Low
100 on Main Eco Compact

Your boiler is currently running at its absolute maximum heat output, likely because it is performing a diagnostic test or an initial start-up process.

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

Maximum output mode

From this model's manual
Verified against the Main Eco Compact installation & service manual, page 50.
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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