The " AIREXTUBE " air make-up system can be used in all applications
where the replacement of exhausted air is required due to general
ventilation or local extraction. Without this air replacement the
building is maintained under negative pressure, reducing the efficiency
of exhaust fan and increasing infiltrations and draughts which make the
work areas uncomfortable.
The "AIREXTUBE" systems, available in five sizes and four different
models, include one housing, one (or more) motorized dampers, one axial
fan and motor, and one flexible fire retardant polyethylene fabric
perforated duct.
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Theory of operation
The operation of the AIREXTUBE is very simple and consists in
using the hot air stratified at the top of the building to
preheat the cold air introduced before it reaches the work area.
The result is a very uniform temperature from bottom to top of
the building. Because the top layer of warm air is usually not
utilized, the make-up air can then be considered as "free air".
This represents an important advantage over the conventional gas
or electric make-up units; the initial cost of an "AIREXTUBE" as
well as its operation cost are much lower. |
| Advantages
The AIREXTUBE is available in four different configurations
allowing a wide variety of uses. This versatility permits the
AIREXTUBE to cover every need of the industry.
Single compensation system (CS)
This unit has one motorized back-draught damper at the rear of
the casing (damper X) that closes automatically when the unit
stops operating to avoid any air infiltration. The fan and
damper are operated by an on-off remote control if needed. This
control can be easily interlocked with the evacuation fan
controls.
Compensation and mixing system (CM)
The CM unit is similar to the CS, except for a mixing damper
(damper Y) on top of the casing. This second damper, controlled
by a thermostat placed in the ducting, pre-mixes the air in the
housing during cold weather. As in the CS model, the unit is
supplied with an "on-off" switch.
Recirculating systems (RS)
This model has a different function than the two others. It is
used where air compensation is not required (ex. warehouses),
but where the cost of heating can be lowered by using the
stratification in top part of the building. The unit is provided
with an opening (Z) at the bottom part of the housing. A
recirculating duct must be used to bring the air from the floor
level to the "Airextube". The unit is supplied with a "on-off"
switch.
Combined system (CR)
This model is provided with a damper (X) at the back and a
damper (z) at the bottom of the casing. The unit has two
functions : during the day, when the exhaust fans are working,
it will act as an air compensation unit (CS); during the night
and week ends, it functions as an air recirculation unit (RS).
The unit is supplied with a three position remote control
(compensation - off-recirculation). |
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Options & Accessories
Weather hood (model CS, CM, CR)
Placed outside the building, it prevents water and snow from entering
the unit. It is supplied with a birdscreen; it can be provided with a
mosquito net as an option.
Recirculating duct (model RS, CR)
A recirculating duct of variable length, provided with a screen at the
inlet can be ordered.
Emergency thermostat (model CS, CM, CR)
A protection thermostat in the control box is available as an option.
This thermostat stops the unit if the room temperature reaches 7°C or
less. It is used for protection in case of heating system break-down
during week ends and holidays. |
