ACiQ error codes, decoded.
Look up any ACiQ fault code below. Each one is grounded in ACiQ's own service documentation — the meaning, the symptoms, the causes, and the steps to clear it.
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ACiQ sits in our HVAC coverage. Every page here is transcribed from the manufacturer's manuals, not scraped from forums.
What error codes does ACiQ display?
Tap a code for the full breakdown — meaning, symptoms, causes, and fix steps.
Indoor and outdoor unit communication error
EL0CSystem lacks refrigerant
EH00Indoor unit EEPROM malfunction / parameter error
EH02Zero-crossing signal detection error
EH03Indoor unit fan speed out of control
EH60Indoor unit room temperature sensor (T1) error
EH61Indoor unit pipe temperature sensor (T2) error
EC51Outdoor unit EEPROM parameter error
EC52Outdoor unit coil temperature sensor (T3) error
EC53Outdoor unit ambient temperature sensor (T4) error
EC54Compressor discharge temperature sensor (TP) error
EC07Outdoor unit fan speed out of control
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