Low
d3 on Ferroli Bluehelix Tech RRT

Your boiler is temporarily waiting to restart as part of its normal safety routine to prevent overheating.

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

Safety pause time

Shared across the Bluehelix Tech 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

d4View →

All 64 fault codes on the Bluehelix Tech RRT

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

A01A02A03A05A06A07A08A09A10A11A13A14A23A23 - A24 - A26A24A26A42A54A54 - A55 - A63A55A56A61A62A63A64A68b09d4E04E05F07F08F09F10F11F12F13F14F15F15 - F20 - F21F20F21F34F37F39F40F40 - F47 - F50F41F42F43F47F50F51F51 - F53F53F56F56 - A56F61F61 - A61F66F67F68F68 - A68

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