Emergency
E78-181 on Potterton Kingfisher MF RSL

Your boiler has detected that dangerous exhaust gases are not escaping correctly through the flue, so it has shut down for your protection.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Products Discharge Safety Device - TTB CFL60 - 100 (Yellow sleeve)

From this model's manual
Verified against the Potterton Kingfisher Mf Rsl 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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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