Mech/Elec ALS Lesson Three - Mechanical Equipment and Energy Codes: Plant Types - Boilers and Chillers

Topic:

Plant types - Boilers and Chillers

GENERAL

Heating, Ventilating and Air Conditioning (HVAC) mechanical equipment is used to supplement and control a buildings thermal loads.

Two basic elements:

Plant = Creates the warm or cool water or air, usually in a central equipment room or location

Distribution = mechanism or system which delivers the heated or cooled air or water to the necessary zones or rooms in a building.

PLANT TYPES - BOILERS AND CHILLERS

Early plants = for heating only by hot water or steam

Air conditioning = when developed, plants became sources of chilled water or cooled air also

Heated water  = Fire under a tank or heat exchanger tub, called a boiler

Exhaust flue = required to vent combustion byproducts

external combustion air = brought in from outside instead of wasting warmed interior air for the process

forced air furnace = compact version of boiler, air is moved through a manifold warmed by burning Oil, Natural gas or propane. 

Gravity feed = furnace in basement and hot air would rise into house above, air moved too slow

Fan = introduced to place furnace anywhere, like attic, requires return air and ducts

Downdraft furnace = air flow is downward through the furnace reversing the convection

lowboy = a furnace that is reduced to five feet high allowing a more compact location