Haier 2U18MS2HDA1 Installation Instructions Manual page 19

INSTALLATION INSTRUCTIONS
Step 3 - Installation of the Outdoor Unit (Cont.)
D. Wiring Check Test
Turn off power at the disconnect. Move all dip
switches in the SW1 bank to ON. When power is turned
on, the LED display will alternate the compressor
frequency and CH (check). The system will run through
each unit (A, B, and C), cycling each EEV while testing
the wiring. A successful test will be indicated by the
corresponding LED displaying a constant green (1=A,
2=B, 3=C). Mis-wired units will generate an EC on the
display, with the corresponding LED flashing green.
LED A B
ALL Flashing
LED status
example for
3U24MS2HD*
ON Flashing Flashing
model
Model
Connection priority
is largest indoor unit
on lowest terminal
set (D), and install
remaining indoor units
from bottom to top.
When there are two
indoors, the prior
service valves are
When there are three
indoors, the prior
service valves are
When there are four
indoors, the prior
service valves are
NOTE: Please execute as the above when connecting indoor unit for better oil return and more reliable system.
NOTE: No connection priority on 4U36EH2VHA1
31-5000564 Rev. 1
C D E
OFF
ALL ON
ON Flashing ON: unit connected correctly
Only one LED flashing
Line Set Connections
4U36MS2HDA1 3U24MS2HDA1
D C C B
D C B C B A
D C B A
Message
No power to unit
Outdoor unit searching for indoor units at initial start-
up. If flashing continues, check wiring for proper type and
connections
All units connected correctly
Flashing: IDU not communicating. Check wiring and
connections among B, C & E
2U18MS2HDA1
B A
/
/ /
Note: This LED display layout only
applies to 4U36MS2HDA1
2U20EH2VHA 3U24EH2VHA
B A C B
/ C B A
/ /
19