DID642

Functional description

Active chilled beams provide centrally conditioned primary air (fresh air) to the room and use heat exchangers for additional cooling and/or heating.

The primary air is discharged through nozzles (five variants are available) into the mixing chambers; as a result of this, secondary air (room air) is induced via the induced air grille and passes through the horizontal heat exchanger, where it is heated or cooled.

Primary and secondary air mix and are then supplied to the room horizontally through the supply air slots.

The quick sizing table contains operating points for defined reference units. In this quick sizing, a primary air connection with D = 123 mm is considered for the nozzles HE and S1. For nozzles S2, HP, DA, DB and DS, a primary air connection with D = 158 mm is considered.

DID642–2–S1–LL/1193×1200×593/123

DID642–D1–4–S2–RR–AV–A1/1798×1200×598/158/123/P1-RAL9006/LE/VS/KV–0.40/HV–0.25/R

Set of air control blades

If a high cooling capacity is required in a very small space with active chilled beams, optional air control blades allow for adjusting the air discharge pattern such that the acceptable air velocity in the occupied zone is not exceeded. The airflow of each active chilled beam is spread and discharged according to the room geometry. If the use of a room changes, the air discharge pattern can be optimised by adjusting the air control blades accordingly.

• It is possible to adjust several air control blades (i.e. a set of air control blades) together
• For fine adjustment, the sets of air control blades can be disconnected from each other
• To adjust a set of air control blades, use both hands to move the two outer blades of the set as required
• Maximum possible adjustment is 45° to the right or left in steps of 15°
• The blades are factory set to straight air discharge

If the air discharge is not straight, the water-side capacity will be slightly affected. The effects can be taken into consideration when the Easy Product Finder is used for sizing.

• L₁ = L_N − 62
• L₂ = (L_N − 62) ∕ 2
• L₃ = L – L_N + 10
• L₄ = L – L_N + 52

Aerodynamic data – extract air

Dimensions [mm]

Dimensions [mm]

B = Width of front frame

Weight

L = Total length (diffuser face)

L_N = Nominal length

① Contained water

Non-active section as extension: 10 kg/m

Differences in weight for the various widths can be neglected

• L₅ = L − 62
• L₆ = (L_N − 74) ∕ 2
• L₇ = (L_N − 64) ∕ 2
• L₈ = (L_N − 60) ∕ 4
• L₉ = (L − L_N + 53) ∕ 2) − 26

Dimensions [mm]

Dimensions [mm]

B = Width of front frame

Weight

L = Total length (diffuser face)

L_N = Nominal length

① Contained water

Non-active section as extension: 10 kg/m

Differences in weight for the various widths can be neglected

Installation and commissioning

• Preferably for rooms with a clear height up to 4.0 m
• Flush ceiling installation
• Lengths from 893 to 3000 mm, and widths of 593, 598, 618 and 623 mm, hence suitable for all ceiling systems, particularly for grid ceilings with grid size 600 or 625
• Side entry primary air spigot
• Active chilled beam has 4 suspension points for on-site installation (by others)
• Installation and connections to be performed by others; fixing, connection and sealing material to be provided by others
• Heat exchangers are fitted with water flow and water return connections at the narrow side

Installation into T-bar ceilings or continuous ceilings

• To avoid too much load on the ceiling, the suspension points should be used

L_N [mm]

Nominal length

L_WA [dB(A)]

Sound power level

t_Pr [°C]

Primary air temperature

t_WV [C°]

Water flow temperature – cooling/heating

t_R [C°]

Room temperature

t_R [C°]

Room temperature

t_AN [C°]

Secondary air intake temperature

Q_Pr [W]

Thermal output – primary air

Q_tot [W]

Thermal output – total

Q_W [W]

Thermal output – water side, cooling/heating

V_Pr [l/s]

Primary air volume flow rate

V_Pr [m³/h]

Primary air volume flow rate

V_W [l/h]

Water flow rate – cooling/heating

V [l/h]

Volume flow rate

∆t_W [K]

Temperature difference – water

∆p_W [kPa]

Pressure drop, water side

∆p_t [Pa]

Total pressure drop, air side

∆t_Pr = t_Pr - t_R [K]

Difference between primary air temperature and room temperature

∆t_RWV = t_WV - t_R [K]

Difference between water flow temperature and room temperature

∆t_Wm-Ref [K]

Difference between mean water temperature and reference temperature

L_N [mm]

Nominal length

Mixed flow

The supply air is discharged from the diffuser into the space with a velocity between 2 and 5 m/s. The resulting air jet mixes with the room air, ventilating the entire space. Mixed flow systems typically provide a uniform temperature distribution and air quality within the space. The originally high velocity of the turbulent air jet decreases rapidly due to the high induction levels of mixed flow systems.

Heat exchanger

The maximum water-side operating pressure for all heat exchangers is 6 bar.

The maximum water flow temperature (heating circuit) for all heat exchangers is 75 °C; if flexible hoses are used, the water flow temperature should not exceed 55 °C. Units for other pressures and temperatures are available on request.

The water flow temperature (cooling circuit) should be at least 16 °C such that it does not permanently fall below the dew point. For units with a condensate drip tray the water flow temperature may be reduced to 15 °C.

Heat exchanger as 2-pipe system

Air-water systems with a 2-pipe heat exchanger may be used for either heating or cooling. In changeover mode it is possible to use all units within a water circuit exclusively for cooling in summer and exclusively for heating in winter.

Heat exchanger as 4-pipe system

Air-water systems with a 4-pipe heat exchanger may be used for both heating and cooling. Depending on the season, i.e. especially in spring and autumn, it may be possible that an office has to be heated in the morning and cooled in the afternoon.