Lennox Ducted Heating

Lennox Error Code SIMULTANEOUS SLOW FLASH

Ducted Heating:

What It Means

  • Power on - Normal operation. Also signaled during cooling and continuous fan.

Causes & actions from Lennox

How it shows
  • SureLight board LEDs (DS1/DS2): SIMULTANEOUS SLOW FLASH (led1: flashing (slow), led2: flashing (slow))
  • SureLight board LEDs (DS1/DS2): SIMULTANEOUS SLOW FLASH (led1: flashing (slow), led2: flashing (slow))
  • SureLight board LEDs (DS1/DS2): SIMULTANEOUS SLOW FLASH (led1: flashing (slow), led2: flashing (slow))

This manual entry does not list further causes or actions.

Applicable models & manual sources
  • G43UF

    Power on − Normal operation. Also signaled during cooling and continuous fan.

    G43UF manual, page 11

  • G43UF

    Power on − Normal operation. Also signaled during cooling and continuous fan.

    G43UF manual, page 11

  • G43UF

    Power on − Normal operation. Also signaled during cooling and continuous fan.

    G43UF manual, page 11

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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