High
16 on Malvern TenTwenty

Your boiler has detected an issue with the heat output control system and has shut down to prevent the unit from operating outside of its safe temperature limits.

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

kW (54592 Btu/h)

From this model's manual
Verified against the Malvern Tentwenty installation & service manual, page 11.
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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