High
d2 on Vokera Syntesi 25E / 29E

Your boiler is struggling to detect that it is safely draining away the water created during its operation, causing it to stop working to prevent internal damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Fault code d2 appears if a problem exists with the condense sensor.

From this model's manual
Verified against the Vokera Syntesi 25e 29e installation & service manual, page 34.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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