High
A7 on Viessmann Vitodens 242-F B2UA

The control panel that manages your boiler's settings is having a communication error, meaning your heating and hot water controls will likely not work until it is reset or repaired.

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

Programming unit faulty

From this model's manual
Verified against the Viessmann Vitodens 242 F B2ua installation & service manual, page 128.
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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Related fault codes

A8View →A9View →

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