24 | Troubleshooting
Installer and user reference guide
158
REYQ8~20+REMQ5U7Y1B
VRV IV+ heat recovery
4P561154-1A – 2020.10
Main code Sub code Cause Solution
Master Slave 1 Slave 2
INV1 unbalanced power supply
voltage
Check if power supply is within
range.
INV2 unbalanced power supply
voltage
Check if power supply is within
range.
Reversed power supply phase
malfunction
Correct phase order.
Reversed power supply phase
malfunction
Correct phase order.
INV1 voltage power shortage Check if power supply is within
range.
INV1 power phase loss Check if power supply is within
range.
INV2 voltage power shortage Check if power supply is within
range
INV2 power phase loss Check if power supply is within
range.
Malfunction code: system test
run not yet executed (system
operation not possible)
Execute system test run.
An error occurred during the
test run
Re-execute the test run.
, Test run aborted Re-execute the test run.
, Test run aborted due to
communication issues
Check the communication wires
and re-execute the test run.
Faulty wiring to Q1/Q2 or
indoor - outdoor
Check (Q1/Q2) wiring.
Indoor unit communication
error
Check user interface
connection.
, Malfunction code: faulty wiring
to Q1/Q2
Check Q1/Q2wiring.
Too many indoor units are
connected to F1/F2 line
Check indoor unit amount and
total capacity connected.
System mismatch. Wrong type
of indoor units combined
(R410A, R407C, Hydrobox, etc)
Indoor unit malfunction
Check if other indoor units have
malfunction and confirm indoor
unit mix is allowed.