Medium
9E on Viessmann Vitodens 242-F B2UA

Your solar heating system has stopped circulating fluid properly or has become too hot, meaning your solar panels won't help heat your water right now.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

No flow rate in solar circuit, or flow rate too low, or temperature limiter responded

From this model's manual
Verified against the Viessmann Vitodens 242 F B2ua 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.

Engineer required

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

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Related fault codes

9AView →9CView →9FView →F3View →

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