ARCC BU REVIEWER PART 3 (Air-conditioning Systems)

From recorded lecture video (2024)

Comfort

This describes a delicate balance of pleasant feeling in the body produced by its surroundings. A comfortable atmosphere describes our surroundings when we are not aware of discomfort.

Temperature, humidity, air movement, air cleanliness

Comfort involves four things namely-

Conduction, convection, radiation

Three direct ways the human body gives off heat

Evaporation of perspiration

Fourth way the human body gives off heat

Air-conditioning system

A mechanical installation system providing warmed, cooled, clean and otherwise treated air into the habitable spaces of a building

(1) compressor, (2) condenser , (3) refrigerant , (4) evaporator

The four major components of refrigeration

Condenser

Part of an air conditioner where it rejects heat from the system absorbed and is usually placed at the exterior part of a building

Evaporator

The part of an air conditioner in which refrigerant is vaporized, thereby taking up external heat and producing cooling

Duct-free type

A type of air-conditioning system that lacks ducts that convey conditioned air

Ducted type

A type of air-conditioning system that uses ducts that convey conditioned air

Window type system

A duct-free type of air-conditioning that combines the evaporator and condenser into a single unit; demands an opening on a wall, high-amp power outlet, and drain pipe; preferred by developers due to lack of need to accommodate ducts in the ceiling that would otherwise raise the floor-to-floor height of a structure

Split-type system

A duct-free type of air-conditioning that separates the evaporator and condenser units

Air cooled condensing unit (ACCU)

Condenser equivalent in a split-type air-conditioning setup that is located outside of the building

Fan coil unit (FCU)

Evaporator equivalent in a split-type air-conditioning setup that is located inside of the building

1:1

Ratio for ACCU and FCU in a common split-type air conditioning setup

Copper tubes

These connect the ACCU and FCU in a split-type air conditioning setup

Hi-wall, underceiling, cassette (most popular), slimpacs

Type of FCUs

Hi-wall unit

Common type of FCU, placed on a wall

Underceiling unit

Type of FCU that is installed on the ceiling

Cassette

Most popularly-used FCU; usually flushed in ceiling with four-directional output

Slimpac

Type of FCU that is used in banks and commercial buildings, with advantages include direct cooling to occupants, and disadvantages include added floor space and dedicated circulation

Multi-split system

A split-type air conditioning setup where the usual 1:1 ratio of ACCU and FCU can be deviated, with one ACCU equivalent to multiple FCUs.

150 m

Maximum copper pipe length between an ACCU and FCUs in a multi-split air conditioning system

50 m

Maximum height difference between the ACCU and an FCU in a multi-split system on multistory buildings

Air-cooled system

Type of ACCU in a multi-split system characterized by grills that take in air from the outside, while expelling warm air in another outlet; usually placed outdoors

Water-cooled system

Type of ACCU in a multi-split system characterized by the use of water to cool it down; can be placed indoors

Chiller

A component/room in a ducted air conditioning system that produces chilled water from a source; usually placed in the first basement that requires a 3.66 meter (below 20 floors or moderate-sized building) or 4.88 meter (above 20 floors or large-sized building) floor-to-floor height

Air-handling unit (AHU)

A component/room in a ducted air conditioning system that should be provided in every floor of a multistory building

Cooling tower

A component/room in a ducted air conditioning system that is located in the topmost floor of a multistory

3.20 meters

Minimum allowable floor-to-floor height to accommodate a ducted air conditioning system in a multistory building

Willis Carrier

Pioneered the modern type of air conditioning

Elisha Otis

Invented the first ever elevator

(1) Evaporator, (2) Compressor, (3) Condenser, (4) Expansion Chamber

Order of the refrigerant cycle