Low
AF on Ravenheat White Heat WH 80/90

Your boiler is temporarily heating its own pipes to prevent them from freezing while the weather is extremely cold.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Frost protection device operating

From this model's manual
Verified against the Ravenheat White Heat Wh 80 90 installation & service manual, page 44.
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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