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Ariston Alteas Fault Codes

The Ariston Alteas One is the flagship of the UK range — the black-glass-fronted combi with Ariston NET connectivity built in, sitting above the Genus. It speaks the family's three-digit fault language (1xx heating circuit, 5xx ignition and flame, 3xx electronics, 6xx flue, P-codes for anomalies) and adds the connected dimension: faults surface in the Ariston NET app, often with guidance, and Ariston's remote diagnostics can read the boiler's state before anyone visits. The practical playbook: note the code (screen or app), do the homeowner basics where relevant — 108 is a pressure top-up, winter 501s want the condensate pipe checked — and use the warranty, which on a registered Alteas is among the longest in the market. Codes below link to their full diagnosis pages.

Where Alteas fault codes appear

The Alteas One shows codes on its glass fascia display and mirrors them to the Ariston NET app, frequently with a plain-language description. Screenshot the app or photograph the display — code plus description is exactly what support and engineers want.

Resetting a Ariston Alteas

Reset from the fascia or, for many lockouts, remotely via the app; top up to 1–1.5 bar before resetting a 108. The connected route matters on this boiler: Ariston's support can often see what tripped remotely, so calling with the code beats resetting it into silence.

Common Alteas problems

The Alteas is young and premium, so its code list in the wild is short: pressure events, winter condensate-related 501s, and occasional electronics/connectivity quirks resolved by power-cycling or firmware rather than parts. Almost every persistent Alteas fault is a warranty conversation — keep registration and servicing current and have the app installed before you need it.

Most common Alteas fault codes

Last reviewed 25 August 2026.

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