NVX Range Users, Instructions & Service Instructions Issue 5.5 August 2015 Page 9
1.2.7 Air Distribution System
Where NVx/F units are required to cover a large floor
area, and in buildings with high roof or ceiling heights
Calecon thermal economiser units may be considered to
ensure even heat distribution and minimise stratification.
Care should be taken to avoid impeding the air throw with
racking, partitions, plant or machinery etc. Various outlet
configurations are available as optional extras to modify
the air throw pattern to suit particular site conditions.
For ducted units, the duct work must comply to current
regulations and be correctly calculated to match the
particular heaters resistance and air flow.
A full and unobstructed return air path to the air heater(s)
must be provided.
If the air heater(s) is installed in a plant room, the return air
intake(s) and the warm air outlet(s) from the heater(s)
must be fully ducted, into and out of the plant room to
avoid interference with the operation of the heater.
The openings in the structure of the plant room/enclosure
through which the ducting passes must be fire stopped.
Care must be taken to ensure that return-air intakes are
kept clear of sources of smells and fumes, and where
there is any possibility of pollution of the air by dust, shav-
ings etc., precautions must be taken to prevent contami-
nation.
If necessary, suitable barrier rails should be provided to
prevent any combustible material being placed within
900mm of the outlets.
Ducting Requirements
Model
Air Volume m
3
/h
Maximum Duct Resistance
NVx10
936
140
NVx15
1405 145
NVx20
1873 177
NVx25
2341 143
NVx30
2809 250
NVx35
3600 210
NVx40
3746 236
NVx50
4682 205
NVx60
5619 250
NVx75
7024 260
NVx90
8428 200
NVx120
11237 284
NVx140
13110 285