High
n7 on Protherm 100EC

Your boiler's internal computer is struggling to communicate with its control sensors, preventing it from safely starting your heating or hot water.

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

24 kW (81 888 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 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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