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2 flashes: HPS open ≥6 s; 3: discharge >263°F; 4: discharge <90°F after 1 h; 5: defrost failure; 6: discharge sensor short; 7: outdoor sensor open/short; 9: bonnet sensor fail

What is going on

Possible causes and checks for: 2 flashes: hps open ≥6 s; 3: discharge >263°f; 4: discharge <90°f after 1 h; 5: defrost failure; 6: discharge sensor short; 7: outdoor sensor open/short; 9: bonnet sensor fail.

Likely causes

  • See mfr table
  • Generic illustration only

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Source: General HVAC service practice — verify per model. Written in our own words; check the manual for your exact model.

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.