Lennox ROOFTOP FLEXY FXK 100, Installation, Operating And Maintenance

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IOM – FLEXY II – 1007 – E Page 33
BELT TENSION
On deliv ery, the driv e belts are new and correctly
tensioned. After the first 50 operating hours check and
adjust the tension. 80% of the total elongation of belts is
generally produced during the first 15 hours of operation.
Bef ore adjusting the tension, make sure that the pulleys
are correctly aligned.
To tension the belt, set the height of motor support plate
by moving the plate adjustment screws.
The recommended def lection is 20 mm per meter from
centre to centre.
Check that according to the diagram below (f igure 12), the
f ollowing ratio remains the same.
The belts should alway s be replaced when:
- The disk is set to maximum,
- The belt rubber is worn or the wire is visible.
Replacement belts must hav e the same rated size as the
ones they are replacing. If a transmission system has
sev eral belts, they must all be f rom the same
NOTE:
An under-tensioned belt will slip, heat and wear
prematurely. On the other hand, if a belt is over-tensioned,
the pressure on the bearings will cause them to over-heat
and wear prematurely. Incorrect alignment will also cause
the belts to wear prematurely.
VENTILATION : BELT TENSION
Fig. 12