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Operation and Maintenance Instructions
Envistar Top 04-21
DSET.181201.00.EN
Continuous product development may give rise to specification changes without notice.
6.8 Fan unit (code ELFF)
The purpose of the fans is to transport air through the system, i.e. the fan must
overcome the flow resistance in air terminals, air ducts and the unit.
The fan speed is regulated to provide correct air flow. If the fans generate a low-
er air flow, this will impair the function of the ventilation system.
•
If the supply air flow is too low, the system will be out of balance, causing
poor room climate.
•
If the extract air flow is too low, the ventilation capacity will be unsatisfactory.
Imbalance may also force moist air out into the building structure.
One reason why the fans are generating too little air flow may be that impuri-
ties have collected on the fan impeller blades.
WARNING!
High voltage, risk of personal injury.
Working on/servicing the unit
–
Shut down the unit via the ser-
vice switch in the control equipment, then turn the safety switch
to the 0 position and lock it.
WARNING!
Rotating fan impeller, risk of personal injury. Shut down the unit
via the service switch in the control equipment, then turn the
safety switch to the 0 position and lock it. Wait at least 3 min-
utes before opening inspection doors.
1. EC motor with control unit
2. Fan impeller
3. Anti-vibration mounting
3
1
2
3
1
2
Fan unit, sizes 04 and 06
Fan unit size
10-21
