Daikin VRV IV+ Service Manual page 178

2 | Troubleshooting
2.3.185 UA-35 – Combination abnormality - REMQ-U Unit Detected in Wrong Combination
2.3.186 UA-38 – Combination abnormality - Altherma hydro unit detected
Service manual
178
Possible cause: REMQ-U unit installed as standalone unit.
4 Perform a check of the main PCB of the main outdoor unit. See
4
PCB" [ 290].
Possible cause: Faulty main PCB of the main outdoor unit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Trigger
REMQ Unit detected in a
Not-Allowed combination
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1 REMQ Units are only allowed in multi combination as REMQ5U + REMQ5U or
REMQ8U + REMQ5U.
Possible cause: REMQ-U unit installed in a not-allowed multi combination.
2 Check the Q1‑Q2 communication between the outdoor units in multi
combination. See "4.1 Electrical
Possible cause: Faulty wiring.
3 Perform a check of the main PCB of the main outdoor unit. See
4
PCB" [ 290].
Possible cause: Faulty main PCB of the main outdoor unit.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
Trigger
Main PCB on main
outdoor unit detects
Altherma hydrobox on F1-
F2 IN wiring.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1 Only LT Hydrobox HXY-A and HT Hydrobox HXHD-A are allowed in the
installation. See the Databook for more information.
Effect
Unit will stop operating
4
circuit" [ 356].
Effect
Forced stop.
"3.11 Main
Reset
Power reset at outdoor
unit.
"3.11 Main
Reset
Automatic reset after re-
initialization detects
compatible units.
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05