Flueway | Article about flueway by The Free Dictionary
The clear space (free open area) for the passage of flue gases within a chimney.
References in periodicals archive
"All chimneys and flueways
should be cleaned and checked during the summer months to ensure they're free from debris and in full working order before the heating season.
The engineer will need to do a bit more than check the colour of the burners and clean the boiler flueways
during the annual service.
Accessibility To Flueways
From Both Ends For Inspection And Cleaning Without Removing Entire Jacket