High
A.(6) on Potterton Kingfisher 2 RS60, RS80, RS100

Your boiler is unable to start its pilot flame or has shut down to prevent the system from getting too hot.

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

Pilot fails to light - Overheat thermostat not operating.

Shared across the Kingfisher 2 range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal safety sensors detect that the unit has become dangerously hot or when the pilot light fails to stay lit. The most common reason is a failing thermocouple that can no longer sense the flame, or a tripped overheat thermostat caused by a circulation issue like a pump failure.

This issue is more common during the first cold spell of autumn, as pump blockages or airlocks often occur after the heating has been switched off all summer.

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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Avoid the next call-out bill

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Related fault codes

All 17 fault codes on the Kingfisher 2 RS60, RS80, RS100

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

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