High
06 on Vokera Syntesi 25E / 29E

Your boiler is struggling to detect the temperature of your hot water, which likely means you will have no hot water available until it is fixed.

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 06 appears if a problem exists with the secondary (DHW) thermistor.

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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