Haier Arctic Multi 2U20EH2VHA Reference manual

DFS05-19
DFS05-19
Multi-Split Communication Wiring Check
The FlexFit Multi and Arctic multi systems are capable of performing a self-test to check
communication wiring between the outdoor to the indoor units. This is a crucial step when performing
start-up on a system as well as performing checks during a service call. It allows you to confirm that
the wiring matches with the associated refrigerant lines for a given circuit.
Arctic Multi 2U20EH2VHA
3U24EH2VHA
FlexFit Multi 3U24MS2VHB
4U36MS2VHB
1
Models affected:
Instructions:
1. Disconnect power to the outdoor unit.
2. Set Dip Switches SW1-1, SW1-2, SW1-3 &
SW1-4 to the ON position. These dip
switches are located on the Service Monitor
Board. (pictured right).
3. Turn ON power to the outdoor unit.
JUNE 2019
Service Bulletin
SW1

Testing Process:
1. All indoor fans will come on at HIGH fan speed.
2. EEV for Circuit A will open.
3. All other EEV’s will close.
4. After a 3 minute delay, the Compressor will start and ramp up to 55HZ.
5. The digital display will alternately display “CH” and “Compressor Frequency (HZ)” at
5-second intervals (pictured below).
6. The system will circulate refrigerant through Circuit Afor about 10 minutes.
7. Afterwards, Circuit A’s EEV will close and Circuit B’s EEV will open.
8. This process will be repeated for each indoor unit that is connected.
2
Service Bulletin
JUNE 2019
DFS05-19
DFS05-19

Testing Process (continued):
9. Once all indoor units have been checked, the digital display will show either “EC” or “0”
•“EC” indicates there is an error in the wires to the indoor unit(s).
•The LED(s) will be flashing, indicating which circuit(s) has the fault.
•For example, if the wires for circuit A and B are switched, then LED1 and
LED 2 will flash.
•Once the wiring is corrected, re-run this test to confirm everything is functional.
o“0”indicates that all wiring is correct.
oIf all the wiring is correct, the LED’s remain solid.
10. Once the test is complete, make sure to change the dip switches back to the OFF
position.And set each indoor unit to preferred set points.
3
Service Bulletin
JUNE 2019
DFS05-19
DFS05-19