What It Means
- 3.1 - Unit operates with a cooling or continuous fan demand. - Combustion air blower will not start with a Heating demand. - Diaggnostic ligghts flash the limit failure modde. LED#1-Slow Flash, LED#2-On
Lennox Ducted Heating
Lennox Error Code LED#1-Slow Flash, LED#2-On
Ducted Heating:
Causes & actions from Lennox
How it shows
- SureLight board LEDs (DS1/DS2): LED#1-Slow Flash, LED#2-On (led1: flashing (slow), led2: on)
Possible cause: 3.1.1 Primary or secondary (if equipped) limit open. Corresponding action/comments: ACTION 1 − Check continuity across switch(es). Switches reset automatically upon cool down. ACTION 2 − Check for restrictions on blower inlet air (including filter) and outlet air. Determine cause for limit activation before placing unit back in operation. Possible cause: 3.1.2 Miswiring of furnace or improper con- nections at limit switch(es). Corresponding action/comments: ACTION 1 − Check for correct wiring and loose connections. Correct wiring and/or replace any loose connections.
Applicable models & manual sources
- G24M
3.1 − Unit operates with a cooling or con- tinuous fan demand. − Combustion air blower will not start with a Heating demand. − Diaggnostic ligghts flash the limit failure modde. LED#1−Slow Flash, LED#2−On
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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