What does the Vaillant F.83 fault code mean?

Your boiler is failing to detect a change in temperature when it tries to fire up, which usually means there is either not enough water circulating inside the system or a sensor isn't reading correctly.

How much does it cost to fix Vaillant error code F.83?

Typical repair cost for the Vaillant F.83 fault is £120-250 including labour.

Vaillant F.83 Fault Code: What It Means & How to Fix It

Technical description

Fault:NTCtemp.gradient Whentheburnerstarts,thetemperaturechangeregisteredattheflow and/orreturntemperaturesensorisnon-existentortoosmall. – Insufficientwaterinproduct – Floworreturntemperaturesensornotincorrectpositionatpipe

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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Related fault codes

F.22View →F.75View →

Your boiler is failing to detect a change in temperature when it tries to fire up, which usually means there is either not enough water circulating inside the system or a sensor isn't reading correctly.

Technical description

Engineer required

Related fault codes

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