Specifications

SiUS39-601 Troubleshooting by Indication on the Remote Controller
Troubleshooting 181
2.47 “U7” Indoor Unit: Malfunction of Transmission Between
Outdoor Units
Remote
Controller
Display
U7
Applicable
Models
All models of indoor units
Method of
Malfunction
Detection
Microcomputer checks if transmission between outdoor units.
Malfunction
Decision
Conditions
When transmission is not carried out normally for a certain amount of time
Supposed
Causes

Improper connection of transmission wiring between outdoor unit and external control adaptor
for outdoor unit.

Improper cool/heat selection

Improper cool/heat unified address (outdoor unit, external control adaptor for outdoor unit)

Defect of outdoor unit PC board (A1P)

Defect of external control adaptor for outdoor unit

Improper connection of transmission wiring between outdoor units.