Brand: MITSUBISHI ELECTRIC
Category: Air Conditioner
Document Type: Installation Guide
Language: EN
Installation Guide for MSZ-FS12NA
Uploaded: Nov. 21, 2025, 8:02 p.m.
Basic Operation
This manual covers the installation of the MITSUBISHI ELECTRIC MSZ-FS12NA air conditioner. It details safety precautions, installation location selection, power supply and wiring, refrigerant pipe preparation, and the purging, leak testing, and test run procedures. It also includes instructions for setting the installation position for the remote controller and basic explanations for the user.
Troubleshooting and error codes
| Problem | Possible Cause | Remedy |
|---|---|---|
| Operation does not start. |
1. Power supply plug is not inserted, or breaker is off. 2. Remote controller is not operated correctly. 3. Auto restart function is set. |
1. Insert plug, or turn on breaker. 2. Refer to the operating instructions. 3. Press the E.O. SW once for COOL, or twice for HEAT operation. (Refer to operating instructions) |
| Indoor/outdoor unit connecting wire (A) is mis-wired. | Check indoor/outdoor unit connecting wire (A) for mis-wiring. | Consult the installation manual. |