Hayward Mini Split Error Codes

8 codes · manual-verified where marked · draft entries clearly flagged

A-codes

• Hayward AO / AC error code draft
  Blower Vacuum Switch Error AO means vacuum switch won't close (no air movement detected). AC means vacuum swit…

B-codes

• Hayward bD / EE / CE error code draft
  Control Board / Communication Errors Control board or display communication errors. Erratic display behavior, …

H-codes

• Hayward HF error code draft
  Flame Present / Gas Valve Off Flame detected when gas valve should be closed—serious safety condition requirin…
• Hayward HS error code draft
  High Temperature / Rapid Rise High return water temperature or rapid temperature rise detected. Heater starts,…

I-codes

• Hayward IF / IO error code draft
  Ignition Failure Ignition failure during startup sequence. Heater clicks, blower runs, but never lights. No ga…

L-codes

• Hayward LO error code draft
  Safety String Open / Low Pressure Safety string open—water pressure switch, limit switch, or vent pressure swi…

P-codes

• Hayward PF error code draft
  Power Fault / Low Voltage Supply voltage polarity reversed or voltage too low. Heater will not fire. Hot and n…

S-codes

• Hayward SF error code draft
  Temperature Sensor Failure Temperature sensor (thermistor) input failure. Temperature reading wildly inaccurat…