d2 Low

Ferroli d2 Fault Code

Also written as D2 — same fault.

The Ferroli d2 fault code means: your boiler is currently taking a short, scheduled pause to protect itself after being used, and it will automatically start working again once the internal cooldown period is over.. It appears on 2 Ferroli models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Standby or delay time message during heating demand

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ferroli models that show the d2 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli d2 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026