This balancing plenum connects grilles to the ductwork, equalises the airflow by reducing the velocity – while air is spread evenly into the grille, thus ensuring proper function. It also has efficient sound attenuation, robust and air-tight construction, and wide range of available sizes.
No special dimensions available.
|Attenuation material||Mineral wool||Alternatively polyester fibre|
|Spigot with gasket||Galvanised steel||Gasket rubber compound|
| Body: Aluminium
Plate: Galvanised steel
Brackets: Galvanised steel
Plastic parts: Polypropylene (PP)
Spindle: Stainless steel
|Airflow measurement and
|MSM||Adjustment and measurement
module for supply airflow rate
|Airflow adjustment unit||MEM||Adjustment module for exhaust airflow rate|
|Sound attenuation||IN||Internal sound attenuation material
of mineral wool or polyester fibre
When using Halton PRL with Halton EVA exhaust unit, the plenum will delivered without telescopic collar (order code: ES=Y)
Fig.1. Halton PRL/A, PRL/D or PRL/G (side connection)
Fig.2. Halton PRL/B, PRL/E or PRL/H (back connection)
Fig.3. Halton PRL/C, PRL/F or PRL/I (top/bottom connection)
Halton PRL balancing plenum equalises the airflow by reducing the flow velocity.
Air is spread evenly into the grille, ensuring proper function.
A range of grilles can be connected to the distribution duct with the aid of a Halton PRL, improving their characteristics considerably.
The plenum also attenuates duct noise.
Halton PRL can also be used as an exhaust unit.
Halton PRL is connected to the duct with a spigot equipped with a gasket. The duct connection can be located on the side, above/below or behind the plenum. Due to the symmetrical structure of the Halton PRL, connections can be made in a number of different ways: by turning the plenum right or left, or by rotating, from above or below.
The telescopic collar of the plenum permits mounting into walls of thickness 90…150 mm.
For installation with Halton EVA exhaust unit no telescopic collar is used (not included to delivery).
The recommended safety distance upstream of the plenum in supply installations is minimum 3D.
Dimensions for installation hole are (H+5mm) x (B+5mm).
The supply flow rate is determined by using the measurement and adjustment module MSM.
The tubes and control spindle are passed through the grille. Measure the differential pressure with a manometer. The flow rate is calculated using the formula below.
∆pm Measured pressure [Pa]
k The k factor given as a function of mounting and diameter
qv Airflow rate [l/s]
|PRL||> 8xD||min. 3xD|
Adjust the airflow rate by rotating the control spindle until the desired setting is achieved.
Lock the damper position with a screw. Replace the tubes and spindle into the plenum.
Detach the grille and the perforated plate of the telescopic collar. Detach the measurement and adjustment module by pulling gently from the casing (not from the control spindle or measurement tubes). Wipe the parts with a damp cloth, instead of immersing in water.
The measurement and adjustment module is remounted by pushing the body until it meets the stopper.
The sound attenuation material within the plenum can also be removed (the material is washable), to enable cleaning of the inner side of the plenum. The material is detached by releasing the retaining brackets, which are replaced after washing.
Replace the grille after cleaning.
The Halton PRL balancing plenum for grilles is made of galvanised steel and has a robust and airtight construction.
Airflow rate measurement and adjustment module are available for supply application. The measurement and adjustment module is adjustable without opening the grille.
The balancing plenum has a spigot with integral gasket for airtight duct connection and a plug for ductwork pressure testing. The Halton PRL plenum has options for duct connection on the side, back or top.
The balancing plenum attenuates duct noise. The sound attenuation material is either mineral wool or polyester fibre with a washable surface.
S = Model
A Supply inlet (Left-Right connection)
B Supply inlet (Back connection)
C Supply inlet (Top/Bottom connection)
D Exhaust outlet (Left-Right connection)
E Exhaust outlet (Back connection)
F Exhaust outlet (Top/Bottom connection)
G No accessories (Left – Right connection)
H No accessories (Back connection)
I No accessories (Top/Bottom) connection
W = Width of grille connection (mm)
200, 300, 400, 500, 600, 800
H = Height of grille connection (mm)
100, 150, 200
D = Connection size of duct (mm)
125, 160, 200, 250, 315
ES = EVA model
AT = Sound attenuation material
P Polyester fibre
W Mineral wool
NA No sound attenuation
OM = Measurement/adjustment modul
YS MSM installed (supply)
YE MEM installed (exhaust)
NA No measurement or adjustment module
ZT = Tailored product
Y Yes (ETO)
PRL/A-200-100-125, ES=N, AT=P, OM=YS, ZT=N