Lennox Ducted Heating

Lennox Ducted Heating Error Code E404

Ducted Heating

E404 means different things on different Ducted Heating models. Enter your model number to see only your reading, or find your model below.

What It Means

  • SLP98UHV, SLP99UHV: LSOM - Compressor rotor locked.
  • SL297UHNV: LSOM - Compressor rotor locked. Compressor short-cycling. (Running less than 4 minutes).

Causes & actions from Lennox

LSOM - Compressor rotor locked.

Models: SLP98UHV, SLP99UHV

How it shows
  • Integrated control 7-segment display: E404

Compressor short cycling (Running less than 4 min- utes).

Other manual wording

SLP99UHV

Compressor short cycling (Running less than 4 minutes).

Applicable models & manual sources

LSOM - Compressor rotor locked. Compressor short-cycling. (Running less than 4 minutes).

Models: SL297UHNV

How it shows
  • Integrated control 7-segment display: E404

Compressor rotor locked up due to run capacitor short, bearings are seized, excessive liquid refrigerant, etc. Clears the error after 4 consecutive normal run cycles or after power reset.

Applicable models & manual sources
  • SL297UHNV

    LSOM - Compressor rotor locked. Com- pressor short-cycling. (Running less than 4 minutes).

    SL297UHNV manual, page 59

Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.

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