Lennox Split & Multi-Split

Lennox Split & Multi-Split Error Code U

Split & Multi-Split: Air handler (indoor)

What It Means

  • Discharge air sensor temperature (indoor blower must be operating) U105

Causes & actions from Lennox

How it shows
  • Single-character display: U

Discharge air sensor temperature (indoor blower must be operating) U 105

Other manual wording

CBK48MVT

This manual entry does not list further causes or actions.

Applicable models & manual sources
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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