Low
12 on Malvern TenTwenty

Your boiler is displaying a power output reading rather than a fault, which usually indicates the system is in its start-up configuration mode.

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

kW (40944 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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