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Maintenance
Direct expansion coils
Never use hot water or steam to clean these coils. During
normal operation, the fin block must not ice up. If this occurs,
check the refrigeration system.
Refrigerant coils should be kept clean to maintain maximum
performance. If fins become dirty, clean with cold water and
detergent or one of the commercially available chemicals coil
cleaners. Rinse coils thoroughly after cleaning.
Never use steam or hot water to clean a refrigerant coil.
Dangerous pressures may be built up by improper
application of heat resulting in equipment damage or
personal injury.
7. Coil Winterization
Provisions must be made to drain those coils that are not in
use when subjected to freezing temperature.
Failure to properly drain and vent coils when not in use
during freezing temperatures may result in coil
freeze-up damage. Drain and vent hardware provided
by installing contractor.
To drain these coils, blow out the coils with compressed air, fill
and drain the tubes with full-strength ethylene glycol several
times, and then drain the coil as completely as possible.
8. Pulley and Belt
Proper installation techniques will assure that you get full
service life and minimum down time from your belt drives.
1.
Turn machine OFF and lock out power source.
2.
Remove belt guard, loosen motor mounts and shorten
center distance between pulleys. Remove old belts.
3.
lnspect Repair or replace drives components.
•
Clean oil, grease and debris from pulleys, remove rust
with wire brush.
•
Inspect and replace damage pulleys. Get your
money's worth from a new set of belts by checking and
replacing worn or damaged pulleys. In the long run,
replacement pulley cost will more than be covered in
increased belt life, reduced downtime, and lower
maintenance expenses.
WARNING
CAUTIONS
Check following:
a)
Worn groove sidewalls, "Dishing" should not exceed
1/32"(0.8mm) for individual belts. With a banded belt,
dishing should not exceed 1/ 64"(0.4mm). When a banded
belt rides too low in worn pulley grooves the tie band can
be cut by the flanges between the grooves.
b)
Shiny pulley groove bottoms. This is a sure sign that the
belt has bottomed out. The resulting slippage shorten belt
life.
c)
Wobbling and/or damaged pulleys. Generally caused by
improper pulley or bushing installation, wobbling and/or
damaged pulleys can unbalance a drive, wear out belt
rapidly, and damage bearings and bend shafts. Check and
repair worn bearings and bent shafts.
4.
Select replacement belts. Replace all belts on a drive with
a new matched set.
a)
Do not mix old and new belts on a drive. A new belt will ride
higher in the pulley groove and operate at a higher tension
than an old belt. Running them together will damaged the
new belt as it cannot carry its share of the load.
b)
Do not mix belt from different make, because dimensions
and constructions will vary running such "Mis-Matched"
belts will not give full service life.
c)
Replace with correct type and cross section belt. Matched
SPA section belt with SPA section pulleys. Do not put a
SPA belt section on a SPB section pulley. Also
dimensionally similar belts can have very different
horsepower rating.
5.
Install new belts
•
Loosen the drive take up and place the new belts on
the pulley. Press the belts with your hand to position
the slack of each belt on the same side of the drive. lf
the slack is on different sides. start-up loads can break
belt tensile cords.
•
Do not pry or force belts onto the pulleys. This can
break the load carrying tensile cords of the belt and the
belts will break or turn over shortly after installation.
•
Take up sleck until belts if snugly.
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