High
n8 on Protherm 100EC

The boiler's temperature sensors have detected an issue with the water flow or heat exchange, causing the system to stop working to prevent internal damage.

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

26 kW (88 712 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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