d.94 Low

Heatline d.94 Fault Code

Also written as D94 — same fault.

The Heatline d.94 fault code means: your boiler is prompting you to clear its internal memory or reset a previous fault notification so it can attempt to start up again normally.. It appears on 7 Heatline 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: Reset the fault codes

DIY fix possible

Locate the reset button or dial on the front of your Heatline Monza boiler.Press and hold the reset button for 3 to 5 seconds.Wait a few moments to see if the display clears and the boiler ignites.

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Heatline models that show the d.94 fault code

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

Source

Heatline d.94 fault code information on this page is sourced and cross-checked against the official Heatline service / installation manuals for each affected model.

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