… air), not electrically heated, incorporating a motor-driven fan or blower, and parts thereof, of iron or steel. …
Explanatory notes
… air), not electrically heated, incorporating a motor‑driven fan or blower, and parts thereof, of iron or steel. … to the air travelling along its outer surface, and a motor‑driven fan or blower. Generally these heaters are furnished … therefore covers air heaters for space heating and for drying various materials (fodder, grain, etc.), and …