Lennox Packaged Unit

Lennox Error Code Blinking

Packaged Unit: Packaged HVAC (outdoor)

What It Means

  • HB LED blinks while M4 is powered.

Causes & actions from Lennox

How it shows
  • core unit heartbeat led: Blinking

Heartbeat LED blinks while M4 is powered

Other manual wording (1 of 2)

LCT156H, LCT180H, LCT210H, LCT240H, LCT300H, LGT156H, LGT180H, LGT210H, LGT240H, LGT300H

Heartbeat LED (HB LED) blinks while M4 Unit Controller is powered.

Other manual wording (2 of 2)

LHX092, LHX102, LHX120

This manual entry does not list further causes or actions.

Applicable models & manual sources
  • LCM156U

    HB LED blinks while M4 is powered.

    LCM156U, LCM180U, LCM210U, LCM240U, LCM300U, LGM/LCM156U, LGM/LCM180U, LGM/LCM210U, LGM/LCM240U, LGM/LCM300U, LGM156U, LGM180U, LGM210U, LGM240U, LGM300U

    LCM156U manual, page 17

  • LGX092

    HB LED blinks while M4 is powered.

    LGX092, LGX102, LGX120, LGX150, LCX092, LCX102, LCX120, LCX150

    LGX092 manual, page 17

  • LGT156H

    HB LED blinks while M4 is powered.

    LGT156H, LGT180H, LGT210H, LGT240H, LGT300H, LCT156H, LCT180H, LCT210H, LCT240H, LCT300H

    LGT156H manual, page 19

  • LHX092

    HB LED blinks while M4 is powered.

    LHX092, LHX102, LHX120

    LHX092 manual, page 14

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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