Low
20 on Malvern TenTwenty

Your boiler is displaying its maximum heat output setting rather than a fault, meaning the system is currently operating at full power.

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 (68240 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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