Lennox Ducted Heating

Lennox Ducted Heating Error Code E120

Ducted Heating

E120 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

  • SL280DFNV, SL280UHV, SL297UHNV: Unresponsive device. Communication only.
  • SLP98UHV, SLP99UHV: Unresponsive device.

Causes & actions from Lennox

Unresponsive device. Communication only.

Models: SL280DFNV, SL280UHV, SL297UHNV

How it shows
  • Integrated control 7-segment display: E120

Usually caused by delay in outdoor unit responding to indoor unit poling. Recycle power. Check all wiring connections. Cleared after unresponsive device responds to any inquiry.

Applicable models & manual sources

Unresponsive device.

Models: SLP98UHV, SLP99UHV

How it shows
  • Integrated control 7-segment display: E120

Usually caused by delay in outdoor unit responding to indoor unit poling recycle power, check wiring.

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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