High
neon flashing (Section M) on Potterton Performa System HE

Your boiler has automatically turned itself off because it has become too hot to operate safely.

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

Flue overheat thermostat operated

From this model's manual
Verified against the Potterton/Potterton Performa System He System installation & service manual.
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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Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like neon flashing (Section M): no call-out fees, no surprise bills.

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All 24 fault codes on the Performa System HE

Seeing a different code? Every code this model can display, in one place.

1011122021232425Flashing Mains ON lightMAINS LED FLASHINGMAINS LED OFFneon flashingneon flashing (Section B)neon flashing (Section C)neon flashing (Section E)neon flashing (Section H & K)neon flashing (Section I)neon flashing (Section J)neon illuminatedneons flashing (Section D)Overheat Stat neons flashingPressure of 3 or greaterReset neon does not extinguish

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