BoilerFaultCodesAriston A33 Fault Code
The Ariston A33 fault code means: your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning or communicating correctly, causing the system to stop working as a safety precaution.. It appears on 10 Ariston models in our database.
Technical description: Problem with the fan
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Search the official register for a qualified engineer in your area.
Gas Safe Register →Ariston models that show the A33 fault code
Click a model for the full fault code list and model-specific repair notes.
- Challenger 80E Repair: £150-300
- E-Combi One Repair: £150-300
- E-Combi One 30 Repair: £150-300
- Genus 24 MFFI Repair: £180-350
- Genus 27 Repair: £250-£450
- Genus 30 Plus Repair: £180-350
- Genus One 24 Repair: £180-350
- Genus One 30 Repair: £180-350
- Genus Premium Repair: £220-450
- Microsystem 15 Repair: £150-300
Source
Ariston A33 fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026