2
Maintenance
FläktGroup
DC_9202GB 20180403_R0
Specifications are subject to alteration without notice
Fig. 1
STORAGE BEFORE INSTALLATION
The storage area must not be exposed to vibrations from the
surroundings of a kind which can give bearing damage. If the storage
period exceeds 3 months, the belt drive tension should be released
and the fans should be rotated by hand at regular intervals.
BEFORE STARTING
Do not start the fan if any damper on the inlet or dis charge side are
closed. The LQLF fan (with forward-curved blades) must not be run
if it is not connected to the ducting, and the inspection door must be
closed to avoid tripping of the motor protection. However, the motor
may be briefly energized with the inspection door open for checking
the direction of rotation.
Before starting the fan, check that the impeller rotates freely and that
no objects which may be drawn in and damage the fan have been left
inside the unit.
When commissioning a new unit, check the belt tension and adjust, if
necessary, after 30 min. of operation (see below).
If the fan is equipped with steel spring anti-vibration mountings, the
transport safety brackets must be removed prior to start.
MAINTENANCE
The fan should be inspected and cleaned every 12 months. The
intervals between service are based on the assumption that the unit
is in operation for about 2000 hours per 12-month period in a normal
comfort installation. If the supply and/or exhaust air has a high dust
content, the unit should be serviced more frequently.
Check the belt tension every 6 months. The fan is accessible through
the inspection door/panel.
IMPORTANT!
Isolate the power supply and wait until the
impeller has stopped rotating (approx. 1 minute)
before inspecting and servicing the fan. There may
be designs of duct systems that causes wind
milling which prevents the impeller from being
stopped. The wind milling must then be prevented;
1) turn off the power to the fan
2) close the dampers.
CLEANING
Wipe the fan with a cloth. It is particularly important to keep the
impeller clean to avoid unbalance and vibration.
Caution!
Do not use liquids, since these may seep in between the
sheet-steel joints and will be absorbed by the casing insulation (does
not apply to casing type LQWA).
BELTDRIVE LQLR AND LQLS
TO ADJUST THE BELT TENSION
The belts must be correctly tensioned to ensure good contact with the
pulleys. If insufficiently tensioned, the belts may slip, and if excessively
tensioned, the motor and fan bearings may be overloaded.
When correctly tensioned, the belt deflection L will be 15 mm per
metre of distance between centres (c/c) when a force P (N) is applied.
The deflection and force should preferably be measured by means of a
tensiometer, see Fig. 4 and 5. The force P is dependent on the belt type
as shown in the table below.
The belts should be rechecked after about 30 minutes of operation.
Belt
section
Effective diameter of smaller
pulley, mm<
P in N/belt
Normal
Max.
1)
SPZ
67–95
10
15
SPZ
100
≤
15
20
SPA
90-132
20
27
SPA
140
≤
28
35
SPB
160-224
35
50
SPB
236
≤
50
65
SPC
224-355
60
90
SPC
375
≤
90
120
1)
Newly fitted belts.
Fig. 2
L
c/c
P
EUL(B,F) 10
