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Lennox · Furnace

E312 Restricted airflow in cooling/fan

Medium severity EL296UHVLennox SL280UHVLennox SL297NV

What the control is telling you

Warning only: blower is in cutback mode, running below the CFM setting because static is outside 0 to 0.8 in. w.c. total external static.

Applies to: EL296UHV(X) series furnaces (integrated control 103130-XX and 107045-XX)

Likely causes

  • Dirty filter
  • Restricted ductwork

Test and repair steps

  1. Measure total external static pressure; design range is 0 to 0.8 in. w.c.
  2. Replace the filter if dirty.
  3. Repair or add duct as needed.
  4. Clears after the current demand is satisfied.

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Source: Lennox EL296UHV(X) Unit Information / Service Literature, Table 5 Ignition Control 103130-XX Diagnostic Codes, p.37; Ignition Control 107045-XX Diagnostic Codes table, p.44. Summarized in our own words; check the original manual for your model.

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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.