Low
n1 on Protherm 100EC

Your boiler is currently operating in its base 10kW heating mode, which is a standard status indicator rather than a fault, meaning the appliance is functioning correctly.

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

10 kW (34 120 Btu/hr)

From this model's manual
Verified against the Protherm 100ec installation & service manual, page 22.
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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