(a) "Mechanical warm air heating systems" means one or more warm air heating units, one or more motor driven blowers, smoke or vent pipes, individual leader pipes or trunk line systems, or both, with necessary control dampers for supply and return air, automatic controls, registers, faces and grilles, humidifiers, and with provision for other appurtenances such as filters, air washers, ozonators, etc., as may be desired.
(b) "Individual supply system" means separate ducts of round or rectangular cross-sections without branches and extending from the heating unit. Return ducts, trunk lines or a combination of both may be individually installed.
(c) "Trunk line system" means one or more main ducts with branches.
(Ord. 421-47. Passed 4-7-47.)