Your boiler has temporarily stopped running because an external safety device, such as a condensate pump or a pipe thermostat, has detected a potential issue and sent a signal to shut the burner down.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner off contact has been triggered this could be because of contact thermostat or condensate pump
What causes this fault?
This fault occurs when an safety device outside of the boiler has tripped and told the system to shut down for protection. The most common reason is a blocked condensate pump that is full of water and cannot drain, or a pipe thermostat that has detected the system is getting too hot and has cut the power to the burner as a precaution.
This fault is more frequent during very cold winter spells, as frozen external drainage pipes can cause condensate pumps to backup and trigger the safety switch.
DIY fix possible
Check if your external condensate pump is plugged in and turned on.Inspect the condensate pump reservoir; if it is full, the pump may be blocked or broken.If you have underfloor heating, check if the limit thermostat has tripped and reset it if necessary.
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