Lennox Ducted Heating

Lennox Error Code E349

Ducted Heating

E349 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: No 24 Volts between R & O with non-communicating outdoor unit (Dual fuel module required for heat pump application).
  • SL297UHNV: No 24 Volts between R & O on ”integrated control” with non communicating outdoor unit (Dual fuel module required for heat pump application

Causes & actions from Lennox

No 24 Volts between R & O with non-communicating outdoor unit (Dual fuel module required for heat pump application).

Models: SLP98UHV, SLP99UHV

How it shows
  • Integrated control 7-segment display: E349

Configuration link R to O needs to be cut on control board.

Other manual wording

SLP99UHV

Only applicable in non-communicating mode. The O to R link on the furnace has been cut and could possibly cause a brown out. Might also result in low voltage to which would generate alert code as well. Configuration link R to O needs to be restored. Will need to restore link by hard-wiring the R to O terminals on the terminal strip.

Applicable models & manual sources
  • SLP98UHV

    No 24 Volts between R & O with non−communicating outdoor unit (Dual fuel module required for heat pump application).

    SLP98UHV manual, page 64

  • SLP99UHV

    No 24 Volts between R & O with non- communicating outdoor unit (Dual fuel module required for heat pump application).

    SLP99UHV manual, page 32

No 24 Volts between R & O on ”integrated control” with non communicating outdoor unit (Dual fuel module required for heat pump application

Models: SL297UHNV

How it shows
  • Integrated control 7-segment display: E349

Configuration link R to O needs to be restored. Replace link or hard- wire. Applicable in non communicating mode. Critical Alert.

Applicable models & manual sources
  • SL297UHNV

    No 24 Volts between R & O on ”integrated control” with non communicating outdoor unit (Dual fuel module required for heat pump application

    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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