Troubleshooting by Indication on the Remote Controller
SiUS30-1301
222
Service Diagnosis
3.43 Transmission Error between Condensing Units
Error Code
U7
Applicable
Models
RWEYQ72P, 84P
Method of Error
Detection
Micro-computer checks if transmission between condensing units is normal.
Error Decision
Conditions
When transmission is not carried out normally for a certain amount of time
Supposed
Causes
Improper connection of transmission wiring between condensing unit and external control
adaptor for condensing unit.
Improper connection of transmission wiring between condensing units
Improper cool/heat selection
Improper cool/heat unified address (condensing unit, external control adaptor for condensing
unit)
Defective condensing unit PCB (A1P)
Defective external control adaptor for condensing unit
Defective fuse of condensing unit compressor