What does the Viessmann 63:15 fault code mean?

Your boiler has detected an internal electronic error that suggests the main control unit is beginning to fail, which may cause your heating and hot water to become unreliable.

How much does it cost to fix Viessmann error code 63:15?

Typical repair cost for the Viessmann 63:15 fault is £450-750 including labour.

Viessmann 63:15 Fault Code: What It Means & How to Fix It

Technical description

2x daily

What causes this fault?

This fault occurs when the boiler's internal computer brain fails to perform its routine self-checks correctly. It is typically caused by aging electronic components on the circuit board that can no longer communicate reliably with the rest of the system. While the boiler may occasionally clear the error on its own, it usually indicates that the hardware is worn out and needs professional attention.

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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Your boiler has detected an internal electronic error that suggests the main control unit is beginning to fail, which may cause your heating and hot water to become unreliable.

Technical description

What causes this fault?

Engineer required

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