Low
d2 on Ferroli Bluehelix Pro RRT

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Standby or delay time message during heating demand

Shared across the PRO RRT range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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Related fault codes

d3View →

All 54 fault codes on the Bluehelix Pro RRT

Seeing a different code? Every code this model can display, in one place.

A01A02A05A06A07A08A09A10A11A13A14A23A24A26A42A54A55A56A61A62A63A64A68d3d4F07F08F09F10F11F12F13F14F15F20F21F34F37F39F40F41F42F43F47F50F51F53F56F61F66F67F68FH

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