General Assist Technical Reference
DIP Switches – Series Indoor Units
Indoor unit capacity setting – SW4
VRF indoor unit PCB replacement and capacity configuration reference
Key point: When replacing any board on a VRF system, the DIP switches on the replacement board must be set exactly the same as the original board unless the applicable service documentation specifically instructs otherwise.
Important: SW4 sets the indoor unit capacity. If SW4 is not set correctly, the indoor unit capacity will default to 2.5 kW / 7,000 BTU.
SW4 indoor unit capacity settings
Use the table below to configure SW4-1 to SW4-4 for the required indoor unit model capacity.
| SW4 | 60 | 54 | 45 | 36 | 30 | 25 (24) | 20 | 18 | 14 | 12 | 9 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SW4-1 | ON | OFF | ON | OFF | ON | OFF | ON | OFF | ON | OFF | ON | OFF |
| SW4-2 | ON | ON | OFF | OFF | ON | ON | OFF | OFF | ON | ON | OFF | OFF |
| SW4-3 | OFF | OFF | OFF | OFF | ON | ON | ON | ON | OFF | OFF | OFF | OFF |
| SW4-4 | ON | ON | ON | ON | OFF | OFF | OFF | OFF | OFF | OFF | OFF | OFF |
Board replacement procedure
- Before removing the original PCB, record or photograph every DIP switch position.
- Confirm the indoor unit model/capacity before setting SW4 on the replacement PCB.
- Set SW4-1, SW4-2, SW4-3 and SW4-4 exactly as shown for the applicable capacity.
- Copy all other DIP switch settings from the original board.
- Recheck the settings before restoring power to the system.
Service tip: Incorrect DIP switch settings can cause the replacement PCB to identify the indoor unit incorrectly. If a board has been replaced and the system operation or reported capacity is abnormal, compare the DIP switch positions against the original board and the applicable service manual.
Quick reference
| Switch bank | SW4 |
| Function | Indoor unit capacity setting |
| If not set | 2.5 kW / 7,000 BTU capacity |
| PCB replacement | Match the DIP switch settings of the original PCB exactly. |