24VNA6 / 25VNA4 seriesCarrier 81 fault code (24VNA6 / 25VNA4)
PFC Error; Unbalanced PFCM Error; VFD System Wiring Error
What the manual says
PFC Error; Unbalanced PFCM Error; VFD System Wiring Error
| Fault | Malfunction | Description |
|---|---|---|
| 13 | 53 | PFC Error |
| 14 | 54 | Unbalanced PFCM Error |
| — | 58 | VFD System Wiring Error |
Models and series
Listed for: 24VNA6, 25VNA4.
Troubleshooting from the service manual
Code 81-13 VFD System Fault - PFC / Code 81-53 VFD System Lockout - PFC
The power factor correction circuit (PFC) in VFD introduces an inductance which corrects the current phase shift inherent with powering motors. This in turn minimizes the reactive power transmitted back to input power cables. This fault is set when the PFC circuit exceeds a peak current limit when driving compressor. System will shut down and VFD will reset, if demand persists, system will attempt to resume normal operation. After 2 occurrences within 10 minutes, code 81-53 is set and system is locked out for 4 hours. A power cycle will clear malfunction lockout timer. Continued malfunctions indicate high current situation. This is likely due to VFD or compressor damage. Measure reactor(s) resistance. As reactor charges the resistance will be reduced to 0. If measurement is open, replace reactor. Otherwise replace VFD.
24VNA6-25VNA4-1SM, p. 21
Code 81-14 VFD System Fault - Unbalanced PFCM / Code 81-54 VFD System Lockout - Unbalance PFCM
Applicable to 4 and 5 ton models only with multiple reactors. This fault occurs when current in PFCM circuits is not balanced. It is most likely caused by a disconnected or faulty reactor. The VFD will shut down and attempt to restart after each occurrence of code 81-14. After 2 occurrences within 10 minutes, code 81-54 is set and system is locked out for 4 hours. Disconnect and measure resistance of both reactors in system. As reactor charges the resistance will be reduced to 0. If measurement is open, replace reactor. Otherwise replace VFD.
24VNA6-25VNA4-1SM, p. 21
Code 81-58 VFD System Lockout - Wiring Error
This fault occurs when the VFD senses that 1 or more of the compressor wires are not connected to VFD. While this fault is active the system is inoperable. Check compressor wire harness at each end and ensure connections are tight fitting and wires are undamaged. Perform continuity test on compressor harness with DMM. Check resistance of compressor windings at VFD end of compressor harness to ensure no windings are open. Refer to Table 3 for compressor winding resistance by outdoor model.
24VNA6-25VNA4-1SM, p. 21
Source
24VNA6-25VNA4-1SM, p. 26
81 | 13 | 53 | PFC Error | 14 | 54 | Unbalanced PFCM Error | | 58 | VFD System Wiring Error
Last checked 2026-10-18 against 24VNA6-25VNA4-1SM.
Safety: disconnect power before opening the unit. Gas, high voltage and refrigerant work belongs to a licensed technician.