Chiller

The chiller contains the primary cooling medium (refrigerant) which removes heat from a secondary medium (such as water) through cycles of compression and evaporation. The secondary medium then cools the air by passing through coils in other units around the building. Chillers are cooled by fan-driven external air, or by water circulating through a cooling tower.

Air Handling Unit (AHU)

In a ducted system, the central AHU contains the heating and cooling elements, blower, filters, humidifier, dampers and other regulating equipment. On a roof, it’s called an RTU (rooftop unit).

Fan Coil Unit (FCU)

An FCU is a small indoor terminal unit (TU) that controls the temperature in a single room. FCUs contain only a fan, valve and cooling coil linked to a chilled water supply. They may be freestanding or mounted on walls or ceilings.

Split System

A split system uses an outdoor condenser and an indoor terminal unit. They avoid the need for ductwork. In a multi-split system, a single outdoor condenser links to multiple indoor units in different rooms or apartments.

Ducting Installation

Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air. Ducts commonly also deliver ventilation air as part of the supply air.