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5 - FRESH AIR
5.1 - Constant flow fresh air controller
The 42BJ ICM can be fitted with a constant fresh air flow
controller allowing the number of air changes to be controlled.
It is vital to choose the correct constant fresh air flow
controller for the use to which the room or zone concerned
will be put.
The following range of controllers is available:
- 8.3 l/s or 30 m
3
/h (-10% ; +20%)
- 16.6 l/s or 60 m
3
/h (-10% ; +20%)
The fresh air supply inlet is located upstream of the water coil.
The 125 mm collar which houses the flow controller is made
of ABS.
The 60 m
3
/h or 16.6 l/s fresh air controller may be modified on
site by relocating or removing two plastic restricters in order
to increase its constant fresh air flow capacity to a maximum
of 160 m
3
/h or 44.4 l/s.
A label on the ICM shows how to readjust the two plastic
restricters.
Modification procedure
• Disconnect the fresh air duct from the plastic spigot on the
ICM.
• Remove the fresh air controller from inside the spigot.
• Move or relocate the two plastic restricters.
• Replace the fresh air controller in the spigot.
• Reconnect the fresh air duct to the spigot.
NOTE:
Two types of plastic spigot may be fitted to the ICM, depending
on the capacity of the fresh air controller chosen. One spigot
can accept only the 8.3 l/s or 30 m
3
/h controller. The other one
can accept only the field modifiable 16.6 l/s or 60 m
3
/h
controller. This means there is no possibility of mixing up the
two types of controller during installation or servicing.
IMPORTANT:
If the ICM is fitted with a return air temperature sensor, the
constant fresh air flow rate must not exceed 50% of the air
flow rate delivered by the unit at minimum speed.
NOTE:
To operate correctly, the 8.3 l/s or 30 m
3
/h constant fresh air
flow controller requires a differential pressure in the range
50 Pa to 200 Pa. The 16.6 l/s or 60 m
3
/h constant fresh air
controller requires a differential pressure in the range 70 Pa
to 200 Pa.
5.2 - Fresh air duct as optional accessory
Flexible fresh air duct, diameter 125 mm, maximum length
0.5 m, fitted with two coupling sleeves integral with the duct
(the duct fire rating is M1).
FRESH AIR CONTROLLER
