Lennox Split & Multi-Split

Lennox Error Code E355

Split & Multi-Split

E355 means different things on different Split & Multi-Split models. Enter your model number to see only your reading, or find your model below.

What It Means

  • CBX40UHV: Heat section / Stage 5 failed.
  • CBK48MVT: There is a problem with the air-handler's fifth stage electric heat. Either the pilot relay contacts did not close, or the relay coil in the electric heat section did not energize. The air-handler will operate on first stage electric heat until the issue is resolved.

Causes & actions from Lennox

Heat section / Stage 5 failed.

Models: CBX40UHV

Air handler (indoor)

How it shows
  • Single-character display: E355

This manual entry does not list further causes or actions.

Applicable models & manual sources

There is a problem with the air-handler's fifth stage electric heat. Either the pilot relay contacts did not close, or the relay coil in the electric heat section did not energize. The air-handler will operate on first stage electric heat until the issue is resolved.

Models: CBK48MVT

How it shows
  • Single-character display: E355

Heat section / stage 5 failed (same as code 351). Pilot relay contacts did not close, or the relay coil in the electric heat section did not energize. The air-handler will operate on stage 1 heat only. The alarm clears after stage 2 relay is detected.

Applicable models & manual sources
  • CBK48MVT

    There is a problem with the air-handler's fifth stage electric heat. Either the pilot relay contacts did not close, or the relay coil in the electric heat section did not energize. The air-handler will operate on first stage electric heat until the issue is resolved.

    CBK48MVT manual, page 52

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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