Haier AB422XCBAA Service Manual page 131

communication resumes normal, it can enter normal operation and cancel the failure.
When all indoor units can not communicate normally, it shows communciation
malfunction.
8.2.2.4 Solenoid valve control with single unit in cooling mode
If indoor unit sends the "start-compressor" signal, the corresponding solenoid valve will
open; when shutting off the compressor, the corresponding solenoid valve will close. If the
indoor units in one system all send the "stop-compressor" signal, the solenoid valve last
receiving signal will close 3 minutes later.
8.2.2.5 Solenoid valve control with single unit in heating mode
If indoor unit sends the "start-compressor" signal, the corresponding two solenoid valves
will open; if there is only one indoor unit, the two valves will open too.
8.2.2.6 When double units of one system are in cooling mode, if the two indoor units send
the "start-compressor" signal, the two solenoid valves will open; if one indoor sends
"start-compressor" signal, while the other sends "stop-compressor", then the solenoid
valve will open or close respectively. If the two units all send "stop-compressor" signal, the
solenoid valve will open for 3 minutes after compressor stops.
8.2.2.7 When double units of different system are in cooling mode, if the indoor unit sends
the "start-compressor" signal, the corresponding solenoid valves will open; If the unit
sends "stop-compressor" signal, the corresponding solenoid valve will open for 3 minutes
after compressor stops.
8.2.2.8 When double units of one system are in heating mode, if any of the two indoor
units sends the "start-compressor" signal, the two solenoid valves will open. After
compressor stops, the solenoid valve will close 3 minutes later.
8.2.2.9 When double units of different system are in heating mode, if one indoor unit of
one system sends the "start-compressor" signal, the two solenoid valves of this system
will open. After compressor stops, the solenoid valve will close 3 minutes later.
8.2.2.10 The treatment for 1 to 3 or 1 to 4 refers to the different combination of the above
1-7 items.
8.2.2.11 Treatment for anti-freezed function
When the two systems are in operation, if one system enters anti-freezed function, the
compressor of this system will stop, while the outdoor motor and the other system will
work normally. If the two systems all enter anti-freezed function, outdoor unit will stop
operation, at this moment if one system resumes, outdoor motor and the corresponding
system will work normally. The compressor of the system which does not resumes will
stop.
8.2.2.12 Treatment for overheating function
The treatment of stop-compressor status is identical to that of anti-freezed status. If one
system enters overheating 3, this system will stop, while the outdoor motor and the other
system will work normally. If the two systems enter overheating 3, the outdoor will stop; at
this moment if one system resumes, outdoor motor and the corresponding system will
work normally. If the indoor units of the two systems all enter the overheating 2, outdoor
motor will stop. The outdoor will not deal with the status of overheating 1.
Note: The overheating point is decided by the indoor unit.
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