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Ariston fault-code guides
Source-backed fault-code guidance for the verified Clas ONE range.
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Enter the code as it appears on your Ariston boiler display. We show published, verified entries for the matching range.
Source-backed catalogue
Verified boiler fault-code guides
Choose a supported model and code to read the catalogue entry and its source documents.
Ariston · Clas ONE
- Ariston 205DHW inlet probe open circuit (solar temperature probe).
- Ariston 3P9Scheduled maintenance - call service.
- Ariston 411Room sensor circuit open or short circuit, zone 1.
- Ariston 412Room sensor circuit open or short circuit, zone 2.
- Ariston 413Room sensor circuit open or short circuit, zone 3.
- Ariston 701Zone 1 send sensor defective.
- Ariston 702Zone 2 send sensor defective.
- Ariston 703Zone 3 send sensor defective.
- Ariston 711Zone 1 return sensor defective.
- Ariston 712Zone 2 return sensor defective.
- Ariston 713Zone 3 return sensor defective.
- Ariston 108108 indicates insufficient water pressure.
- Ariston 501501 indicates that no flame was detected.
- Ariston 103Insufficient circulation.
- Ariston 104Insufficient circulation.
- Ariston 105Insufficient circulation.
- Ariston 106Insufficient circulation.
- Ariston 107Insufficient circulation.
- Ariston 109System pressure greater than 3 bar.
- Ariston 110Central-heating flow temperature probe circuit open or short circuit.
- Ariston 112Central-heating return temperature probe circuit open or short circuit.
- Ariston 114External sensor circuit open or short circuit.
- Ariston 116Floor thermostat contact open.
- Ariston 118Heating delivery probe problem.
- Ariston 1P1Insufficient circulation indication.
- Ariston 1P2Insufficient circulation indication.
- Ariston 1P3Insufficient circulation indication.
- Ariston 1P4Insufficient circulation indication.
- Ariston 301EEPROM error.
- Ariston 302Communication error.
- Ariston 303Main PCB error.
- Ariston 304Too many (>5) resets in 15 minutes.
- Ariston 305Main PCB error.
- Ariston 306Main PCB error.
- Ariston 307Main PCB error.
- Ariston 5P1First ignition attempt failed.
- Ariston 5P2Second ignition attempt failed.
- Ariston 5P3Flame cut-off.