CodeRegistry
Brands
  1. Home
  2. Lennox
  3. EL18KSLV Series Outdoor Units
  4. 27
About·Privacy·Terms

CodeRegistry — Your global library for technical solutions.

For your safety: always follow the equipment manufacturer’s official manuals. CodeRegistry is an independent help site and is not affiliated with the brands listed here.

27

Error 27 — Compressor momentary overcurrent (module inverter)

Lennox · EL18KSLV Series Outdoor Units

What does 27 mean?

The compressor module's inverter side has detected a momentary overcurrent in the compressor.

Common Causes

  • Compressor momentary overcurrent detected by compressor module inverter side
  • Compressor drive module hardware fault
  • IPM fault

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check compressor wiring connections.

  2. 2

    Inspect the IPM for faults.

  3. 3

    Monitor compressor current during operation for spikes.

Browse all codes in this manual (43)
Verified technical data. Last updated: April 2026

Related Faults

1Error 1 — EEPROM malfunction or damage10Error 10 — Outdoor defrost sensor failure11Error 11 — Suction temperature sensor failure
Source: Lennox EL18KSLV Series Outdoor Units
Open Manual (Page 66)Search more codes in this manual