Hearth Dampers are usually not satisfactory in Kitchen Extract systems as they may become unserviceable with exposure to grease and become unachievable to clean. On completion of any RecoAir device set up, the air volume movement charges to extract & return air ductwork needs to be confirmed by a suitably https://fire-resisting-ductwork46778.goabroadblog.com/28528222/detailed-notes-on-kitchen-extract-systems