How much does it cost to fix Vaillant error code F.61?

Typical repair cost for the Vaillant F.61 fault is £250-£550 including labour.

F.61 High

Vaillant F.61 Fault Code

Q: What does the Vaillant F.61 fault code mean?

Your boiler has detected an electrical communication problem with the gas valve, which means it cannot safely light the flame to provide heating or hot water.

Also written as F61 — same fault.

The Vaillant F.61 fault code means: your boiler has detected an electrical communication problem with the gas valve, which means it cannot safely light the flame to provide heating or hot water.. It appears on 53 Vaillant models in our database.

Technical description: Electronic fault | Electronics defect

What causes the Vaillant F.61 fault?

This fault occurs when the boiler's main control board loses the ability to send or receive electrical signals to the gas valve. The most common reason is an internal electronic failure within the circuit board itself, though it can also be caused by loose wiring or a faulty solenoid on the gas valve. Because the boiler cannot safely regulate the flow of gas, it shuts down immediately as a safety precaution.

Typical repair cost £250-£550 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Vaillant models that show the F.61 fault code

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

Source

Vaillant F.61 fault code information on this page is sourced and cross-checked against the official Vaillant service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026