Low
83 on Vokera Syntesi 25

Your boiler is experiencing a communication error between its internal parts, which it is currently trying to resolve automatically.

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

Temporary fault code (Refer to section 7.10)

From this model's manual
Verified against the Vokera Linea He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal components struggle to send electrical signals to each other reliably. It is often caused by atmospheric moisture affecting the circuit board or loose connections within the internal wiring loom that disrupt the flow of data. While the boiler attempts to fix this itself, it usually indicates that the electronic 'brain' is starting to fail or has a poor connection.

This issue can be more frequent in autumn and winter when increased humidity or dampness in the air can interfere with sensitive electrical connections and circuit boards.

DIY fix possible

Wait up to 15 minutes for the boiler to self-correctTurn the selector switch to the 'Reset' position, wait for two seconds, and turn it back to the 'On' positionCheck if the boiler pressure is between 1 and 1.5 bar on the gauge

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