Technical data

Plant Room Siting
Provided certain criteria are met it is possible
to install VRC (centrifugal fans) within a plant
room heaters installed in plant rooms should
only be configured for use in room sealed
mode and provision should be made for the
positive connection of flues , combustion air
pipes, warm air discharge and return
ductwork where such a siting is a
requirement it is recommended that you
consult Benson Technical prior to installation
Additionally the maximum temperature within
the plant room should not exceed 32
0
C
2.0 Installation
The location chosen for the heater must
allow for the fitting of an effective flue
system.
The location must also allow for adequate
clearance for the air supply, return air
circulation, gas supply, electrical supply,
whilst also providing good and safe working
access.
The heater must be installed so that it is
level, supports for the heater must be
sufficiently robust to withstand the weight of
the heater and any ancillary equipment
Any combustible material adjacent to the
heater or flue system must be so placed or
shielded so that its surface temperature does
not exceed 65
0
C. Generally a free blowing
heater should be located at a height
(measured from floor level to the base of
unit) as detailed within section 2.1
VRA free blowing heaters are at their most
effective when located as close to the
working area as possible. However care
should be exercised to avoid directing the
discharged air directly onto the occupants of
the area to be heated.
Where the passage of cold air causes
problems (e.g. by entrances, loading bays
etc) it is considered favourable if the heater
is positioned so as the discharge towards or
across the cold air source from a distance
from 1.5m - 6m dependent upon the size of
the entrance and the air throw characteristics
of the heater. On exposed walls heaters
should be positioned so as to discharge
towards, or along the length of the exposed
wall.
In areas where it is proposed that more than
one heater is to be installed, a general
scheme of circulation should be drawn up
and maintained, thereby offering the best
heat distribution. Air pressure within the area
heated and the outside air pressure must
remain the same, factors influencing this
would be the presence of extraction systems,
ventilation systems, and various types of
process plant.
VRA heaters are only suitable for free
blowing applications or where the duct length
does not exceed 2 metres.
In which case the cross- section of the duct
must be at least the same as that of the
heater discharge grille
VRE heaters configured for down flow
applications should be suspended centrally
over the area into which the warm air is to be
discharged .
2.1 Installation Mounting Heights and
Clearances
The Heater must be installed within the
mounting heights indicated below
The following heights in metres
c) On a level non-combustible surface
Model
VRA/C
40 70 100 135 170
Min 1.8 1.8 2.0 2.0 2.4
Max 2.5 2.5 3.2 3.2 4.0
Model
VRA/C
200 250 330 410 490
Min 2.4 2.4 2.4 2.4 2.4
Max 4.0 5.0 5.0 5.0 5.0
Model
VRE
40 70 100 135 170
Min 3.5 4.0 4.0 4.0 5.0
Max 4.5 5.5 6.0 7.0 8.0
Model
VRE
200 250 330 410 490
Min 5.0 5.0 6.0 6.0 6.0
Max 12.0 8.0 10.0 12.0 12.0