Is the GB162 flue system suitable to be ran externally?

The standard 80/125 and 100/150 flue system, which is supplied for use with the GB162 boiler range, is not suitable for external flue runs.  This of course does not affect the protruding parts of the horizontal and vertical terminals.

The flue system has not been classified for external use due to concerns about water ingress into the air duct. Alternatively it is permissible to enclose the flue system externally within a water proof boxing, providing there is access for inspection.