Boiler locks out occasionally during very cold weather, external condensate pipe is icy

Safety first: Take care on icy ground outside.

User fix:

• Locate the external condensate pipe (usually white or black plastic) and the outlet.
• If frozen, pour warm (not boiling) water along the length of the pipe to thaw it.
• Once thawed, reset the boiler and check operation.
• Consider adding temporary insulation (foam pipe lagging) to the external section.

Professional actions:

• An engineer can reroute or upsize the condensate pipe and insulate it according to Baxi and industry guidance.