Error Code General Information - LG Multi V5 Service Manual

Please refer to the Safety Precautions on pages 4-7 for more detail to prevent injury or death regarding the operation and service
WARNING
troubleshooting of the Multi V product.
General Information
LG VRF system's core logic uses error codes to indicate that an abnormal operation occurred. Error codes help guide a trained service tech-
nician to identify why and what caused the error to display, and help track the frequency of malfunction occurrences.
There are four (4) levels of error code responses; the system responds accordingly, depending on the severity of the malfunction assigned to
the malfunction. The level of responses range from "notify and keep operating" (Level 4), to "immediate system shutdown" (Level 1).
All error codes can be viewed at the outdoor unit seven segment display (SSD) and with LGMV software. If an error codes shows on one
(1) or more indoor unit zone controllers, it will display on LGMV, central controllers, BMS, or any other LG device connected to Comm bus -
Internet A/B. Indoor unit error code notifications will display differently based on location of the problem.
Level 4 Responses
Level 4 responses display the error code, but the system continues to operate (operate indefinitely). When the malfunction is fixed, the error
code remains until the master outdoor unit's microprocessor is reset, and operation has resumed for 130 minutes without the malfunction
reoccurring.
Level 3 Responses
Level 3 responses display the error code on all zone controllers, central controllers, and on BMS systems. For Level 3 responses, the Multi V
system will shut down for three (3) minutes, and then the master microprocessor in the outdoor unit will automatically restart the system.
If the malfunction reoccurs up to a total of nine (9) times within one (1) hour, the system will display the error code, shut down, and restart
again each time. If the malfunction occurs a tenth (10th) time within the same one (1) hour, the system shuts down permanently, assigning
the error to a Level 1 response that requires a manual restart. The error code displays on the zone controllers and central controllers until the
malfunction is fixed.
Level 2 Responses
Level 2 responses are communications related errors only. Level 2 responses activate after ten (10) attempts to communicate have occurred.
After communications have been re-established, the error codes display for one (1) minute. If the communications are restored, then the
error code disappears. If the communication is lost within one (1) minute, the error code remains.
Error codes for Level 2 responses stop appearing on the zone and central controllers as soon as communications are restored, without the
need to reset power at the Master outdoor unit or to restart the entire system.
Multi V 5 error codes for Level 2 responses appear where the problem occurs, and time limits differ depending on type:
1. Communications lost between outdoor unit PCBs – no time delay.
2. Communications lost between the indoor unit and the outdoor unit for three (3) minutes.
3. Communications lost between the indoor unit and heat recovery unit for ten (10) seconds.
4. Communications lost between outdoor unit external PCBs for ten (10) seconds.
Level 1 Responses
Many Level 1 responses call for an immediate system shutdown, and, in almost all abnormal operational situations, occur after the algorithm
monitoring system verifies that the malfunction is real (to avoid nuisance alarms and false positives). Level 1 responses are displayed at
zone controllers, central controllers, BMS, LGMV, and the outdoor unit SSD. They cannot be cleared until the problem that caused it is fixed.
Before a Level 1 response is assigned, the Multi V algorithm initially assigns a Level 3 response to any system malfunction that is not
communications related. The system follows Level 3 protocol until the tenth (10th) time a malfunction occurs, at which time the system shuts
down, the malfunction changes from Level 3 to Level 1, and a manual restart is required. The entire Level 3 auto restart to Level 1 shut down
sequence will repeat until the malfunction is fixed.
For more information on Multi V Levels and error codes, see the troubleshooting pages in this section, and contact an LG trained technician.
Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. "LG" is a registered trademark of LG Corp.
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