Page 49
Operation and Maintenance
Envistar Top 04-21
DSET.190501.01.EN
Continuous product development may give rise to specification changes without notice.
Inspection
1. Remove one end of the fan assembly’s earth braid. If necessary, split the
motor cable's quick connector.
For size 04-06
: Remove the screws (position 1) in the connection plate
(position 2) and unhook the fan unit from the key holes in the anti-vibration
supports (position 5 and 6), both upper and lower.
For size 09-21
: Remove the screws (position 1) and the pins (position 2).
Remove the side cover (pos 6). Pull out the fan units (fan and motor are
mounted on slide rails).
2. Check that the fan impeller rotates easily, is in balance and does not vibrate.
Also check that the fan impeller is clean from any accumulation of particles.
Imbalance may be due to a coating or damage to the fan impeller blades.
3. Listen to the sound from the motor bearings. If the bearings are in good
condition, you will hear a slight purring sound. A scraping or pounding sound
may mean that the bearings are damaged and service is then required.
4.
For size 04-06
: Check that the fan impeller with motor (position 7) is firmly
mounted in the upper fan support (position 9) and that it has not shifted
sideways toward the inlet cone (position 3). Also check to make sure that the
inlet cone is properly secured. Check that the anti-vibration mountings (posi-
tion 4) are intact and are firmly fitted.
5.
For size 09-21
: Fan impeller (pos 5) and motor (pos 4) are mounted on a
frame equipped with anti-vibration mountings. Check that the anti-vibration
mountings (position 3) are intact and are firmly fitted.
1
1
3
5
9
7
6 4
2
8
8
4
1
1
3
4
5
6
2
Example fan unit size 04-06
Example fan unit size 09-21
1. Screws suspension
2. Connection plate
3. Inlet cone
4. Anti-vibration mounting
5. Anti-vibration support lower
6. Anti-vibration support upper
7. Fan impeller with motor
8. Edge cover
9. Fan support, upper
1. Screws side cover
2. Pins
3. Anti-vibration mounting
4. Motor
5. Fan impeller
6. Side cover
