Medium
Shut down on Potterton Envoy Plus

Your central heating system has trapped air inside, causing the pump to struggle and making the boiler shut down as a precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Air passing through the pump (system not correctly vented) indicated by character displayed in flow temperature/settings and character in status/function

From this model's manual
Verified against the Potterton Envoy 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.

DIY fix possible

Turn off the boiler at the electrical spur.Locate the radiator bleed valves in your home, starting with the ones on the highest floor.Use a radiator key to slowly release trapped air from each radiator until water trickles out, ensuring you top up the system pressure via the filling loop afterwards.

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