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431

Alert Code 431 — PFC fault

Lennox · Communicating Systems

What does 431 mean?

The inverter's power factor correction circuit has detected an over-current. This causes the compressor and fan to stop. Frequent occurrences will lead to a system lockout.

Common Causes

  • PFC circuit over-current detected
  • High peak current reading

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Disconnect power to the outdoor unit.

  2. 2

    Reconnect power to the outdoor unit and restart the system.

Browse all codes in this manual (41)
Verified technical data. Last updated: April 2026

Related Faults

14Inverter Flash Code 14 (Red 1 flash, Green 4 flashes) — OD Inverter Compressor Slowdown21Inverter Flash Code 21 (Red 2 flashes, Green 1 flash) — OD Inverter DC Peak Fault262 red flashes, 6 green flashes — Compressor startup fail
Source: Lennox Communicating Systems
Open Manual (Page 59)Search more codes in this manual