with an external 24VAC thermostat which sends H/M/L control signal to EC motor.
The PCB includes zone control application, simple error diagnostic and electric heater control (optional).

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SK2017 AHRI PFWSL-V/P-AECM-001
A.2. General Specification
2-Pipe Systems
Product range:PFWSL-Y-ECM Super Slim Universal Fan Coil with EC Motor
PFWSL-Y-V~-ECM Super Slim Universal Unit 2-pipe with EC Motor
PFWSL-[Size]-Y-V~-AECM
1
2
3
4
5
Unit Configuration
Configuration
2-pipe
Number Of Fan Blowers
1
2
Power Supply
(V/Ph/Hz)
115/1/60
Operation Control
~S: Complete function onboard PCB with integrated group control
functionality.
~W: Flexible function onboard PCB with zone control functionality.
Performance
Data
Air
Air Flow
H
CFM
118
188
271
339
381
M
94
148
216
267
291
L
58
91
146
218
251
Cooling
Cooling
Capacity
H
BTU/Hr
3310
5800
8326
10305
11977
M
2798
4709
6893
8530
9656
L
1945
3173
5118
7268
8599
Sensible
Cooling
Capacity
H
2457
4095
5903
7370
8496
M
2047
3344
4879
6074
6824
L
1399
2252
3583
5152
6039
Heating
Heating
Capacity
H
BTU/Hr
4197
6893
9998
12488
14331
M
3515
5698
8292
10271
11499
L
2388
3822
6005
8701
10168
Max. Electric Heater
Capacity @ 115V
kW
0.75
1
1.5
2
Sound
Sound Power Level
dB(A)
42/35/33
44/41/35
47/43/37
47/44/38
50/46/40
Sound Pressure Level
33/26/24
35/32/26
38/34/28
38/35/29
41/37/31
Electrical
Fan Motor
Power
H
W
12
14
24
18
24
M
8
10
15
13
15
L
5
6
9
8
9
Fan Motor Running
Current @ 115V_H
A
0.11
0.127
0.218
0.164
0.218
Hydraulic
Cooling
Water Flow
Rate
H
GPM
0.74
1.25
1.84
2.29
2.65
M
0.62
1.04
1.53
1.89
1.26
L
0.43
0.7
1.13
1.61
1.9
Cooling
Pressure
Drop
H
Ft. Hd.
1
3.3
7.8
4.5
6.7
M
0.5
2.4
5.6
3.2
4.6
L
0.3
1.2
3.4
2.4
3.8
Hot Water Flow Rate
GPM
Same As Cooling Water Flow Rate
@H/M/L
Hot Water
Pressure
Drop
H
Ft. Hd.
0.8
2.6
6.4
3.6
5.5
M
0.6
1.9
4.4
2.6
3.7
L
0.3
1
2.7
2
3
Water Content
Gallon
0.11
0.19
0.27
0.34
0.42
Construction and Packing
Data
Water
Type
Socket (Female NPT)
In
Inch
3/4
Out
Condensate Drainage
Connection
5/8
Dimensions
L
Inch
29 1/8
37
44 7/8
52 3/4
60 5/8
W
5 1/8
H
22 13/16
Net Weight
Lbs
41.9
48.5
55.1
61.7
68.3
a. Cooling mode (2-pipe):
b. Heating mode (2-pipe):
- Return air temperature: 80F DB/ 67F WB.
- Return air temperature: 70F.
- Inlet/ Outlet water temperature: 45F/ 55F.
- Inlet water temperature: 140F.
- Water flow-rate: same as cooling mode
(All dimensions are approximate within 1/16 of an inch of those indicated.)

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SK2017 AHRI PFWSL-V/P-AECM-001
4-Pipe Systems
Product range:PFWSL-Y-P~-ECM Super Slim Universal Unit 4-pipe with EC Motor
PFWSL-Y-P~-ECM Super Slim Universal Unit 4-pipe with EC Motor
PFWSL-[Size]-Y-P~-AECM
1
2
3
4
5
Unit Configuration
Configuration
4-pipe
Number Of Fan Blowers
1
2
Power Supply
(V/Ph/Hz)
115/1/60
Operation Control
~S: Complete function onboard PCB with integrated group control
functionality.
~W: Flexible function onboard PCB with zone control functionality.
Performance
Data
Air
Air Flow
H
CFM
118
188
271
339
381
M
94
148
216
267
291
L
59
91
146
218
251
Cooling
Total Cooling
Capacity
H
BTU/Hr
3351
5630
8087
10032
11635
M
2812
4675
6722
8292
9383
L
1928
3149
4913
7029
8292
Sensible Cooling
Capacity
H
2409
3992
5698
7131
8223
M
2010
3282
4743
5869
6585
L
1368
2200
3446
4948
5801
Heating
Heating Capacity
H
BTU/Hr
4504
7370
10646
13341
15389
M
3822
6176
8974
11158
12557
L
2668
4265
6654
9554
11226
Sound
Sound Power Level
dB(A)
42/35/33
44/41/35
47/43/37
47/44/38
50/46/40
Sound Pressure Level
33/26/24
35/32/26
38/34/28
38/35/29
41/37/31
Electrical
Fan Motor Power
H
W
12
14
24
18
24
M
8
10
15
13
15
L
5
6
9
8
9
Fan Motor Running
Current @115V H
A
0.21
0.24
0.42
0.31
0.42
Hydraulic
Cooling Water
Flow Rate
H
GPM
0.74
1.25
1.79
2.22
2.58
M
0.62
1.03
1.49
1.84
2.08
L
0.43
0.7
1.09
1.56
1.84
Cooling Pressure
Drop
H
Ft. Hd.
2.1
7.1
7.6
4.4
6.7
M
1.1
5.1
5.6
3.2
4.7
L
0.7
1.6
3.3
2.4
3.8
Hot Water Flow
Rate
H
GPM
0.5
0.82
1.18
1.48
1.71
M
0.42
0.69
1
1.24
1.39
L
0.3
0.47
0.74
1.06
1.24
Heating Pressure
Drop
H
Ft. Hd.
1.2
3.9
9.3
5.5
8.2
M
0.9
2.8
6.9
4
5.8
L
0.5
1.5
4.1
3
4.7
Water Content
Gallons
0.06
0.1
0.14
0.18
0.22
Construction and Packing
Data
Water Connection
Threaded Female NPT
Chilled Water
In
Inch
1/2
Out
Hot water
In
Out
Condensate Drainage
Connection
5/8
Dimensions
L
Inch
29 1/8
37
44 7/8
52 3/4
60 5/8
W
5 1/8
H
22 13/16
Net Weight
Lbs
41.9
48.5
55.1
61.7
68.3
a. Cooling mode (4-pipe)
b. Heating mode (4-pipe):
- Return air temperature: 80F DB/ 67F WB.
- Return air temperature: 68F..
- Inlet/ Outlet water temperature: 45F/ 55F.
- Inlet water temperature: 158F.
- Outlet water temperature: 140F.
(All dimensions are approximate within 1/16 of an inch of those indicated.)

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SK2017 AHRI PFWSL-V/P-AECM-001
A.3. Coil Data
2-Pipe Systems
Model
Fin height
Fin Length
Fins per
Inch
No. of
Rows
Fin width
No. of
Circuits
Tube Ø
PFWSL-01
11-13/16
11-7/8
15.0
2
1-3/4
2
3/8
PFWSL-02
19-3/4
2
PFWSL-03
27-5/8
2
PFWSL-04
35-1/2
3
PFWSL-05
43-3/8
3
4-Pipe Systems
Cooling Coil
Model
Fin height
Fin Length
Fins per
Inch
No. of
Rows
Fin width
No. of
Circuits
Tube Ø
PFWSL-01
11-9/16
11-7/8
16.5
2
1
2
1/4
PFWSL-02
19-3/4
2
PFWSL-03
27-5/8
3
PFWSL-04
35-1/2
4
PFWSL-05
43-3/8
4
Heating Coil
Model
Fin height
Fin Length
Fins per
Inch
No. of
Rows
Fin width
No. of
Circuits
Tube Ø
PFWSL-01
11-9/16
11-7/8
16.5
1
1/2
1
1/4
PFWSL-02
19-3/4
1
PFWSL-03
27-5/8
1
PFWSL-04
35-1/2
2
PFWSL-05
43-3/8
2
(All dimensions are approximate within 1/16 of an inch of those indicated.)

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SK2017 AHRI PFWSL-V/P-AECM-001
A.4. Dimensions
MODEL
PFWSL-01
PFWSL-02
PFWSL-03
PFWSL-04
PFWSL-05
L
29 1/8
37
44 7/8
52 3/4
60 5/8
H
22 13/16
22 13/16
22 13/16
22 13/16
22 13/16
W
5 1/8
5 1/8
5 1/8
5 1/8
5 1/8
(All dimensions are approximate within 1/16 of an inch of those indicated.)

Page 10 of 53
SK2017 AHRI PFWSL-V/P-AECM-001
A.5. Valve Information (Optional)
2-Way 3/4” Valve Body
Valve Code
(valve body + ON/ OFF
thermoelectric actuator)
Valve Body Dimensions (mm)
DN
A
B
C
D
SGS14HFCA-23010101
D20
(G3/4”)
2-3/16
1-7/8
7/8
2-1/2
3-Way 3/4” Valve Body
Valve Code
(valve body + ON/ OFF
thermoelectric actuator)
Valve Body Dimensions (mm)
DN
A
B
C
D
SGS14HFCA-23010102
D20
(G3/4”)
2-3/16
3-7/16
2
4-1/16
(All dimensions are approximate within 1/16 of an inch of those indicated)
0
2
4
6
8
10
12
14
16
0 0.5 1 1.5 2 2.5 3 3.5
∆P [psi]
Cv [US gpm, psi]
Differential Pressure Chart for 3/4" valve

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SK2017 AHRI PFWSL-V/P-AECM-001
2-Way 1/2" Valve Body
Valve Code
(valve body + ON/ OFF
thermoelectric actuator)
Valve Body Dimensions (mm)
DN
A
B
C
D
SGS14HFCA-23020101
D15
(G1/2”)
2-1/16
1-7/8
3/4
2-1/2
(All dimensions are approximate within 1/16 of an inch of those indicated)
0
2
4
6
8
10
12
14
16
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
∆P [psi]
Cv [US gpm, psi]
Differential Pressure Chart for 1/2" Valve

Page 12 of 53
SK2017 AHRI PFWSL-V/P-AECM-001
B. Installation
B.1. Safety Precautions
•When installing, performing maintenance or servicing Polar Air fan coil units observe the
precautions stated in this manual as well as those stated on the labels attached to the unit.
•Ensure all local and national safety codes, laws, regulations, as well as general electrical and
mechanical safety guidelines are followed for installation, maintenance and service.
•The appliance is for indoor use only.
•Ensure the correct power supply is provided.
•If the power supply cord is damaged, it must be replaced by qualified personnel.
•Installing and servicing fan coil unit should be performed by qualified service personnel only.
•This appliance is not intended for use by persons (including children) with reduced physical, sensory
or mental capabilities, or persons lacking in experience and knowledge of the appliance, unless they
have been given supervision or instruction concerning it.
•User of this appliance is responsible for his/her own safety.
•Warranty shall be voided if installation instructions and safety precaution stated in this manual are
not observed.
•The unit should only be switched off by using the ON-OFF button on the control interface.
CAUTIONS
Before any service or maintenance operations turn off the mains electrical supply.
DO NOT turn OFF the main power supply when the unit is operating. Turn off the
unit BEFORE turning off the main power

Page 13 of 53
SK2017 AHRI PFWSL-V/P-AECM-001
B.2. Installation and Location
The unit location should be established by the installation designer, services engineer or by a technically competent person
before installation. It should take into account the technical requirements as well as the relevant current laws and
regulations. The fan coil should be installed by a qualified company, also in accordance with the relevant laws and regulations
of the country of installation.
The fan coils are designed for exposed installation. All the models are designed to be floor free standing, wall mounted or
suspended from the ceiling. Installation should allow the treated air to circulate freely throughout the room and leave
sufficient space to access the unit, in order to carry out maintenance or servicing operations.
FOR FLOOR FREE STANDING
1. Open the top left and right covers to loosen the 8 screws.
2. Lift and remove the front panel.
3. Install the unit on the wall with ABS supporting feet.
4. Complete the hydraulic connection and check for leakage.
5. Complete the electrical connection as shown in the wiring
diagrams.
6. Remount the front panel, return air grille and filter.
FOR WALL-MOUNTED WITH BOTTOM RETURN
1. Open the top left and right covers to loosen the 8 screws
2. Lift and remove the front panel.
3. Keep a minimum clearance of 3-1/8” from the floor.
4. Secure the mounting brackets to the wall, then suspend the unit
by the mounting brackets, as shown in figure.
5. Complete the hydraulic connection and check for leakage.
6. Complete the electrical connection as shown in the wiring
diagrams.
7. Remount the front panel, return air grille and filter.
FOR CEILING-MOUNTED
1. Open the top left and right covers to loosen the 8 screws.
2. Lift and remove the cover.
3. Secure the mounting brackets to the ceiling, then suspend the
unit by the mounting brackets. To correctly position flanges
and brackets, see the dimensional data.
4. Complete the hydraulic connection and check for leakage.
5. Complete the electrical connection as shown in the wiring
diagrams Make electrical connection as shown in the wiring
diagrams.
6. Remount the front panel, return air grille and filter.
(All dimensions are approximate within 1/16 of an inch of those indicated)

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SK2017 AHRI PFWSL-V/P-AECM-001
B.3. Front Panel Removal
Step 1: Unlock grill and remove the filter.
Step 2: Lift the front panel and remove it.
B.4. Electrical Connection
The fan coil comes fully wired and only requires connecting to the mains electricity supply and to any room controls.
Remove the front panel, then control box is shown below.
Connect the wires according to wiring diagram.

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SK2017 AHRI PFWSL-V/P-AECM-001
B.5. Piping Connections
The fan coils have been designed and made for installation in heating and air-conditioning systems.
The characteristics of the water fittings are given below:
Main pipes connection
The position of the water fittings may be reversed from left to right during installation.
Installation diagram of water connections
1. Fan 2. Heat exchanger 3. Manual bleeds 4. Joint 5. Valve
CONDENSATE DRAINAGE
For use in air-conditioning systems, the fan coils are fitted with a condensate-collecting tray to which a drainpipe can be
connected. Connect an insulated drainage pipe (inside ø 5/8”) to the hole of the tray and direct it towards a suitable drain
Notes:
i. Check that the condensation flows out regularly into the tray.
ii. The drainage pipe should have a 2% slope towards the drain.
iii. Check all the joints for leaks.
iv. Apply heat-insulating material to the joints.

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SK2017 AHRI PFWSL-V/P-AECM-001
B.6. Valve and External Drain Pan Installation
Horizontal type
Piping for 2-Pipe System
Piping for 4-Pipe System
3-Way 4 Port Valve 3/4”
2-Way Valve 1/2” for Cooling Coil
2-Way Valve 1/2” for Heating Coil
Hot Water Outlet 1/2”
Horizontal Drain Pan
Chilled Water Outlet 1/2”
Water Outlet 3/4”
Water Inlet 3/4”
Chilled Water Inlet 1/2”
Hot Water Inlet 1/2”

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SK2017 AHRI PFWSL-V/P-AECM-001
Vertical type
Piping for 2-Pipe System
Piping for 4-Pipe System
IMPORTANT
Gravity drainage may be converted into forced drainage by attaching the condensate drain pump available as an accessory.
Chilled Water Outlet 1/2”
Chilled Water Inlet 1/2”
Hot Water Inlet 1/2”
Vertical Drain Pan
2-Way Valve 1/2” for Heating Coil
Hot Water Outlet 1/2”
2-Way valve 1/2” for Cooling Coil
Vertical Drain Pan
Water Outlet 3/4”
Water Inlet 3/4”
3-Way 4 Port Valve 3/4”

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SK2017 AHRI PFWSL-V/P-AECM-001
C. Maintenance
C.1. General Maintenance
1. Installation and maintenance should be performed by qualified personnel who are familiar with local codes and regulations,
and are experienced with this type of appliance.
2. Confirm the unit has been switched OFF before installing or service.
3. Prevent damage and unexpected shutting down of the fan coil unit.
4. Check the cleanliness of the filter and replace or clean as required monthly.
5. Clean the coils with compressed air or water to remove dust, dirt or lint. They can be brushed with a soft brush or vacuumed
with a vacuum cleaner.
6. If the water coil is not being used during the winter season, it should be drained or an anti-freezing solution should be
added to the water circuit to avoid freezing.
C.2. Regular Maintenance
1. Inspect and clean the condensate drain pan to avoid any clogging of drainage by dirt, dust, etc. Inspect drainage piping to
ensure the proper condensate flow.
2. Check and clean the coil. Clean the coils with a low-pressure water jet or low pressure air.
3. Clean and tighten all the wiring connections.
4. Drain out the water in the system and check for buildup of mineral deposits.
C.3. Filter Installation & Cleaning
1. Unlock the grille, then remove the filter.
2. Clean the filter with a brush, or with warm water.

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SK2017 AHRI PFWSL-V/P-AECM-001
C.4. Fan Motor Assembly Maintenance
Step 1: Remove the front panel.
Step 2: Loosen screws on the mounting brackets. EC motor can be removed.
Step 3: Once finished with maintenance, remount the front panel.