Brand: Fujitsu
Category: Air Conditioners
Document Type: Manual
Language: EN
Manual for ASU18RLF
Uploaded: Nov. 21, 2025, 9:01 p.m.
Warranty Information
This manual does not contain explicit warranty period information.
This manual provides detailed specifications and technical information for Fujitsu Inverter Multi Air Conditioners. It includes data on outdoor and indoor units, refrigerant charge, dimensions, electrical data, fan motor specifications, and noise levels. The manual also details refrigerant system diagrams, circuit diagrams, and error detection codes for troubleshooting. It lists parts and accessories for various indoor and outdoor units, along with installation instructions and wiring schematics.
Troubleshooting and error codes
| LED 1 | LED 2 | LED 3 | LED 4 | ||
| Serial communication error (outdoor unit to indoor unit A) | 1 time | — | — | — | |
| Serial communication error (outdoor unit to indoor unit B) | — | ● 1 time | — | — | |
| Serial communication error (outdoor unit to indoor unit C) | — | — | ● 1 time | — | |
| Serial communication error (outdoor unit to indoor unit D) | — | — | — | ● 1 time | |
| Discharge thermistor error | ● 2 times | — | — | — | |
| Outdoor unit, heat exchanger (middle) thermistor error | ● 3 times | — | — | — | |
| Outdoor thermistor error | ● 4 times | — | — | — | |
| 2-way valve thermistor error (indoor unit A) | — | ● 5 times | — | — | |
| 2-way valve thermistor error (indoor unit B) | — | — | ● 5 times | — | |
| 2-way valve thermistor error (indoor unit C) | — | — | — | ● 5 times | |
| 2-way valve thermistor error (indoor unit D) | — | — | — | — | ● 5 times |
| 3-way valve thermistor error (indoor unit A) | ● 6 times | — | — | — | |
| 3-way valve thermistor error (indoor unit B) | — | ● 6 times | — | — | |
| 3-way valve thermistor error (indoor unit C) | — | — | ● 6 times | — | |
| 3-way valve thermistor error (indoor unit D) | — | — | — | ● 6 times | |
| Compressor thermistor error | ● 7 times | — | — | — | |
| Heatsink thermistor error | ● 8 times | — | — | — | |
| High pressure switch 1 error | ● 9 times | — | — | — | |
| High pressure switch 2 error | ● 10 times | — | — | — | |
| Indoor unit capacity error | ● 11 times | — | — | — | |
| Trip detection | ● 12 times | — | — | — | |
| Compressor roter position detetion error | ● 13 times | — | — | — | |
| Trip terminal L error | ● 14 times | — | — | — | |
| Outdoor unit fan motor error | ● 15 times | — | — | — | |
| Outdoor unit PCB microcomputer communication error | ● 17 times | — | — | — | |
| Discharge temperature error | ● 18 times | — | — | — | |
| Compressor temperature error | ● 19 times | — | — | — | |
| 4-way valve error | ● 20 times | — | — | — | |
| Outdoor unit PCB model information error | ● 21 times | — | — | — | |
| Active filter error, PFC circuit error | ● 22 times | — | — | — |