Polar Air SWC-V-EC-I Manual

2019-IOM-SWC-V-EC-I-001

Page 1
Table of Contents
A. Installation ........................................................................................................................................................................ 2
A.1. Safety Precautions..............................................................................................................................................................2
A.2. Before Installation .............................................................................................................................................................. 3
A.3. Mounting Plate Dimensions ...............................................................................................................................................4
A.4. Mounting Plate Installation................................................................................................................................................5
A.5. Condensate Drainage Hole Drilling .................................................................................................................................... 5
A.6. Hydronic Unit Installation................................................................................................................................................... 6
A.7. Drainage Piping Works....................................................................................................................................................... 6
A.8. Pipe Connections with Valve ..............................................................................................................................................7
B. Control Specifications ........................................................................................................................................................8
B.1. Wiring Diagram .................................................................................................................................................................. 9
B.2. Control Logic Specifications ..............................................................................................................................................10
B.3. Sleep Mode .......................................................................................................................................................................14
B.4. Auto Fan Speed................................................................................................................................................................. 14
B.5. Stepping Motor................................................................................................................................................................. 14
B.6. Buzzer ............................................................................................................................................................................... 15
B.7. Auto Restart...................................................................................................................................................................... 15
B.8. On/Off Switch ................................................................................................................................................................... 15
B.9. Electric Heater Safety Switch............................................................................................................................................15
B.10. Low Temperature Protection of Indoor Coil in Winter.................................................................................................... 15
B.11. Open Modbus Protocol ...................................................................................................................................................16
B.12. LED Display and Error Descriptions................................................................................................................................. 19
C. Master Slave Network Setup............................................................................................................................................ 20
D. User Interface.................................................................................................................................................................. 21
D.1. Remote Handset...............................................................................................................................................................21
D.2. Wall Pad ........................................................................................................................................................................... 22
E. Maintenance.................................................................................................................................................................... 25
E.1. Opening and Closing of Lift-Up Grille Cover...................................................................................................................... 25
E.2. Front Cover Assembly Removal ........................................................................................................................................ 25
E.3. Air Vent and Water Purge Valves .....................................................................................................................................25
E.4. Wiring Connections........................................................................................................................................................... 25
F. Troubleshooting Guide..................................................................................................................................................... 26
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A. Installation
A.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.
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A.2. Before Installation
Select the location for the high-wall unit with the following considerations:
1. The air inlet and outlet area should be clear without obstructions. The air should flow freely.
2. The high wall unit should be mounted on solid wall.
3. The location should allow easy access to connect water pipes easily achieve drainage.
4. Ensure the clearance around the fan coil unit conforms to the following drawing.
* Required clearance for maintenance and servicing is as shown above.
** All dimensions shown in mm.
5. The unit should be installed higher than eye level.
6. Avoid installing the unit with direct sunlight.
7. The signal receiver on the unit must be kept away from any high frequency emission source.
8. Keep the unit away from fluorescent lamps, which may affect the control system.
9. Avoid electromagnetic control system interference, ensure control wires are installed separately from
110-240 VAC power supply wires.
10. Use shielded sensor cables in where electromagnetic waves present,
11. Install a noise filter if the power supply creates any disruptive noises.
Higher than eye level.
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A.3. Mounting Plate Dimensions
SWC-12/15/18–EC-I
SWC-24–EC-I
(All dimensions shown in mm)
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A.4. Mounting Plate Installation
1. Select the structural position (e.g. a pillar or lintel) on the wall.
2. Then temporarily fasten the mounting plate on the wall with a steel nail.
3. Mount the mounting plate horizontally as shown in the
above figure or by means of gradiometer. Failed to follow
this may cause water to drip indoors and create atypical
noise.
4. Fix the mounting plate by means of expansion screws or
tapping screws.
A.5. Condensate Drainage Hole Drilling
1. Ensure that the hole for condensate drainage is correctly positioned. The height should be lower than the
bottom edge of the indoor unit.
2. Drill a 65mm diameter hole with a descending slope.
3. Seal it off with putty after installation.
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A.6. Hydronic Unit Installation
1. Pass the piping through the hole in the wall and hook the indoor unit on the mounting plate by the upper hooks.
2. Move the body of the unit from side to side to verify if it is securely fixed.
3. While pushing the unit toward the wall, lift it slightly from beneath to hook it up on the mounting plate by the lower
hooks.
4. Make sure the unit firmly rests on the hooks of the mounting plate.
A.7. Drainage Piping Works
1. Install the drain hose so that it slopes downward slightly for free drainage. Avoid installing it as shown in the below
illustrations marked with an “X”.
2. Put water in the drain pan and make sure that the water drains outdoors.
3. If the flexible drain hose provided with the indoor unit is not long enough, please extend it by joining it to an extension
hose (not provided). Be sure to insulate the connecting part of the extension drain hose with a shield pipe as shown.
4. If the attached drain hose passes through an indoor area, insulate it with heat insulation material.
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A.8. Pipe Connections with Valve
Pre-assembly
Complete Assembly
Flexible hose
Valve body with
actuator
Coil connector
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B. Control Specifications
I/O Port Definitions
Abbreviations
Ts = Setting temperature
AUX1 = Cooling water free contact
Tr = Room air temperature
AUX2 = Heating water free contact
Ti1 = Water inlet temperature
V1 = Cooling water on/off valve
Ti2 = Water outlet temperature
V2 = Heating water on/off valve
I/O
Code
2-Pipe
Analogue Input
Return air Sensor
AI1
Return air temperature (Tr)
Chilled water Sensor
AI2
Water inlet temperature sensor (Ti1)
Hot water Sensor
AI3
Water outlet temperature sensor (Ti2)
Input
IR receiver
X-DIS 1
Digital communication port to LED display/IR receiver board.
Wired wall pad
TTL1
Digital communication port to wired wall-pad board.
Digital input
Occupancy contact
ON/OFF
NO/NC contact by setting
Float switch
Float
Voltage-free (NC).
The contact is connected with float switch (NC).
Electrical heater safety
switch
EH
Voltage-free (NC).
The contact is connected with E-heater.
Power input
Phase
L
Power supply to the PCB;
Neutral
N
Power supply to the PCB;
Earth
G
Power supply to the PCB;
Voltage output
Fan 1
CN4
Fan 1 driver
Valve1
V1
On/off valve
Valve2
V2
On/off valve
Water pump
WP
Voltage output (L), Power supply to condensate pump.
Electric heater
Heat
Voltage output (L), maximum 10A.
Output
Stepping motor
CN1, CN2
Power supply to louver stepping motors.
Cooling free contact.
AUX1
Voltage free contact. Maximum load 5A.
Heating r free contact.
AUX
Voltage free contact. Maximum load 5A.
Modulating valve control
DA1
0~10Vdc for cooling water modulating valve control
Modulating valve control
DA2
0~10Vdc for heating water modulating valve control
In Modbus signal
AB
Terminals for local network serial connection
Out Modbus signal
AB
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B.1. Wiring Diagram
Louver Stepping motor
CN1
N
L
KEY
N
LV1 V2
VALVE1
HEAT
VALVE2
AUX1
AUX2
FUSE
Wired Wall
pad plug
A B A B
Yellow/Green
Reset switch SWC06~18
Legend:
L\N----Power supply
HF: 230V high speed output;
MF: 230V medium speed output;
LF: 230V low speed output;
VALVE1:230V on/off valve output;
VALVE2:230V on/off valve output;
PUMP: 230V condensate pump output (reserved)
HEAT----Electrical heater
AI1:Return air temperature sensor(Tr) ;
AI2: Water inlet temperature sensor (Ti1) ;
AI3: Water outlet temperature sensor (Ti2) ;
AUX1:Voltage free contact; ON:unit in cooling mode.
AUX2:Voltage free contact; ON:unit in heating mode.
ON/OFF:Occupancy contact
Float: Float switch contact (reserved)
CN1 2---Stepping motor
CN3---Serial BUS contacts.
CN4---Ec motor
DIS---LED receiver display
TTL---wired wall pad
TR--- 220Vac/24Vac transformer
DA1--0~10Vdc signal for cooling modulaing valve
DA2--0~10Vdc singal for heating modulating valve
CPU
AI3 AI2 AI1
CN2
prog
EH
DIS
TTL1
Reset switch for SWC-20, 24, 30
CN3
ON/OFF
TERMINAL
{
Water outlet temperature sensor
Water inlet temperature sensor
(Ti1)
Renturn sensor (Tr)
(Ti2)
iSWC-S Unit wiring scheme
EH
B A
RS485 plug
A1 A1 A2 A2
Auxiliary cooling contact
Auxiliary heating contact
Electrical heater
FUSE
DISPLAY
SCS-SWC-ECM-2019
PROs
PRO contact
110C
Plug
moter
PUMP
Reserved
GND
Float
0 10Vdc0 10Vdc
DA1
DA2
C R
TR
40VA
24Vac for modulating valve
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B.2. Control Logic Specifications
Fan Coil Unit ON/OFF
There are 3 ways to turn the system on or off:
a) By the ON/OFF button on the remote handset or wired wall pad.
b) By the programmable timer on the handset or wired wall pad.
c) By the manual control button on fan coil unit.
Auto Restart
The system uses a non-volatile memory to save the present operation parameters when the system is turned off or in case of
system failure or cessation of power supply.
The restored parameter data-set depends on the type of user interface.
a) Handset only user interface:
When the power ON signal is received by the fan coil unit and no wired wall-pad is installed, the Mode, Fan Speed, set
temperature will be the same as the handset setting before the last power OFF.
b) Wall-pad only OR wall-pad and handset user interface:
When the power ON signal is received by the fan coil unit and a wired wall-pad is installed, the Mode, Fan Speed, set
temperature and Timer ON/OFF weekly program will be the same as the wall pad setting before the last power OFF.
2-pipe Control Logic - with Modulating Valve
COOL MODE
When unit is turned on in cooling mode:
a) If Tr ≥ Ts + 1ºC (Modbus 300033 setting), MTV1 is turned on. AUX1 is closed. Fan is turned on at setting speed.
DA1 is turned on at 10VDC for 2 minutes, then check Ti1:
When Ti1≤8ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting PID
calculation. The output is the minimum output (Modbus300015 setting) ~10VDC.
When 8<Ti1≤10ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 1 PID calculation. The output is minimum output (Modbus300015 setting) ~10VDC.
When 10<Ti1≤12ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 2 PID calculation. The output is minimum output (Modbus300015 setting) ~10VDC.
When 12<Ti1≤15ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 3 PID calculation. The output is minimum output (Modbus300015 setting) ~10VDC.
When 15<Ti1≤28ºC (Modbus 300017 setting), DA1 output is kept at 10VDC.
When Ti1>28ºC (Modbus 300017 setting), DA1 output is at minimum (Modbus300016 setting). and report pre-heat alarm.
b) If Tr < Ts- 1ºC (Modbus 300033 setting), then cool operation is terminated and MTV1 and AUX1 are turned off. Indoor
fan runs at set speed. DA1 output is 0VDC.
When unit is turned off, MTV1 and AUX1 are off. DA1 is 0VDC. Fan is turned off after 30s.
The range of Ts is 16 - 30ºC.
Indoor fan speed can be adjusted to low, medium, high and auto.
LOW TEMPERATURE PROTECTION OF INDOOR COIL IN COOLING MODE
If Ti1 ≤ 2 ºC for 2 minutes, MTV1 is turned OFF. DA1 is 0VDC. Indoor fan is set at Medium speed if fan runs at low speed.
If Ti1 ≥ 5ºC for 2 minutes, MTV1 is turned ON. DA1 is set to original status. Indoor fan is changed to set speed.
FAN MODE
Indoor fan speed can be adjusted to low, medium and high. If fan speed is set to auto by Modbus, fan will run at low speed.
HEAT MODE
Without Electrical Heater (Modbus300043=0)
When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC (Modbus 300033 setting), MTV1 and AUX2 are turned on. DA1 is at 10VDC for 2 minutes, check Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), fan is turned on at low speed. DA1 is at 10VDC.
If 28ºC<Ti1< 28(Modbus 3000017 setting) + 4ºC, fan is on at original state. DA1 is at original state.
If Ti1 ≥ 28(Modbus 3000017 setting) + 4ºC, fan is on at setting speed. DA1 output is based on water temperature difference
(Ti1/Ti2) and Modbus parameter 300027 setting PID calculation. The output is minimum output (Modbus300015 setting)
~10VDC. If Ti1 sensor is damaged, fan runs at setting speed.
b) When Tr > Ts+1 ºC (Modbus 300033 setting), MTV1 and AUX2 are turned off. DA1 is at 0VDC. fan will run at lowest
speed.
When unit is turned off, MTV1 and AUX2 are turned off. DA1 is at 0VDC. Fan is turned off after 2 minutes.
With Electrical Heater as booster (Modbus300043=1)
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When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC (Modbus 300033 setting), MTV1 and AUX2 are turned on. Fan is turned on at setting speed. DA1 is
at 10VDC for 2 minutes, then check Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), EH is turned on. DA1 is at 10VDC.
If 28ºC<Ti1< 28 (Modbus 3000017 setting) +4ºC, EH is kept at original state. DA1 is at original state.
If Ti1 ≥ 28(Modbus 3000017 setting) + 4ºC, EH is turned off. DA1 output is based on water temperature difference (Ti1/Ti2)
and Modbus parameter 300027 setting PID calculation. The output is minimum output (Modbus300015 setting) ~10VDC.
If Ti1 sensor is damaged, fan will run at set speed.
b) When Tr > Ts+1 ºC (Modbus 300033 setting), MTV1 and AUX2 are turned off. EH is turned off. DA1 is at 0VDC. fan is
turned on at low speed.
When unit is turned off, MTV1 and AUX2 are turned off. DA1 is at 0VDC. Fan is turned off after 2 minutes.
With Electrical Heater as primary heat source (Modbus300043=2)
When unit is turned on in heating mode: When Ti2 ≤ 35ºC (or Ti2 is broken) and Tr ≤ Ts - 1 ºC (Modbus 300033 setting), Fan is
turned on at setting speed, EH is turned on. When Tr > Ts + 1 ºC (Modbus 300033 setting), EH is turned off. Fan is turned on
at low speed.
When unit is turned off, EH is turned off. Fan is turned off after 2 minutes.
OVER-HEAT PROTECTION OF INDOOR COIL
If Ti1 ≥ 75ºC, then MTV1, AUX2, DA1 and EH are turned off. Indoor fan remains on and runs at high speed.
If Ti1 < 70ºC, then unit keep original state.
If the indoor coil temperature sensor is damaged or not connected, the protection mode will be overridden and the unit
will work according to the pre-heat and post-heat program.
DEHUMIDIFICATION MODE
When unit is turned on in dehumidification mode:
a) AUX1 is turned on. Ts is 24 ºC.
b) If Tr ≥ 25ºC for 30S, then MTV1 will be on for 3 minutes, and then off for 4 minutes. DA1 is on at 3 times of (Modbus
300016 setting). Fan is turned on at low speed.
c) If 16ºC ≤ Tr < 25ºC for 30S, then MTV1 will be on for 3 minutes, and then off for 6 minutes. DA1 is on at double of
(Modbus 300016 setting). Fan is turned on at low speed.
d) If Tr < 16ºC for 30S, then MTV1 will be on for 3 minutes, and then off for 10 minutes. DA1 is on at (Modbus 300016
setting). Fan is turned on at low speed.
e) At the end of the above dehumidification cycle, the system will decide the next dehumidification control option.
AUTO MODE
When unit is turned on in Auto mode, fan is turned on at setting speed for 30s, then check Tr and Ts:
If Ts≥Tr+3 ºC, the unit runs in heating mode. If Tr-3 ºC<Ts<Tr+3 ºC, the unit runs in fan mode. If Ts<Tr-3 ºC, the unit runs in
cooling mode. If unit working mode is confirmed, the unit will not change the working mode. After the unit is turned off and
restart in 2 hours, working mode will be confirmed again.
PRO INPUT FUNCTION
Standard Setting when the unit is on:
If PRO input is closed for 60S, the unit is turned off.
If PRO input is opened for 60S, the unit is turned on.
Other function can be set in Modbus.
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2-pipe Control Logic –without Valve
COOL MODE
When unit is turned on in cooling mode: If Tr ≥ Ts + 1ºC (Modbus 300033 setting), AUX1 is closed. Fan is turned on at setting
speed. If Tr < Ts, then cool operation is terminated and AUX1 is turned off. Indoor fan runs at super low speed.
When unit is turned off, AUX1 is off. Fan is turned off after 30s.
The range of Ts is 16 - 30ºC.
Indoor fan speed can be adjusted to low, medium, high and auto.
LOW TEMPERATURE PROTECTION OF INDOOR COIL IN COOLING MODE
If Ti1 ≤ 2 ºC for 2 minutes, indoor fan is set at Medium speed if fan runs at low speed.
If Ti1 ≥ 5ºC for 2 minutes, indoor fan is changed to set speed.
FAN MODE
Indoor fan speed can be adjusted for low, medium and high. If fan speed is set at auto by Modbus, fan will run at low speed.
HEAT MODE
Without Electrical Heater (Modbus300043=0)
When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC (Modbus 300033 setting), AUX2 is turned on and check Ti1 in 2 minutes:
If Ti1 < 28ºC (Modbus 300017 setting), fan is turned on at low speed.
If 28ºC<Ti1< 28(Modbus 3000017 setting) + 4ºC, fan is on at original state.
If Ti1 ≥ 28(Modbus 3000017 setting) + 4ºC, fan is on at setting speed.
If Ti1 sensor is damaged, fan works at setting speed.
b) When Tr > Ts+1ºC (Modbus 300033 setting), AUX2 is turned off. Fan runs at lowest speed.
When unit is turned off, AUX2 is turned off. Fan works at setting speed. If Ti1≥38 ºC, fan is turned off after 2 minutes.
With Electrical Heater as booster (Modbus300043=1)
When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC (Modbus 300033 setting), AUX2 is turned on. Fan is turned on at setting speed, then check Ti1 in 2
minutes:
If Ti1 < 28ºC (Modbus 300017 setting), EH is turned on.
If 28ºC<Ti1< 28 (Modbus 3000017 setting) +4ºC, EH is kept at original state.
If Ti1 ≥ 28(Modbus 3000017 setting) + 4ºC, EH is turned off.
If Ti1 sensor is damaged, fan will run at set speed.
b) When Tr > Ts+1 ºC (Modbus 300033 setting), AUX2 is turned off. EH is turned off. Fan is turned on at low speed.
When unit is turned off, AUX2 is turned off. Fan is turned off after 2 minutes.
With Electrical Heater as primary heat source (Not available)
OVER-HEAT PROTECTION OF INDOOR COIL
If Ti1 ≥ 75ºC, then AUX2 is turned off. Indoor fan remains on and runs at high speed.
If Ti1 < 70ºC, then unit keep original state.
If the indoor coil temperature sensor is damaged or not connected, the protection mode will be overridden and the unit
will work according to the pre-heat and post-heat program.
DEHUMIDIFICATION MODE
When dehumidification mode is on, AUX1 is turned on and fan is turned on at low speed.
AUTO MODE (Not available)
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2-pipe Control Logic -With 6-way Modulating Valve
COOL MODE
When unit is turned on in cooling mode:
a) If Tr ≥ Ts + 1ºC (Modbus 300033 setting), MTV1 is turned on. AUX1 is closed. Fan is turned on at setting speed. DA1 is
turned on at 0VDC for 2 minutes, then check Ti1:
When Ti1≤8ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting PID
calculation. The output is 4~0VDC.
When 8<Ti1≤10ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 1 PID calculation. The output is 4~0VDC.
When 10<Ti1≤12ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 2 PID calculation. The output is 4~0VDC.
When 12<Ti1≤15ºC, DA1 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 3 PID calculation. The output is 4~0VDC.
When 15<Ti1≤28ºC (Modbus 300017 setting), DA1 output is kept at 0VDC.
When Ti1>28ºC (Modbus 300017 setting), DA1 output is 4VDC. and report pre-heat alarm.
b) If Tr < Ts-1ºC (Modbus 300033 setting), then cool operation is terminated and MTV1 and AUX1 are turned off. Indoor fan
runs at set speed. DA1 output is 5VDC.
When unit is turned off, MTV1 and AUX1 are off. DA1 is 5VDC. Fan is turned off after 30s.
The range of Ts is 16 - 30ºC
Indoor fan speed can be adjusted to low, medium, high and auto.
LOW TEMPERATURE PROTECTION OF INDOOR COIL IN COOLING MODE
If Ti1 ≦2 ºC for 2 minutes, MTV1 is turned OFF. DA1 is set to 5Vdc. Indoor fan is turned on at Medium speed if fan runs at low
speed. If Ti1 ≧5ºC for 2 minutes, MTV1 is turned ON. DA1 is set to original status. Indoor fan is changed to set speed.
FAN MODE
Indoor fan speed can be adjusted for low, medium and high. If fan speed is set auto by Modbus, fan runs at low speed.
HEAT MODE
Without Electrical Heater(Modbus300043=0)
When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC(Modbus 300033 setting) , MTV2 and AUX2 are turned on. DA1 is at 10VDC for 2 minutes, then check
Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), fan is turned on at low speed. DA1 is at 10VDC.
If 28ºC<Ti1< 28(Modbus 3000017 setting)+4ºC, fan is on at original state. DA1 is at original state.
If Ti1 ≥ 28(Modbus 3000017 setting)+4ºC , fan is on at setting speed. DA1 output is based on water temperature difference
(Ti1/Ti2) and Modbus parameter 300027 setting PID calculation. The output is 6~10VDC.
If Ti1 sensor is damaged, fan is worked at setting speed.
b) When Tr > Ts- 1ºC (Modbus 300033 setting) , MTV1 and AUX2 are turned off. DA1 is at 5VDC. fan is turned on at lowest
speed.
When unit is turned off, MTV1 and AUX2 are turned off. DA1 is at 5VDC. Fan is turned off after 2 minutes.
With Electrical Heater as booster (Modbus300043=1)
When unit is turned on in heating mode:
a) When Tr ≤ Ts - 1 ºC(Modbus 300033 setting) , MTV2 and AUX2 are turned on. Fan is turned on at setting speed. DA1 is
at 10VDC for 2 minutes, then check Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), EH is turned on. DA1 is at 10VDC.
If 28ºC<Ti1< 28(Modbus 3000017 setting)+4ºC, EH is kept at original state. DA1 is at original state.
If Ti1 ≥ 28(Modbus 3000017 setting)+4ºC , EH is turned off. DA1 output is based on water temperature difference (Ti1/Ti2)
and Modbus parameter 300027 setting PID calculation. The output is 6~10VDC.
If Ti1 sensor is damaged, fan is worked at setting speed.
b) When Tr > Ts -1ºC (Modbus 300033 setting) , MTV2 and AUX2 are turned off. EH is turned off. DA1 is at 5VDC. fan is
turned on at low speed.
When unit is turned off, MTV2 and AUX2 are turned off. DA1 is at 5VDC. Fan is turned off after 2 minutes.
OVER-HEAT PROTECTION OF INDOOR COIL
If Ti1 ≥ 75ºC, then MTV1, AUX2, DA1 and EH are turned off. Indoor fan remains on and runs at high speed.
If Ti1 < 70ºC, then unit keep original state.
If the indoor coil temperature sensor is damaged or not connected, then the protection mode will be overridden and the
unit will work according to the pre-heat and post-heat program.
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DEHUMIDIFICATION MODE
When unit is turned on in dehumidification mode:
AUX1 is turned on. Ts is 24 ºC. If Tr ≥ 25ºC for 30S, then MTV1 will be ON for 3 minutes, then OFF for 4 minutes. DA1 is
2VDC. Fan is turned on at low speed. If 16ºC ≤ Tr < 25ºC for 30S, then MTV1 will be ON for 3 minutes, and then OFF for 6
minutes. DA1 is 2.5VDC. Fan is turned on at low speed. If Tr < 16ºC for 30S, then MTV1 will be ON for 3 minutes, and then
OFF for 10 minutes. DA1 is 3.5VDC. At the end of dehumidification cycle, the system will decide the next dehumidification
cycle.
AUTO MODE
When unit is turned on in Auto mode, fan is turned on at setting speed for 30S, then check Tr and Ts.
If Ts≥Tr+3 ºC, the unit is worked in heating mode. If Tr-3 ºC<Ts<Tr+3 ºC, the unit is worked in fan mode. If Ts<Tr-3 ºC, the unit
is worked in cooling mode.
If unit works in heating or fan mode, when Tr-Ts>3.0ºC, MTV2, MTV1 and DA1 are off for more than 10minutes. EH is off for
more than 10 minutes, the unit will work in cooling mode. If unit works in cooling or fan mode, when Ts-Tr>3.0ºC, MTV2,
MTV1 and DA1 are off for more than 10minutes. the unit will work in heating mode.
PRO INPUT FUNCTION
Standard Setting when the unit is on:
If PRO input is closed for 60S, the unit is turned off.
If PRO input is opened for 60S, the unit is turned on.
Other function can be set in Modbus.
B.3. Sleep Mode
a) The sleep mode can only be set when the unit is in cool mode or heat mode.
b) If the sleep mode is activated in cool mode, the indoor fan runs at auto speed and Ts will increase by
0.5ºC for every 30 minutes. The Maximum increasing temperature is 3ºC. If the sleep mode is activated
in heat mode, the indoor fan runs at auto speed and Ts will decrease by 0.5ºC for every 30 minutes.
c) If sleep mode is turned off, setting temperature goes back and fan is changed to set speed.
B.4. Auto Fan Speed
Cooling Mode: Fan speed cannot change until it has run for more than 30 seconds.
Heat Mode: Fan speed cannot change until it has run for more than 30 seconds.
B.5. Stepping Motor
For remote handset
Whenever the indoor fan is running, the louver can swing or stop at the desired position.
Louver angle: 0~100º, opens clockwise with widest angle at 100º.
Swing angle: 35~100º, opens clockwise to 68º. Below are the 4 fixed positions which can be set from
wireless handset.
Position
Angle
1
35º
2
57º
3
83º
4
100º
For wired wall pad
Louver angle: 0~100º, opens clockwise, with widest angle at 100º.
Swing angle: 35~100º, opens clockwise to 68º. User may stop louver at any desired position between
35~100º.
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B.6. Buzzer
The unit will beep once when it receives 1 signal.
B.7. Auto Restart
The system uses non-volatile memory to save the present operation parameters when system is turned
off or in case of system failure or cessation of power supply. Operation parameters are mode, set
temperature, louver’s position, and the fan speed. When power supply resumes or the system is
switched on again, the same operations as previously set will function.
B.8. On/Off Switch
a) This is a TACT switch to select Cool→Heat→Off operation mode.
b) In COOL mode, the set temperature of the system is 24ºC with auto fan speed. There are no timer and
sleep modes.
c) In HEAT mode, the set temperature of the system is 24ºC with auto fan speed. There are no timer and
sleep modes.
d) Master unit that does not use a wall pad will globally broadcast.
Note: When button pressing is effective, the master unit buzzer will beep twice and the slave unit will
beep once.
B.9. Electric Heater Safety Switch
•Before the electrical heater is turned on, the EH safety switch must be closed and EH is opened for 3
minutes and EC motor RPM must be more than Modbus 300020 setting.
•When electrical heater is ON, electrical heater safety switch is opened for ≥ 1 second or EC motor
RPM is lower than Modbus 300020 setting, EH will be turned off immediately and report an error
and fan speed is changed to high speed.
•Once the contact is returned to the closed ≥ 180 seconds and EC motor RPM is more than 300020
setting, reset the error and the heater will start again.
•When the EH safety switch is opened ≥ 3 times within 60 minutes the heater is not allowed to start
anymore.
•Turn off the unit to reset the fault, provided that the switch has returned to the closed position.
B.10. Low Temperature Protection of Indoor Coil in Winter
This is frost protection when the unit is off to prevent water from freezing in the coil.
If a 2-pipe system is in Standby Mode, when Tr ≦2 ºC for 2 minutes, MTV1 is turned on. AUX2 is on. DA1
is 5VDC. If Ti1 < 5ºC for 2 minutes, EH (if present) is switched on. Indoor fan is turned on at low speed. If
Tr ≧5ºC for 2 minutes, MTV2 is turned off. AUX2 is off. DA1 is 0VDC. Electric Heater is turned off. Indoor
fan is switched off.
If a 4-pipe system (or 2-pipe unit with 6-way valve) is in Standby Mode, when Tr ≦2 ºC for 2 minutes,
MTV2 is turned on. AUX2 is on. DA2 is 5VDC. (DA1 is 8VDC if using 6-way valve) If Ti1 < 5ºC for 2 minutes
EH (if present) is switched on. Indoor fan is turned on at low speed. If Tr ≧5ºC for 2 minutes, MTV2 is
turned off. AUX2 is off. DA2 is 0VDC. (DA1 is 5VDC if using 6-way valve) Electric Heater is turned off. Indoor
fan is switched off.
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B.11. Open Modbus Protocol
Transfer Mode: RTU BAUD Rate:9600bps, 8 data bits, 1 stop bit, None parity bit
The communications require a delay between reading an answer and sending the next command of 80 ms. All temperature is equal to reading data*10
accuracy: 0.1 degree C.
Supported Functions
Function Code
Function description
01(01H)
Read Coils
02(02H)
Read Discrete Inputs
03(03H)
Read Holding Registers
04(04H)
Read Input Registers
05(05H)
Write Single Coil
06(06H)
Write Single Register
15(0FH)
Write Multiple Coils
16(10H)
Write Multiple Registers
255(FFH)
Extended Commands which is used to test.
Valid Error code table:
Error code
description
definition
01 (01H)
Invalid commands
Received commands beyond valid commands
02 (02H)
Invalid data address
Data addresses beyond valid data address
03 (03H)
Invalid data
Data beyond definition range
04 (04H)
Write data not succeed
Write data not succeed
Coils table:
Description
Address
Type*
Remark
ON/OFF
100000
R/W
Sleeping mode
100001
R/W
Louver swings
100002
R/W
Energy Saving Mode
100003
R/W
PRO function
100004
R/W
Discrete table:
Description
Address
Type*
Remark
MTV1
200000
R
MTV2
200001
R
AUX1
200002
R
AUX2
200003
R
Condensate pump
200004
R
Electrical heater
200005
R
Wired wall pad
200006
R
PR-O1
200007
R
Float switch
200008
R
Reserved
200009
R
EH safety switch
200010
R
Internal test
200011
R
Testing purpose only.
Holding Register table:
Description
Address
Type*
Remark
Mode setting
300000
R/W
Cooling mode = 01(H), Humidify mode = 02(H), Fan mode = 04(H),
Heating mode = 08(H), Auto mode = 10(H)
Fan speed setting
300001
R/W
Low speed = 04(H), Medium speed = 02(H), High speed = 01(H)
Auto fan speed = 07(H)
Louver swing setting
300002
R/W
Position1=01(H), Position2=02(H), Position3=03(H),
Position4=04(H), Auto=0F(H), Stop=00(H)
Setting temperature
300003
R/W
16~30 (actual*10 format)
Address setting
300004
R/W
1~255
Reset
300005
W
=0x33 reset error
Reserved
300006
W
Reserved
300007
W
Reserved
300008
W
Reserved
300009
W
Hours in Timer on
300010
R/W
Timer ON
Minute in Timer on
300011
R/W
Timer ON
Hours in Timer off
300012
R/W
Timer OFF
Minute in Timer off
300013
R/W
Timer OFF
Icon of Timer ON or OFF
300014
R/W
BIT0 = Icon of Timer ON, BIT1 = Icon of Timer OFF,
1 = enable, 0 = disable
Minimum output DA1
300015
R/W
Default 25% (2.5vdc)
Minimum output DA2
300016
R/W
Default 25% (2.5vdc)
Pre-heat temperature setting
300017
R/W
25~35, default: 30
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Reserved
300018
R/W
Default: 40% (4VDC) or (10.4mA)
Super low speed rpm
300019
R/W
0~10V, default:2VDC
Low speed rpm
300020
R/W
1~10VDC, default: 3VDC
Medium speed rpm
300021
R/W
1~10VDC, default: 6VDC
High speed rpm
300022
R/W
1~10VDC, default: 8.5VDC
Signal output setting
300023
R/W
1~10VDC (used to test,0 = disable)
Temperature sampling time
300024
R/W
2~100, default: 5S
Factor of auto fan speed
300025
R/W
2~150, default:20
Factor of modulating valve
300026
R/W
2~250, default:150
Ti1 and Ti2 difference setting
300027
R/W
3~15, default:5
Reserved
300028
R/W
3~15, default:10
Controller Hardware type setting
300029
R/W
0=air cleaner (S5)
1=FCU (S1/S2/S3, SWC-S) (Default)
2=AHU (S6) or (AHU+W5)
3=AHU+AQI (S5+S6)
4=Zone controller(S7)
Degree unit setting
300030
R/W
0=degree C
1=degree F
Temperature display setting
300031
R/W
0=Room temperature display on LED
1=Setting temperature display on LED
Setting temperature range
300032
R/W
0=setting temperature range is from 16~30
1=Setting temperature range is fixed. Cooling=24oC Heating=21oC
Temperature band setting
300033
R/W
1~9, default:1
Reserved
300034
R/W
30~200, default:60
Reserved
300035
R/W
10~80, default:50
Reserved
300036
R/W
460~1200, default:800
Reserved
300037
R/W
100~500, default:200
Reserved
300038
R/W
30~70, default:50
Reserved
300039
R/W
10~30, default:10
Reserved
300040
R/W
100~1000, default:500
Reserved
300041
R/W
500~9000, default: 2000
Reserved
300042
R/W
500~9000, default: 2000
Reserved
300043
W
1
Reserved
300044
W
1
Reserved
300045
W
1
Software type
300046
R/W
0=2-pipe+MTV
1=2-pipe without valve
2=4-pipe+std valve
3=4-pipe+6-way valve
EH type
300047
R/W
0=without EH, 1=EH as booster; 2=EH as primary
DA1 control signal
300048
R/W
0=Tr/Ts, 1=ESP
EC motor input ports
3000049
R/W
0=CN4 working (Default)
1=CN5 working
2=CN4+CN5 working
PRO1 input type
300050
R/W
0=N, 1=NC
Tr sensor setting
300051
R/W
0=sensor on the wired wall pad (Default)
1=sensor on the main PCB
Reserved
300052
R/W
0~120, default: 80
Optimized swing angle
300053
R/W
200~999 default:0;
E-heater
300054
R/W
Unit: KW*10
Room temp. factor
300055
R/W
90~120, default:103
Water inlet temp. factor
300056
R/W
90~120, default:103
Delta T factor
300057
R/W
90~120, default:102
Product type
300058
R/W
00~99; default:00
Product model
300059
R/W
000~999; default:000
Ex-works data
300060
R/W
0000~9999
Software version
300061
R
10~99 default:10
Hardware version
300062
R
10~99 default:10
Reserved
300063
R/W
200rpm~1500rpm default:500
Reserved
300064
R/W
200rpm~1500rpm default:1200
Reserved
300065
R/W
200rpm~1500rpm default:500
Reserved
300066
R/W
200rpm~1500rpm default:1200
Reserved
300067
R/W
0=EC motor1 working
1=EC motor2 working
2=EC motor 1/2 working default:2
In auto mode, temp. Band setting
300068
R/W
1~15, default: 3
Reserved
300069
R/W
Reserved
300070
R/W
Unit power input at High speed
300071
R/W
W*10
Unit power input at Med. speed
300072
R/W
W*10
Unit power input at Low speed
300073
R/W
W*10
Unit heat capacity at High speed
300074
R/W
KW*10
Unit heat capacity at Med. speed
300075
R/W
KW*10
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Unit heat capacity at Low speed
300076
R/W
KW*10
Unit cool capacity at High speed
300077
R/W
KW*10
Unit cool capacity at Med. speed
300078
R/W
KW*10
Unit cool capacity at Low speed
300079
R/W
KW*10
Input Register table:
Description
Address
Type*
Remark
Tr temperature sensor
400000
R
Ti1 temperature sensor
400001
R
Ti2 temperature sensor
400002
R
Reserved
400003
R
Reserved
400004
R
Error code
400005
R
Bit0 = Room temperature sensor error
Bit1 = Ti1 temperature sensor error
Bit2 = Ti2 temperature sensor error
Bit3 = Float switch error
Bit4 = Indoor coil low temperature protection
Bit5 = Indoor coil over heat protection
Bit6 =Filter switch
Bit7 = Electrical heater failure
Bit8 = Motor1 Error
Bit9 =Motor2 Error
Bit10 = System parameters error
Bit11 = Anti-frozen error
Bit12 = Ti3 temperature sensor error
Bit13 = Ti4 temperature sensor error
Bit14 =PM2.5 sensor
Bit15 =AQI Error
Fan speed status
400006
R
Low = 04(H) Medium = 02(H) High = 01(H)
Reserved
400007
R
Reserved
400008
R
EH
400009
R
0= disable, 1=booster, 2=primary
Unit type
400010
R
DA1
400011
R
DA2
400012
R
Reserved
400013
R
Reserved
400014
R
Reserved
400015
R
Reserved
400016
R
Unit status
400017
R
Cooling mode = 01(H) Humidify mode = 02(H)
Fan mode = 04(H) Heating mode = 08(H)
Unit OFF=32(H)
Temperature in wall pad
400018
R
Motor running time
400019
R
Motor running terms
400020
R
0~100,
Cooling capacity
400021
R
Cooling capacity terms
400022
R
0~100,
Heating capacity
400023
R
Heat capacity terms
400024
R
0~100,
Reserved
400025
R
Reserved
400026
R
EC motor1 actual RPM
400036
R
EC motor2 actual RPM
400037
R
EC motor1 error
400038
R
EC motor2 error
400039
R
* R = read only, W = write only, R/W = read and write.
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B.12. LED Display and Error Descriptions
Power / Operation LED light (both green)
Unit on
Power LED Off, Operation LED On
Unit in standby
Power LED On, Operation LED Off
For all units - Green LED
Error Description
Blink
LED display
Reason
Remedy
Return air sensor
failure
Green LED blinks 1
times, stops for 3s
E1
Room sensor
unplugged or
damaged.
1. Check if Tr plug is connected or not.
2. Check if sensor’s resistance is correct
or not.
Indoor coil sensor 1
failure
Green LED blinks 2
times, stops for 3s
E2
Ti1 sensor
unplugged or
damaged.
1. Check if Ti1 plug is connected or not.
2. Check if sensor’s resistance is correct
or not.
Indoor coil sensor 2
failure
Green LED blinks 3
times, stops for 3s
E3
Ti2 sensor
unplugged or
damaged.
1. Check if Ti2 plug is connected or not.
2. Check if sensor’s resistance is correct
or not.
Water pump failure
Green LED blinks 4
times, stops for 3s
E4
Float switch is
opened.
1. Check if the condensate water pipe is
connected or not.
2. Check if the pump is functioning or
not.
Indoor coil low
temperature
protection
Green LED blinks 5
times, stops for 3s
E5
Water temperature
is lower than 3 ºC.
Check the water temperature.
Indoor coil over heat
protection
Green LED blinks 6
times, stops for 3s
E6
Water temperature
is higher than 70 ºC.
Check the water temperature
Filter Switch (S6
PCB)
Green LED blinks 7
times, stops for 3s
E7
Filter switch is
opened.
1. Check if filter block or not
2. replace teh new filter
Electric Heater
failure
Green LED blinks 8
times, stops for 3s
E8
Only for unit with
EH.
1. Change fan speed to high.
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