Mechanical Code…
- Forced-Air-Type Central Furnace
-
A central furnace equipped with a fan or blower that provides the primary means for circulation of air.
- Horizontal-Type Central Furnace
-
A furnace designed for low-headroom installations with airflow through the appliance in a horizontal path.
- Upflow-Type Central Furnace
-
A furnace designed with airflow essentially in a vertical path, discharging air at or near the top of the furnace.
- Downflow-Type Central Furnace
-
A furnace designed with airflow essentially in a vertical path, discharging air at or near the bottom of the furnace.
- Enclosed Furnace
-
A specific heating or heating and ventilating furnace incorporating an integral total enclosure and using only outside air for combustion.
(Uniform Mechanical Code® 208.0)