COOLING THE ROOM

Water-based Indoor Climate Systems, 2007
www.swegon.com

COOLING THE ROOM

COOLING ROOMS

COOLING ROOMS

The room can be cooled in a number of different ways. Below we describe how chilled beams, cooling panels, comfort modules, fan coil units and induction units operate in general and what characterizes each system.

Chilled beams

A chilled beam primarily gives off its cooling effect through convection, i.e. circulating indoor air that flows through the cooling battery, see Figure 25.

The chilled beam can also be combined with a supply air connection to simultaneously work as a supply air device and in many cases, due to the induction effect, increase the cooling effect in the beam, see the section Induction units. At Swegon, we call units of this type: ”active” climate beams because the function can be utilized both for the cooling and heating of premises.
The chilled beam's cooling is usually regulated by a control valve, which sometimes controls several chilled beams depending on the required cooling capacity and flexibility.

Chilled beams work according to the principle “dry” cooling (above the dew point). The cooling medium’s supply temperature should always be higher than the dew point temperature for the air in the room, see the section Condensation protection.

Characteristic of active climate beams

Cost efficient solution with supply air and room cooling in the same unit
Relatively high cooling effect
Important that the supply air is dehumidified so that condensation and thus reduced capacity are avoided
Can also be used for heating as an alternative to radiators

Cooling panels

A horizontal under tempered area that is suspended from the ceiling is called a cooling panel, see Figure 26. Cold water passes through a pipe connected to an aluminium sheet in the cooling panel. Heat is transported from the sheet to the cold water. Cooling panels then cool the warm room air as well as absorb heat from the room through low temperature radiation. These can be surface mounted against the ceiling, individually suspended or integrated in the suspended ceiling. They essentially work as a radiant cooler.

The cooling power of the cooling panels is usually on/off-controlled by a control valve that, among others, controls several cooling panels depending on the cooling capacity and degree of flexibility desired.

Cooling panels work according to the principle “dry” cooling (above the dew point). The cooling medium’s supply temperature should always be higher than the dew point temperature for the air in the room, see the section Condensation protection below.

Typical properties of cooling panels

Discreet solution
Provides cooling in the form of radiation
The cooling effect is limited to approximately 100 W/m² of the active area.

Figure 25.Principle of the chilled beam.

Figure 26.Principle of the cooling panel.

Fan coil units

A unit via which both heating and cooling are delivered to the room (however, not simultaneously). An outline diagram is shown in Figure 27. A fan coil unit is equipped with a fan that circulates room air through the unit. The air is heated or cooling inside the unit in a combined heating and cooling coil with two separate liquid circuits. Hot or chilled water is supplied to the coil from a central unit in the building. Of all the room cooling units, fan coil units have the greatest cooling capacity, but they also generate the highest noise level.
Typical properties of fan coil units

Large cooling effect
Can handle latent cooling if a drainage system is fitted
Relatively high noise levels (at high output)
High operating and maintenance costs (for changing the filter and fan, cleaning the drainage system, for instance)

Induction units

A unit via which both heating and cooling is delivered to the room (however, not simultaneously). An outline diagram of an induction unit is shown in Figure 28.

When an induction unit is used, the ventilation air is supplied to the room via the induction unit. The ventilation air flows with high velocity through a nozzle which causes room air to be entrained by the supply air through a combined heating and cooling coil with two separate water circuits. In this way it is possible to heat or cool the room using one and the same unit without having to use a fan.
Typical properties of induction units

Relatively high cooling outputs
Contains a function for supply air
Important that the supply air is dehumidified so that condensation and thus reduced capacities are avoided
Low operating and maintenance costs

Comfort modules

The comfort module is a completely new type of product that that can be described as a hybrid between a climate beam, a supply air diffuser and a radiator. A comfort module combines the high cooling power of a climate beam when primary air is discharged at low velocity with the supply air diffuser’s capacity for quickly mixing the chilled air with room air. This creates opportunities for generating great cooling power with a considerably smaller unit than with a climate beam. The same function creates better conditions for heating the premises from the ceiling. A diagrammatic illustration of a comfort module is shown in Figure 29. Characteristic of comfort modules

Small overall dimensions enable more free space for other installations in the ceiling
Four-way air distribution enables a larger mixing zone and a high standard of comfort
Tempers and ventilates rooms for a high standard of comfort whatever time of year (ventilation, cooling and heating)
No moving parts, this means low maintenance costs
Immense flexibility throughout its useful life

Figure 27.Principle of the fan coil units.

Figure 28.Principle of the induction units.

Figure 29. Principle of a comfort module.