Daikin · Furnace

EAr A2L relay fault - mitigation mode

High severity Daikin DR96TN/DD96TN

What the control is telling you

The A2L relay on the furnace control board has a fault. The furnace goes into mitigation mode (no gas heat, fan only). The troubleshooting chart prints this code as 'Ear'.

Applies to: Daikin DR96TN (upflow/horizontal) and DD96TN (downflow/horizontal) two-stage 96% furnaces with 9-speed ECM motor, R-32 ready

Likely causes

  • A2L relay fault on the integrated control board

Test and repair steps

  1. Check the A2L relay and its field wiring (ventilation VT IN/VT OUT and A2L alarm outputs).
  2. Cycle power to the furnace.
  3. If the code returns, replace the integrated control board.

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Source: Daikin RSD6612304 (DR96TN/DD96TN service), 2 Stage Troubleshooting Codes, p.28-29; R-32 Information p.10. 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.