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188

Alarm 188 - Inverter High Level Alarm

Lennox · PRODIGY 2.0 Unit Controller

What does 188 mean?

The inverter has detected a high-level issue, such as peak DC current, maximum current lockout, low DC link voltage, locked rotor, or high DC link voltage. The compressor will stop temporarily.

Common Causes

  • Inverter error code detected
  • Peak DC current reached
  • Maximum current lockout
  • Low DC link voltage
  • Locked rotor condition
  • High DC link voltage
  • Low outdoor ambient temperature lockout
  • High heat sink temperature lockout
  • Low input voltage

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    No immediate action is typically required; the compressor stops for a minimum run time.

  2. 2

    If the unit shuts down after ten occurrences in one hour, Alarm 189 will be initiated.

  3. 3

    The alarm will automatically clear when the inverter error condition is resolved.

  4. 4

    Refer to the service manual's troubleshooting guide for detailed information.

Browse all codes in this manual (56)
Verified technical data. Last updated: April 2026

Related Faults

12Alarm 12 - High Pressure Switch S414Alarm 14 - High Pressure Switch S716Alarm 16 - High Pressure Switch S28
Source: Lennox PRODIGY 2.0 Unit Controller
Open Manual (Page 139)Search more codes in this manual