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40
COMMUNICATION SIZES 48−56
Detection of the quantity of installed indoor units and Branch Box (BU) modules: After 3 minutes of energizing, if the outdoor unit does
not receive the communication data of a certain indoor unit, the outdoor unit determines the indoor unit is not installed and interacts with the
unit accordingly. If the outdoor unit receives the communication data from the same indoor unit later, the outdoor unit interacts with that unit
as if it is installed.
NOTE: If the number of indoor units are not detected automatically, push SW5 for addressing.
TESTING BOARD INSTRUCTION SIZES 48−56
Testing Board
The testing board is located in front of the electrical box. The testing board provides the following benefits:
S
Detects indoor unit numbers and indoor unit address
S
Displays real running functions and error codes automatically.
It is composed of the function section, data section and button section.
Function section
Data section
Button section
Function
Fig. 80 – Testing Board
Table 41—Function Instruction and Data Section
Running State
Function Section Display
Data Section Display
Stop
1 The section displays the numbers of the indoor units
which have established communication with the
outdoor unit. For example, if there are sever
established indoor units, the section displays “7”.
2 It displays the address of the indoor units (“1b”
represents the indoor unit 1B). (Branch Box
module:1/2/3, Indoor unit: A/b/C/d/E)
1 If the function section
displays the indoor units'
numbers, the data section
displays the outside
temperature. For
example, “95” represents
95
_
F (35
_
C).
2 If the function section
displays the indoor unit's
address, the data section
displays the model of the
indoor unit (“35”
represents the 35 model).
Normal
The running state code:
Displays the target gear of the
compressor. If the gear is zero, it
displays “0”.
For example, the gear is the 15
th
, it
displays “15”. The gear range is 0 -
60.
Code
Running state
Code
Running state
UE
Pressure
Equalization
UH
Heating
UP
Pump Down
F7
Oil Returning
UC
Cooling
H1
Defrosting
Malfunction
If the malfunction occurs in the system, the section displays the
error code. If there are several malfunctions, it displays the
error codes at intervals of 2 seconds.
1 If the malfunction occurs
in the outdoor unit, the
section displays nothing.
2 If the malfunction occurs
in the indoor units, the
section displays the
indoor unit's address.