Lennox Ducted Heating

Lennox Error Code DS1 SLOW FLASH, DS2 ON

Ducted Heating:

What It Means

  • Primary or secondary limit switch open. Limit must close within 3 minutes or unit goes into 1-hour Watchguard.

Causes & actions from Lennox

How it shows
  • g51mp surelight ds1 ds2 led: DS1 SLOW FLASH, DS2 ON (ds1: flashing (slow), ds2: on)

This manual entry does not list further causes or actions.

Applicable models & manual sources
  • G51MP

    Primary or secondary limit switch open. Limit must close within 3 minutes or unit goes into 1−hour Watchguard.

    G51MP manual, page 54

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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