PolarHeat SHCW814G User manual

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Single/Dual System SHCW814G
Controller of Air Source Heat
Pump Water Heater
Installation Manual
Before installing the controller, please read the instructions in detail.

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【Safety precautions】
Symbol
description
Danger
When used incorrectly, it may cause dangerous situations,
personal injury or casualties.
Cautio
n
！
When used incorrectly, it may cause dangerous situations,
which may lead to equipment damage or accelerated damage.
Installation
Please install it on the non-combustible plate such as metal, and fix
it firmly to avoid falling due to vibration.
！
Please eliminate static electricity before installation. Live
installation and damage to components are prohibited.
The main board should not be exposed to direct sunlight, rainwater
and complex magnetic interference environment.
Do not expose to corrosive or contaminated gases, such as
sulphide gases and salt spray.
Make sure that the temperature of the electric box is between - 20
~50℃, and add exhaust fan if necessary.
Wiring
Make sure that the power input is in the OFF state.
The electrical staff should connect the wires following safety
instructions.
The input terminal is passive switching signal. Do not connect to
the power supply.
Attention should be paid to lightning protection. Make sure that
the water tank and the machine are well grounded during roof
installation.
！
Please observe the principle of isolating strong and weak signals.
Use wires that meet the required specifications.
Please use parallel grounding mode. The thickness of the
grounding wire should meet the requirements.
When connecting terminals or inserts, please tighten them to
prevent gap arcing and device damage.
Parameter
Settings
！
Set relevant parameters according to machine configuration to
ensure the normal operation of the machine.
Set relevant jumper/decoder switch according to machine
configuration to ensure the normal operation of the machine.
Operation
Input the power supply after confirming that the wiring is correct.
Ensure that environmental conditions and power supply voltage are
within permissible conditions before starting operation.

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When the machine is running, do not check the signal.
When the machine is running, do not change the parameter
settings at will.
When the machine is running, do not get too close to the machine.
Maintenance
& inspection
！
If a repair job is necessary, please contact the equipment
manufacturer. Do not repair by yourself.
Do not pull or twist power cord, communication line or probe line to
avoid serious malfunction.
Do not touch the main board components directly with your hands,
so as to avoid conducting static electricity to damage the
components.
The display screen of the wire controller is made of glass.
Attention should be paid to the protection to avoid breakage and
damage.
Others
In the desktop simulation debugging motherboard, there is the risk
of electric shock and injury, pay attention to safe operation.
If the wire controller is a touch screen, please touch it with your
finger. Do not press it or hit it with a hard object.

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1. Product Introduction
1.1 Overview
⚫This product is suitable for single compressor and double compressor system. Single-phase 220V or three-phase
380V is optional.
⚫The operation modes of the product are: hot water mode; heating / cooling mode; modular machine (8 modules).
⚫This product has the functions of power-off memory, timing on/off, forced defrosting, anti-freezing protection,
three-phase protection, current overload protection and so on.
⚫Through RS485 communication, the product can be jointly controlled by remote equipment.
1.2【Technical Specifications】
！
Operation
Voltage
AC220V±10%，50Hz±1Hz。
Display
Range
-30℃～90℃
Control
Accuracy
±1℃@25℃
Working
Environment
-25℃~70℃,≤85%RH
Storage
Environment
-30℃~85℃,≤85%RH
Switch
Output
Single Compressor
Normal Temp Type：8 way relay
Low Temp Type：10 way relay
Single relay load < 200W (current 1A) (inductive load);
Total load of relay at the same common terminal ≤1kW
(current ≈5A)
Double Compressor
Normal Temp Type：9 way relay
Low Temp Type：11 way relay
Switch Input
Single compressor
Normal Temp Type ：8 passive
digital inputs
Low Temp：8 passive digital inputs
Do not connect to power supply, external load resistance ≤
2K Ω
Double compressors
Normal Temp Type：10 passive
digital inputs
Low Temp Type：10 passive digital
inputs
Electronic
Expansion
Valve
Single compressor
Normal Temp Type：1 Electronic
Expansion Valve
Low Temp Type ：2 Electronic
Expansion Valve
12V power supply, load coil current ≤0.4A
Double compressors
Normal Temp Type：2 Electronic

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Expansion Valve
Low Temp Type ：4 Electronic
Expansion Valve
Analog input
Single compressor
Normal Temp Type：8 NTC Temp
Sensor
Low Temp Type：8 NTC Temp
Sensor
Discharge gas temperature sensor 50K 3950，Others 5K 3470
Double compressors
Normal Temp Type：12 NTC Temp
Sensor
Low Temp Type ：8 NTC Temp
Sensor
Single Compressor ：1 current
detection interface
Double Compressors ：2 current
detection interface
1.3【Spare Parts List】
Sequence
No.
Name
Model No.
Pcs
Description
1
PCB
SHXK814G1
1
Low Temp Single Compressor System
2
PCB
SHXK814G2
1
Low Temp Double Compressor System
3
PCB
SHCW814G1
1
Normal Temp Single Compressor System
4
PCB
SHCW814G2
1
Normal Temp Double Compressor System
5
Display
SHXK814
1
Touch Screen, 12V DC
6
Commu
nication
Line
4 core 7M
1
Communication line connecting PCB and touch screen
7
Transfor
mer
DB48-105-08100
1
8
Temp
sensor
2core 5K 3470
Configuration as required
9
Current
Transfor
mer
SH-D-C-A
1\2
1 for single compressor 2 for double compressor
system
Optional
1
GPRS
Module

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2. Wire Controller Display Description, Parameter Query and
Fault Table
2.1 Wire Controller Display Description(model：SHXK814)
After the first power-on, the LCD screen displays the version number of the line controller for 2 seconds, and then the
full screen displays, and it enters the normal working state.
【ON/OFF】
In the boot state, press this key to enter the shutdown state, displaying water temperature, timing state and clock,
etc.
In the shutdown state, press this key to enter the boot state, displaying the operation mode, setting temperature,
water temperature, unit, timing state and clock, etc.
After the first power-on, if there is no key-press operation for more than 60 seconds, the controller automatically
enters the state of key-lock, and the“ ” symbol is displayed. Press this key for 3 seconds to release the lock key
status and the “ ”symbol disappears.
When setting clock, timing, parameter query and parameter setting, press this key to exit the setting state.
【+】【-】
This key can be used for parameter query, parameter setting, clock adjustment, timing adjustment and
temperature setting.
Press 【+】to increase the temperature setting value and press 【-】to decrease the temperature setting value.
【Query/Time】
Press this key to enter the clock setting state. The "HOUR" of the clock flickers. Adjust the "HOUR" by pressing 【+】
【-】. Press 【Query/Time】again to enter the "MINUTE" setting, the "MINUTE" of the clock flickers. Adjust the
"MINUTE" by pressing【+】【 -】, and then press【Query/Time】to confirm the clock setting and exit the clock setting.
Press this key to cancel the timed turn-on/turn-off in the setting state.
In the state of parameter query, pressing this key can clear the unrecoverable fault.

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Press 【Query/Time】for 3 seconds and enter the parameter query state.
[timing / confirm] key
Press this key to enter the timing on / off setting.
In the non clock setting state, press this key to enter the timing period selection of the unit. There are 3 periods in
total. Press 【+】【-】keys to select the period, press this key to confirm the period. Press【+】【-】keys to select
timing on or timing off, and then press this key to confirm. At this time, the hour digit will flash, and press【+】【 -】keys
to adjust the hour time, then press this key to confirm the set hour digit. Then the minute digit will flash, press 【+】【 -】
keys to adjust the minute time, then press the this key to confirm the set minute digit and exit the timing setting state.
Cancel timer
In the timing period selection, press 【+】【 -】keys to select the period to be cancelled, and then press "time" key
to cancel the timing on and timing off settings of this period.
Forced defrost
When the system starts up and enters the unit parameter query state, press and hold the [query / time] and [timing /
confirmation] keys for more than 5 seconds, and the buzzer drips once.
A. when the system enters defrost mode, the LCD screen will display [defrosting];
B. when the exit conditions are met, the system will exit defrost automatically.
C. operating conditions: hot water mode or heating mode.
【mode】key
In "hot water" or "heating" mode, press and hold this key for 3 seconds to turn on or cancel forced electric heating;
Heating/Cooling models: in the startup state, press the [mode] key to switch the operation mode between "cooling"
and "heating" modes;
General parameter query
Query parameter method: press and hold the [query / time] key for 3 seconds to enter the parameter query status.
Display add 1 (add: for unit address, 1: for unit 1). Press the 【+】【-】key to select the unit number to query. For
example, when "add 1" is displayed, press the [mode] key to enter the parameter query of unit 1. At this time, D01 is
displayed. Press 【+】【-】key to change the parameter query item. Other unit queries are the same.
Exit -- press the "on / off" key or no operation key for more than 120 seconds to exit the parameter query.
2.2General Parameter Query Table 1
Code
Representation
Remarks
Add
Unit Address
Add 1 represents unit 1, press 【+】and 【-】to select the unit address, and press
[mode] to confirm.
d01
Non Recoverable Error Code
d02
Recoverable Error Code
d03
Tank water temperature
d04
Inlet water temperature
d05
Outlet water temperature
d06
Ambient temperature
d07
Evaporator coil temp 1
d08
Suction temp 1
d09
Discharge gas temp 1
d10
After valve temp 1 in cooling
/Return Water Temp
After valve temp in cooling and Return water temp in hot water mode
d11
Evaporator coil temp 2
d12
Suction temp 2

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d13
Discharge gas temp 2
d14
After valve temp 2 in cooling
/Return Water Temp
d15
Compressor current 1
d16
Compressor current 2
d17
Compressor Current Set Value
d18
Main Circuit EEV opening 1
d19
Main Circuit EEV opening 2
d20
Auxiliary Circuit EEV opening 1
d21
Auxiliary Circuit EEV opening 2
d22
External Version 1
d23
External Version 2
d24
Low Water Level Sensitivity
Valid in Hot Water Mode, not valid in heating/cooling Mode
d25
Medium Water Level Sensitivity
Valid in Hot Water Mode, not valid in heating/cooling Mode
d26
High Water Level Sensitivity
Valid in Hot Water Mode, not valid in heating/cooling Mode
d27
Protection Switch Status 1
d28
Protection Switch Status 2
d29
Output 1 Status
d30
Output 2 Status
d31
Output 3 Status
d32
External machine model code
d33
Communication status 1
A digital jump indicates normal communication
d34
Communication status 2
A digital jump indicates normal communication
d35
Weeks of Limited Use
d36
Historical Fault 1（Latest）
d37
Historical Fault 2
d38
Historical Fault 3
d39
Historical Fault 4
d40
Historical Fault 5
d41
Historical Fault 6（Oldest）
d42
Evaporator coil temp 3
Reserved
d43
Evaporator coil temp 4
Reserved
d44
Suction Temp 3
Reserved
d45
Suction Temp 4
Reserved
d46
After Valve temp 3
Valid in Heating/Cooling Mode，Reserved
d47
After Valve temp 4
Valid in Heating/Cooling Mode，Reserved
d48
Discharge gas temp 3
Reserved
d49
Discharge gas temp 4
Reserved
d50
Compressor 3 Current
Reserved
d51
Compressor 4 Current
Reserved
d52
Main EEV 3
Reserved
d53
Main EEV 4
Reserved
d54
Auxiliary EEV 3
Reserved
d55
Auxiliary EEV 4
Reserved
2.3 System Fault Table 2
COD
E
Protection
Cause of Failure
Entry Condition
Fault Handling
E01
System
Shutdown
Wrong Phase
Wrong Phase
Check whether the three-phase wiring of
power supply is correct

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E02
System
Shutdown
Phase Loss
Phase Loss
Check whether the three-phase wiring of
power supply is correct
E03
System
Shutdown
Water Flow Switch 1
Protection
Water Flow Switch 1 open for 3
times in 1 hour
Check Water Flow Switch , water pump and
water pipe
E05
System
Shutdown
High Pressure Switch 1
Protection
High Pressure Switch 1 open for
3 times in 1 hour
Check manometers, heat exchangers, water
pump and water pipe
E06
System
Shutdown
Low Pressure Switch 1
Protection
Low Pressure Switch 1 open for
3 times in 1 hour
Check refrigerant, heat exchangers, and fan
motors
E07
System
Shutdown
High Pressure Switch 2
Protection
High Pressure Switch 2 open for
3 times in 1 hour
Check manometers, heat exchangers, water
pump and water pipe
E08
System
Shutdown
Low Pressure Switch 2
Protection
Low Pressure Switch 2 open for
3 times in 1 hour
Check refrigerant, heat exchangers, and fan
motors
E09
System
Shutdown
Communication Error
Communication failure between
mainboard and display panel
Check communication wire sequence,
connector and type
E10
System
Shutdown
Insufficient Water
Protection
Low Water Level Switch openfor
10 minutes
Check low water level switch,water pump
and water level in the tank
E11
System
Shutdown
Time Limitation Protection
Consult the manufacturer when
the probation period expires
Enter the correct password to unlock
E12
System
Shutdown
Discharge gas temp 1
protection
Discharge gas temperature 1
exceeds the setting
Check if discharge gas temperature exceeds
the setting
E13
System
Shutdown
Discharge gas temp 2
protection
Discharge gas temperature 2
exceeds the setting
Check if discharge gas temperature exceeds
the setting
E15
System
Shutdown
Water tank temp sensor
failure
Sensor short or open
Secure connector or replace sensor
E16
Failure
report
Evaporator coil temp
sensor 1 failure
Sensor short or open
Secure connector or replace sensor
E17
Failure
report
Evaporator coil temp
sensor 2 failure
Sensor short or open
Secure connector or replace sensor
E18
Failure
report
Discharge gas temp
sensor 1 failure
Sensor short or open
Secure connector or replace sensor
E19
Failure
report
Discharge gas temp
sensor 2 failure
Sensor short or open
Secure connector or replace sensor
E21
Failure
report
Ambient temp sensor
failure
Sensor short or open
Secure connector or replace sensor
E22
Failure
report
Return water temp sensor
failure
Sensor short or open
Secure connector or replace sensor
E23
Failure
report
Inlet water temp sensor
failure
Sensor short or open
Secure connector or replace sensor
E25
System
Shutdown
Water level switch failure
Water level switches misplaced
Place the switches in the correct positions
E26
System
Shutdown
Outlet water over
temperature protection
Outlet water temperature
exceeds setting
Check pipeline filter, valve and water pump
head
E27
Failure
report
Outlet water temp sensor
failure
Sensor short or open
Secure connector or replace sensor
E28
System
Shutdown
Insufficient water flow
Differential temp inlet/outlet
exceeds setting
Check water flow, water circuit and water
pump head
E29
Failure
report
Suction temp sensor 1
failure
Sensor short or open
Secure connector or replace sensor

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E30
Failure
report
Suction temp sensor 1
failure
Sensor short or open
Secure connector or replace sensor
E32
System
Shutdown
Low outlet water temp
protection
Outlet water temp lower than
setting
Check pipeline filter, valve and water pump
head
E35
System
Shutdown
Compressor 1 overcurrent
Compressor 1 current exceeds
setting
Check compressor current
E36
System
Shutdown
Compressor 2overcurrent
Compressor 2 current exceeds
setting
Check compressor current
E39
Failure
report
EEPROM error
Restore to factory settings
E50
E51
E52
E53
E54
Failure
report
Heating/cooling：after valve
sensor 1 failure
Hot water：Inlet water temp
sensor failure
Sensor short or open
Secure connector or replace sensor
E55
Failure
report
Heating/Cooling ：after
valve sensor 2 failure
Hot water：N/A
Sensor short or open
Secure connector or replace sensor
E56
E57
E63
E65
E66
E67
E68
E72
E73
E76
E77
E78

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E79
E89
E90
E95
E96
Note: 1. The temperature fault protection can be recovered automatically, and other fault protection must be restarted
by pressing 【ON/OFF】key.
2. In case of module fault, the number in front of E indicates the unit number in fault. For example, wh
en 2E09 is displayed, E09 communication fault occurs in unit 2.
3. Main board wiring diagram and dial code description
3.1 Model selection SW1 dial code setting description
SET ITEM
DIP1
DIP2
DIP3
DIP4
RESULT
REMARKS
Power Supply
OFF
1PH 220V
ON
3PH 380V
Check whether the three-phase is in
phase loss or out of phase
Spare
OFF
ON
Main Circuit
EEV
OFF
Regular
Do not detect suction temperature and the
temperature after the valve
ON
Superheat
Detect suction temperature and the
temperature after the valve
Model Selection
OFF
Heating/coo
ling
Do not detect water level. Make up valve
and return valve not valid.
ON
Hot water
Detect water level. Make up valve and
return valve valid.
Note:1) the dip switch is off on the digital side and on on the "ON" side;
2) when single-phase 220V is selected, three-phase protection will not be detected;
3) the DIP switch is only detected when the unit is powered on, and will not be detected after the unit is powered
on.
3.2 Module address SW2 dial code setting description
SET ITEM
DIP1
DIP2
DIP3
DIP4
Result
Remarks
Module address setting
（SW2)
OFF
OFF
OFF
OFF
1#Module
Mater
ON
OFF
OFF
OFF
2#Module
Slave 2
OFF
ON
OFF
OFF
3#Module
Slave 3
ON
ON
OFF
OFF
4#Module
Slave 4
OFF
OFF
ON
OFF
5#Module
Slave 5
ON
OFF
ON
OFF
6#Module
Slave 6
OFF
ON
ON
OFF
7#Module
Slave 7
ON
ON
ON
OFF
8#Module
Slave 8
Note: 1) the DIP switch is OFF on the digital side and ON on the "ON" side;

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2) the address code of the unit must be set before the unit is powered on. Ensure that the address codes o
f each unit are different; after power on, the dial switch will not be detected.
3) modular mode: 1 # the module is the master unit, which controls the water tank, water level, end switch a
nd circulating water pump; the slave machine does not connect to the display panel, otherwise the connected
display panel will report "E09" fault; the slave units does not detect the water tank, water level and end swit
ch.
4) singular mode: the address code of the main board shall be set as 1 #, otherwise the communication failu
re of "E09" will be reported.
3.3 Wiring diagram of main boards of modular units
3.3.1 description of unit free combination
All units are connected through the module interface communication bus, and the control board on the network is
connected in parallel. Each control panel can work independently or in combination with multiple control panels, and
can control up to 8 unit modules. The addresses of the units must be unique (i.e. different), and one unit address must
be set to 1 (i.e. master) and the others are slave. Each control board has the same function. The master and slave can
be set by dialing the module address on the control board. When the address dial code is set to 1, the unit is specified
as the master, and the rest addresses are all slaves.
In addition to the functions of the slave, the master also include the control functions of devices with [※] (table
below). The slave does not output or detect the above components. Therefore, the master is equivalent to the slave
plus additional control functions. The additional control functions are independent. If the master is shut down in case of
failure, the additional control functions will not be affected. That is to say, the master which is shutdown because of its
own failure will not affect the operation of the water heater system. Each module controller can be set as a master
module or a slave module. Only one controller is allowed to be set as the master module in a system, and the
controllers set as the slave modules can be added to the system at any time for operation, or can be detached from
the system for maintenance or inspection at any time.
The setting parameters of the modular units are shared.

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3.3.2 Modular Unit Energy Regulation Description
Energy regulation is determined by two factors:
➢Control temperature: water tank temperature
➢Control cycle；
The energy is regulated by the temperature area, and there are five areas in total: emergency start, loading,
holding, unloading and emergency stop.
When the control temperature is in the emergency start area, an energy level is loaded after every [control cycle
B10] time; when the control temperature is in the energy loading area, an energy level is loaded after every [control
cycle B11] time until all the energy is loaded; when the control temperature is in the energy holding area, the current
energy level is maintained without action; In the energy unloading area, unload one energy level every [control cycle
B11] time until all the energy is unloaded; when the control temperature is in the emergency stop area, unload one
energy level every [control cycle B10] time. The energy level is the units of the modular machines.
Note: when the modular machine or water heater is selected, the start and stop of the compressor is controlled by
the water tank temperature, and the current water temperature is the water tank temperature;
3.3.3 Division of cooling energy regulation area
No.
Digital Input
Digital Output
Analog Input
Analog Output
Special Interface
1
End switch ※
Enthalpy Valve
Ambient Temp
1#Main EEV
Display Panel interface 485
2
Water Flow Switch
1#Compressor
Outlet Temp
2#Main EEV
Modular Interface485
3
2#High Pressure
2#Compressor
Water Tank Temp※
1#Auxiliary EEV
Transformer primary
4
2#Low Pressure
External Fan Motor
Inlet Temp
2# Auxiliary EEV
Transformer secondary
5
1#High Pressure
4-way valve
1#Compressor Discharge
GasTemp
RS485 Interface 1
6
1#Low Pressure
Circulation Pump※
2#Compressor Discharge
GasTemp
RS485 Interface 2
7
Three Phase Detect
A
Electric
Heater
1# After Valve Temp (only in cooling)
8
Three Phase Detect
B
Crankcase
Heater
2#After Valve Temp
9
Three Phase Detect
C
Water Replenish Valve
1#Sutction Temp
10
Backwater Valve
2#Sutction Temp
11
Chasis Heating
2#Evaporator Coil Temp
12
2#Evaporator Coil Temp
13
1#Compressor Current
14
2#Compressor Current
15
High Water Level Signal※
16
Medium Water Level Signal※
17
Low Water Level Signal※
18
Return Water Temp（hot water only）
TSETC-b09 TSETC TSETC+P04 TSETC+P04+b08 T
Emergency Stop
Unloading
Holding
Loading
Emergency Start
Graph 1

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3.3.4 Division of heating energy regulation area
Note: TSETC: setting temperature in cooling; TSETH: setting temperature in heating;
P03 (parameter setting item): differential temperature in heating;
P04: differential temperature in cooling;
B08: differential temperature for return water in emergency start;
B09: differential temperature for return water in emergency stop;
B10: emergency start / stop control cycle (unit: Second);
B11: load / unload control cycle (unit: minute)
3.4 The connection method of GPRS module in modular units
A and B of the GPRS module interface of the master are respectively connected with A and B of the GPRS module
interface of the slave. The mode of connection with the main board of the module is similar. The GPRS module is
connected to the master. See the wiring diagram for the location of GPRS module interface.
3.5SHXK814G1 wiring diagram of single system of low temperature unit
Note: For heating/cooling model, CN12 is After valve sensor, P12 is Chassis heating. The water level switches K6, K7,
and K8 are invalid; For hot water model, CN 12 is Return water temp sensor, P12 is Water supply valve, the water
level switches K6, K7,and K8 are effective.
TSETH-P03-b08 TSETH-P03 TSETH TSETH+b09 T
Emergency Stop
Unloading
Holding
Loading
Emergency Start
Graph 2

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3.6SHXK814G2 wiring diagram of dual system of low temperature unit
Note: For heating/cooling model, CN 10 is After valve sensor 1, CN18 is After valve sensor 2. P14 is Chassis heating.
The water level switches K8, K9, and K10 are invalid; For hot water model, CN 10 is Return water temp sensor, CN18
is invalid, P14 is Water supply valve, the water level switches K8, K9, and K10 are effective.
4. Output description of replays
4.1 Compressor （220V/5A）
1) the compressor will not stop running due to energy load reduction within 3 minutes after starting, except in the
emergency stop area of energy regulation and fault protection;
2) the delay of 3 minutes (minimum standby time) must be met when the compressor is turned off and then
turned on.
4.2 Fan Motor（220V/10A）
1) Turn on the fan motor before starting the compressor;
2) Turn off the fan motor after the compressor shuts down;
3) In defrost mode, the fan motor is controlled according to the defrosting logic;
Fan-off unloading function: in the hot water mode, when the discharge gas temperature is ≥P15, (default
105 ℃) and the ambient temperature is ≥25 ℃, the fan turns off; when the discharge gas temperature is <
p15-5 ℃or the ambient temperature is ≤23 ℃, the fan turns. When the parameter setting value for P15 is set as
130, cancel this function.
4.3 4-way Reversing Valve（220V/5A）
1) the 4-way valve starts 10 seconds before the compressor starts (only in cooling mode);
2) the 4-way valve closes 2 minutes after the compressor shuts down.
4.4 Circulation Pump（220V/10A）
In hot water mode, the circulating pump operates as below.
1) before the compressor starts, the circulating pump starts in advance;

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2) after the compressor shuts down, the circulating pump is delayed to shut down.
3) when the temperature of the inlet water is too low and the pipeline is protected against freezing, the circulating
pump is forced to start.
4) in defrost mode, the circulating pump is forced to start.
In Heating and cooling mode: when the end switch is invalid, the circulating pump operates as the above. When
the end switch is effective, if the end switch opens, both the compressor and circulating pump are forced to stop. When
the end switch closes, if the water temperature reaches the set temperature and the parameter value in A09 is set to 0,
the circulating pump runs continuously when the unit is started, otherwise the circulating pump will run for A10 minutes
after it stops for A09 minutes
4.5 make up water valve (220V / 5A) (valid in hot water mode)
1)when the the high, middle and low water level switches are all disconnected, and the make-up valve is forced to
open. After 10 minutes, if the high, middle and low water level switches are still disconnected, the water shortage
protection is reported.
2) after the low water level switch is closed, the forced water replenishment is cancelled and the unit switches to
the temperature control water replenishment. When the water tank temperature is ≥setting temperature - P06 (when
the setting temperature is < 51 ℃, P06 is halved), the make-up valve is opened; when the water tank temperature is
≤setting temperature - P06 (when the setting temperature is < 51 ℃, P06 is halved) - P07, the make-up valve is
closed.
3) when the high, middle and low water level switches are closed, the make-up valve is forced to close. Only when
the high and middle water level switches are disconnected, can it be switched to temperature control water supply
again.
4) when the high water level switch is closed and the low water level switch is disconnected for 10 seconds, the
water level switch fault will be reported.
4.6 return valve (220V / 5A) (valid in hot water mode)
4.6.1 regular return water
1) in the hot water mode, when the return water temperature ≤parameter p08-5 ℃and the water tank
temperature is ≥parameter P08 + 5 ℃, turn on the return water function, when the return water temperature ≥
parameter P08, turn off the return water function.
2) the return valve will be opened only when the remote terminal has the function of timed return water and the
current time is within the set time range and the return water function is turned on.
4.6.2 temperature control return water
1) when the main board does not communicate with GPRS module for 10 minutes, turn on the temperature control
return function.
2) in the hot water mode, when the return water temperature ≤parameter p08-5 ℃, turn on the return water
function, when the return water temperature ≥parameter P08, turn off the return water function.
3) when the return water function is turned on, the temperature of the water tank must be higher than the
parameter item P08 + 5 ℃before the return valve is turned on.
4.7Electric Heater（220V/5A）
1) when the ambient temperature is ≤p09, the controller will check if the condition of electric heater is met.
When the ambient temperature is ≥p09 + 2 ℃, the electric heater is turned off
When the water temperature is ≤the set temperature - P10 (default 7 ℃), the electric heater is turned on;
When the water temperature is ≥the set temperature, the electric heater is turned off;
2) press and hold the [mode] key for 3 seconds to forced start the electric heater; (ambient temperature conditions
unnecessary to be met)

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When the water temperature is ≥the set temperature, the electric heating is turned off;
When the water temperature is ≤the set temperature - P10 (default 7 ℃), the electric heater is turned on;
3) when the master unit defrosts, the electric heater starts. When the unit enters the secondary anti freezing or
water tank anti freezing, the electric heater is turned on.
4) electric heater does not start in cooling mode.
4.8 enthalpy increasing valve (220V / 5A)
1) when the ambient temperature is ≤P11, the enthalpy increasing valve opens. When the ambient temperature
is ≥P11 + 2 ℃, the enthalpy increasing valve is forced to close.
2) the enthalpy increasing valve can be opened only after the compressor is started for 12 seconds. When the
compressor is closed, the enthalpy increasing valve is forced to close.
3) In cooling mode or defrost mode, the enthalpy increasing valve is forced to close.
As long as one system of the double system unit meets the requirements of opening the enthalpy increasing valve,
the enthalpy increasing valve will be opened.
4.9 Crankcase heater for compressor (220V / 5A)
1) when the ambient temperature is ≤5 ℃, the crankcase heater is turned on; when the ambient temperature is
≥8 ℃, the crankcase heater is turned off.
4.10 chassis heating (220V / 5A)
1) when the ambient temperature is ≤P14, and the compressor is turned in defrost, the chassis heating is
turned on.
2) when the ambient temperature is ≥P14 + 2 ℃or when it is in cooling mode, the chassis heating is turned
off.
4.11 water supply valve (220V / 5A) (effective in hot water mode)
1) when the display temperature is ≥parameter P08 + 2 ℃, the water supply function is activated.
2) after the water supply function is activated, if the remote end has turned on the timed water supply function
and the current time is within the set timed time range, the water supply valve is turned on.
3) if the display temperature is lower than the parameter item P08 -2 ℃, or the remote end does not turn on the
timed water supply function, or the timed water supply is turned on, but the current time is not within the set time
range, the water supply valve is closed.
4) when the low water level is disconnected, the water supply valve is closed.
5. Electronic expansion valve control logic
5.1 main circuit electronic expansion valve
1) after the compressor stops, the electronic expansion valve opens to the full open state, i.e. the maximum
number of pulses (parameter setting item L3) (settable, range: 230-254, default is 240, and the actual number of
pulses is the set value × 2);
2) 30 seconds after the compressor is started, in cooling mode the electronic expansion valve is opened to the
corresponding initial value L09, and the initial value in hot water / heating mode for electronic expansion valve is
L08;
3) when the electronic expansion valve is fully closed, it is 0 pulse, and when it is fully opened, it is the maximum
pulse;
The basic principle of opening the main circuit electronic expansion valve is as follows:
After the compressor is started, in hot water/ heating mode the system will detect the difference between suction
temperature and the coil temperature, and in cooling mode the system will detect the difference between the
suction temperature and the after valve temperature. Adjustments will be made according to the following rules.
The maximum opening during the adjustment process is L3, the minimum opening in cooling mode is L07, and the

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minimum opening in hot water or heating mode is L22 ~ L26. The adjustment interval time is L04 seconds. The
electronic expansion valve of each system works and adjusts independently;
Hot water / heating mode: △P = suction temperature –coil temperature –L22 ~ L26
Cooling mode: △P = suction temperature - temperature after refrigeration valve -L05
In hot water or heating mode, when the ambient temperature is not less than L14 and the water temperature is not
less than L15, △P = suction temperature - coil temperature - L13;
Restrictions on opening of main circuit electronic expansion valve:
①when the suction temperature is higher than L12, the value of the electronic valve increases gradually with 8
pulses, and it can reach the maximum value; when the suction temperature is lower than L12-2 ℃, it enters
normal regulation;
②when the discharge gas temperature of the compressor is ≥L10, the value of the electronic valve increases
gradually with 8 pulses, and it can reach the maximum value; when the discharge gas temperature of the
compressor is ≤L10 ℃, it exits this regulation;
③when the discharge gas temperature is higher than L11, the value of the electronic valve increases gradually
with 8 pulses, and it can reach the maximum value; when the discharge gas temperature is lower than L11-2 ℃, it
enters normal regulation;
Note: the superheat and the minimum opening of the electronic expansion valve of the main circuit are divided
into 5 areas according to the table below.
5.2 auxiliary electronic expansion valve
1) after the enthalpy increasing valve closes, the electronic expansion valve of the auxiliary circuit will fully close;
2) after the enthalpy increasing valve opens, the auxiliary electronic expansion valve will open to the initial opening
set in parameter L16. After the compressor starts for 2 minutes, If inlet water temperature and discharge gas
temperature are detected, the opening of the EEV will be adjusted according to the following rules. The maximum
opening is 60 and the minimum opening is L17. The adjustment interval time is L4 seconds;
△P = discharge gas temperature –inlet water temperature - 35 ℃- L18;
When | △p| = 2, the electronic expansion valve of the auxiliary circuit maintains the current opening.
6. Logic of defrost control
This function is only valid in hot water mode or heating mode;
6.1 conditions for defrosting
1) when the ambient temperature is ≥H08 (default - 6 ℃) + 1 ℃, coil temperature is ≤H02 (default -
-17 -15 -10 -8 -4 -2 3 5 Ambient (℃)
A ZONE
B ZONE
C ZONE
D ZONE
E ZONE

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3 ℃), ambient temperature is ≤H01 (default 15 ℃), and the compressor is running, time counting starts,
when timing is ≥H04 (default 60 minutes);
2) when the ambient temperature is ≤H08, the cumulative operation time of the compressor is ≥H12 (default
90 minutes) ;
3) ambient temperature - coil temperature is ≥H09;
4) the compressor runs continuously for 6 minutes;
If anysystem meets the above conditions of 1, 3, 4 or 2, 3 and 4 at the same time, both systems will enter defrost
at the same time, and the display panel will display defrost icon.
6.2 defrost exit conditions
1) coil temperature ≥H03 (default 16 ℃) for 30 seconds;
2) defrost operation time ≥H05 (default 8 minutes);
3) high pressure protection;
4) compressor current ≥B01 for 5 seconds;
5) the outlet water temperature is less than 5 ℃for 10 seconds;
If one system meets any of the above conditions, the compressor stops, and if both systems meet any of the above
conditions, the unit will exit defrost.
6.3 defrost operation process
Enter defrost - compressor off - external fan off, 4-way valve on - compressor on;
6.4 defrost exit process:
Defrost exit conditions satisfied - compressor off - external fan on - 4-way valve off - compressor on, defrost icon on
display panel removed (only valid when querying this unit).
6.5 forced defrost
Enter the parameter query state, select the address of the unit to be forced defrosted, and in the query unit state, press
and hold the [query / time] + [timing / confirmation] key for 5 seconds. This unit enters into forced defrost operation,
and defrosting symbol flickers.
1) when the system enters defrost, the panel displays [defrosting];
2) operation conditions: in hot water/heating mode only;
Note: during defrosting, there is no need for coordination between modules. As long as defrosting conditions are met,
the module unit will enter defrost; for modules entering defrost, two systems will enter defrost synchronously.
When H07 is set to - 5, the unit defrosts according to the default conditions.
When H07 is not set to - 5, and the ambient temperature ≤H07, the unit does not defrost.
7. System Protections
7.1 phase loss and reverse phase protection
1) when the three-phase input is out of phase or of wrong phase, it will enter the unit protection state. When the
three-phase input is normal, the unit will exit the protection state and enter the normal operation state.
2) the phase loss and wrong phase protection can be selected, which can be turned on or cancelled through the
dial switch SW1-1 on the main board.
7.2 high pressure protection
1) when the high pressure switch is detected to be open for 5 seconds, the unit will stop and display the fault code.
When the high pressure switch is detected to be closed, the unit will start (the compressor must meet the
requirement of 3 minute delay).
2) when the high pressure switch is detected to be open for three times within one hour or for a continuous 30
minutes, the unit will enter protection and display the corresponding fault code.
7.3 low pressure protection

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1) when the low pressure switch is detected to be open for a continuous 10 seconds, the unit will stop. When the
low pressure switch is detected to be closed, the unit will start (the compressor must meet the requirements of 3
minute delay).
2) when the low pressure switch is detected to be open for three times within one hour or for a continuous 30
minutes, the unit will enter the unit protection and display the corresponding fault code.
3) however, in the delay time (default is 5 minutes) of P16 after the compressor is started, and in defrost mode,
the system will not detect low pressure switch.
7.4 water flow switch protection
1) after the circulating pump runs for 60 seconds, the system starts to check the water flow switch status. If it is
detected to be disconnected for a continuous 5 seconds, the unit will shut down and enter the protection state,
displaying the fault. After 3 minutes, the unit exits the protection can be restarted;
2) if the protection occurs three times in 1 hour, the unit will be shut down and locked, displaying failure code.
7.5 linkage protection function of end switch (effective in heating/cooling mode)
When parameter A05 is set to “1”, the end switch is invalid: the circulating pump starts and stops following the
compressor.
When parameter A05 is set to “0”, the end switch is effective.
A. If the end switch is closed, the circulating pump is running continuously, and the compressor starts/stops
according to water temperature conditions.
B. If the end switch is open , both the circulating pump and the compressor will stop.
If the end switch is open, the unit stops and the "unit" symbol on the display flickers.
7.6 temperature difference protection for insufficient water flow
1) in cooling mode, after the circulating pump is started for 60 seconds, if inlet water temperature –outlet water
temperature is ≥B03 (default is 15 ℃) for a continuous 10 seconds, the unit will shut down and enter the protection
state, displaying the fault;
2) in the hot water / heating mode, after the circulating pump is started for 60 seconds, if outlet water temperature
- inlet water temperature is ≥B03 for a continuous 10 seconds, the unit will stop and enter the protection state,
displaying the fault;
3) if there are three times of insufficient water flow temperature difference protection within one hour, the unit will
be shut down and locked, indicating failure.
7.7 outlet water over temperature protection
1) in hot water / heating mode, 60 seconds after the circulating pump is started, if the outlet water temperature is
≥B04 (default is 70 ℃) for a continuous 5 seconds, the unit will stop. When the outlet water temperature is ≤
B04 - 10 ℃for a continuous 30 seconds, the unit will exit protection and can be started again;
2) if the protection occurs three times in 1 hour, the unit will stop and enter the protection state, displaying the
fault;
7.8 low outlet temperature protection
In cooling mode, 50 seconds after the circulating pump starts, if the outlet water temperature is ≤B05 (default is
5 ℃) and lasts for 5 seconds, the unit will stop. When the outlet water temperature is ≥B05 + 4 ℃and for a
continuous 30 seconds, the unit will exit protection and can be started again;
7.9 pipeline level I anti freezing protection
When the outlet water temperature or water inlet temperature is ≤5 ℃for a continuous 10 seconds, the unit
enters the pipeline antifreeze protection. After the circulating pump runs for 1 minute, if the outlet water temperature is
≥7 ℃for a continuous 10 seconds, the unit exits the pipeline level I antifreeze protection. Any unit failure does not
affect the antifreeze protection (except for the three-phase protection).
7.10 pipeline level II anti freezing protection (heating/cooling mode)